Alysha Roberts, elective student
Alysha Roberts, elective student
Patrick Gallagher, MED III
MUN Class of 2022
Reviewed by Dr. Robin Clouston
Copyedited by Dr. Mandy Peach
Case
A 53-year-old female presents to the emergency department with a two-day history of left-eye pain, which she describes as “something being stuck in her eye.” The patient endorses left eye tearing, pruritis, and photophobia. She notes that her eye has been “blurry” since she awoke this morning. The patient denies any infectious symptoms at present but states that a cold sore erupted on her upper lip seven days ago. She does not use contact lenses.
Past medical history: T2DM and hypothyroidism.
Past surgical history: None.
Medications: Metformin 500 mg OD and Synthroid 125 mcg OD.
Physical exam:
Upon inspection, the patient has conjunctival injection and tearing in the left eye. Mild periorbital edema and erythema is noted. The patient’s pupils are equal and reactive to light, and visual acuity is 20/20 in the left eye and 20/40 on the left eye. Extraocular eye movements and visual fields are normal. The patient has decreased corneal sensation.
On slit lamp examination using fluorescein-based dye, a small branching dendritic ulcer was seen (Figure 1).
Figure 1: Dendritic ulcer noted on slit-lamp exam with fluorescein-based dye.
What is the differential diagnosis of dendrites?
• Herpes simplex keratitis
• Acanthamoeba keratitis
• Other keratitis caused by Varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein–Barr virus (EBV), or adenovirus.
• Dendritiform keratopathy
• Ramous epithelial changes
• Limbal stem cell deficiency
• Drug induced corneal changes (epinephrine, antivirals, beta-blockers) 1,2
Herpes simplex is a DNA virus that can cause a wide variety of infections, most commonly involving the mouth, genitalia, and eyes3. While HSV-1 and HSV-2 can involve the eye, HSV-1 is the most common cause of keratitis1. Herpes simplex keratitis (HSK) is characterized by recurrent infections of the corneal epithelium and stroma2. HSK can be classified as primary or recurrent and further divided into three subtypes: epithelial, stromal, and endothelial3. Epithelial keratitis is the most commons subtype of ocular herpes (50% to 80%)2.
Herpes simplex virus (HSV) infections are the leading cause of infectious corneal blindness in developed countries3. It is estimated that 1.5 million people worldwide experience HSV keratitis every year2.
Pathophysiology:
Primary HSV eye infections occur when the virus enters mucous membranes by direct contact. This initial infection is usually subclinical, but it can cause unilateral blepharitis, follicular conjunctivitis, and occasional epithelial keratitis (Figure 2)4. The initial infection is typically asymptomatic, and it occurs in children less than five years old5.
Figure 2: Pictorial representation of blepharitis (inflammation of the eyelid), keratitis (inflammation of cornea), conjunctivitis (inflammation of conjunctiva), and ocular anatomy. Diagram retrieved from 7
After the initial infection, the virus can remain latent in the ophthalmic division of the trigeminal ganglion for the lifetime of the host. HSV reactivation in the latently infected ganglia can lead to corneal scarring, thinning, stromal opacity, and neovascularization5. The cumulative effect of numerous infections results in vision loss and eventually blindness if left untreated.
History and physical:
Diagnosis of HSK is primarily diagnosed by clinical presentation on slit lamp exam using fluorescein and either rose bengal or lissamine green3. However, it is crucial to complete a thorough history and physical exam to narrow the differential diagnosis (Table 1).
Table 1: Key points on history and physical
Figure 3: Slit-lamp corneal findings for patient’s diagnosed with HSV epithelial keratitis. A: Classic dendritic lesion with terminal bulbs. B: More advanced dendritic lesion presenting as geographic ulcer. Figure modified from 6.
Investigations:
The diagnosis of HSVK is based off of clinical findings and does not require additional investigations; however, for atypical lesions, polymerase chain reaction has been used to confirm HSVK. Enzyme-linked immunosorbent assay and viral cultures are also effective in the diagnosis of the HSVK subgroups3.
Treatment/management of HSVK in the emergency department:
In the emergency department, typical findings on the slit lamp exam is diagnostic for epithelial HSVK.
Care providers should initiate treatment immediately to reduce the risk of complications; however, the patient must be referred to ophthalmology within the next few days for follow-up.
Topical and oral antiviral treatments effectively treat epithelial HSVK, although no topical ophthalmic antivirals are currently available in Canada7. It is crucial to adjust the dose of oral antivirals according to the patient’s renal function. See Table 2 for available oral antiviral treatments. For symptomatic management, artificial tears or eye lubricants can ease eye discomfort and over-the-counter analgesics can help relieve pain7.
Table 2: Oral antiviral treatment for epithelial HSVK in adults. Modified from 7
Back to the case:
Given our patient’s classic symptoms of epithelial HSVK (conjunctival injection, tearing, vision changes, foreign body sensation, photophobia, hx of HSV infection) and finding of dendritic ulcers on slit lamp examination, we treated this case as epithelial HSVK until proven otherwise. Therefore, we prescribed the patient valacyclovir 1000mg PO TID and arranged an urgent ophthalmology consult for the following day.
References:
Wilhelmus, K. R. (2015). Antiviral treatment and other therapeutic interventions for herpes simplex virus epithelial keratitis. Cochrane Database of Systematic Reviews, 1.
Azher, T. N., Yin, X. T., Tajfirouz, D., Huang, A. J., & Stuart, P. M. (2017). Herpes simplex keratitis: challenges in diagnosis and clinical management. Clinical Ophthalmology, 11:185–191.
Sibley, D., & Larkin, D. F. (2020). Update on Herpes simplex keratitis management. Eye, 34: 2219–2226.
Scott Clarke
Med III, Class of 2022
Dalhousie Medical School New Brunswick (DMNB)
Reviewed by Dr. Fraser MacKay
Copyedited by Dr. Mandy Peach
Case:
You are a clinical clerk working your first shift in a busy emergency department when you hear overhead those heart stopping, adrenaline pumping words: “Trauma team activation, room 24”. You arrive to find an unconscious 45 year old male. Report from the paramedics tells you there was a workplace accident whereby a tree had fallen and struck the patient in the face. The team works swiftly and efficiently to secure an airway and stabilize his vitals. From the team leader, your role is to perform a brief neurological exam.
Despite heavy sedation and swelling in the face, you are able to identify significant proptosis of his left eye. His right pupil is reactive to light but you notice his left responds significantly less and there is a positive relative afferent pupillary defect (RAPD). You relay your findings to the team lead and suggest an urgent CT scan of the head.
Before departing for CT your attending asks you – what diagnosis are you concerned for? What clinical findings support this diagnosis?
Orbital Compartment Syndrome1
Vision threatening condition where intraocular pressure (IOP) exceeds 40 mmHg.
Clues on exam:
Your attending agrees there is concern for orbital compartment syndrome and ophthalmology should be urgently paged – do you wait for CT to confirm retrobulbar hematoma?
No – You quickly grab a tono-pen and measure the intraocular pressure to be 50mmHg. In order to save this patient’s vision, a lateral canthotomy is immediately performed in an attempt to temporarily release pressure before definitive hematoma evacuation can occur.
Procedural Overview:
Equipment:
Anatomy review:
The globe of the eye is held firmly in place by the strong tarsal plates and the medial and lateral canthal ligaments (Figure 2). By dividing the lateral canthus (inferior limb or both inferior and superior limbs), the globe has room to expand which can greatly reduce pressure3.
Figure 2: Anatomy of the components holding the globe of the eye4.
Procedure5:
Once the procedure is completed you wait 5 minutes and reassess the intraocular pressure. You notice that it has gone from 50mmHg to 38mmHg. The patient is sent for CT head which confirms a retrobulbar hematoma.
You follow up with the patient during his hospital stay and discover his vision eventually returns to his normal pre-injury.
Keys to remember6:
Indications include trauma patients with:
– Proptosis
– Impaired ocular movements
– Elevated Intraocular pressure, usually >40mmHg
– Decreased visual acuity
– RAPD
Ideally performed within 60-120 min of features of ischemia to the optic nerve1.
Absolute contraindication:
– Globe rupture
Medical treatment can also be initiated with the goal to help decrease intraocular pressure 1:
See below for video of a lateral canthotomy on an actual patient (viewer discretion advised):
References
Nicholas Relja, B.Sc.(Hon), M.Sc.
Dalhousie Medicine New Brunswick
M.D. Candidate, Class of 2022
All case histories are illustrative and not based on any individual
Reviewed by Dr. Devon Webster
Copyedited by Dr. Mandy Peach
A 55-year-old male presented to the ED after concerned family brought him in due to ongoing generalized weakness lasting approximately one month. On inspection he had erythematous, scaly, ulcerative lesions covering his entire body with only facial sparing. He mentioned burning-like pain originating from his ulcerative lesions. He had been previously diagnosed with T-cell lymphoma 30 years ago and had gone through multiple rounds of chemo and radiation therapy since that time.
Picture from: Denis D, Beneton N, Laribi K, Maillard H (2019). Management of mycosis fungoides-type cutaneous T-cell lymphoma (MF-CTCL): focus on chlormethine gel. Cancer Management and Research. Vol 11: 2241-2251
Differential for itchy, erythematous rash:
Condition | |
Atopic dermatitis | |
Contact dermatitis | |
Drug eruptions | |
Erythrodermic psoriasis | |
Psoriasis | |
Sezary syndrome | |
Various lymphomas |
When reviewing the patient’s past medical history you see they were previously diagnosed with Mycosis Fungoides – a rare cutaneous form of T-cell lymphoma.
Mycosis fungoides has an incidence of approximately 6 cases per million per year in the United States. It is more common in adults over 50 years of age, with a male to female ratio of 2:1. The disease is also more common amongst the Black population than in Caucasians or Asians.8,9
The exact cause of mycosis fungoides is not known; however, there a variety of mechanisms that have been postulated:2
• Genetic and epigenetic abnormalities.3,4
• Environmental and occupational exposure to noxious substances and chemicals.5
• Human T-lymphotropic virus Type 1 – a suspected infection-type etiology.6
• Cytokines such as IL-2 and IL-4 due to their increased presence in patients with mycosis fungoides and Sezary syndrome.7
There are three stages of mycosis fungoides and therefore clinical presentation will vary depending on the stage of disease:
Patch stage: Erythematous, or brownish scaly patch, which may show some atrophy. It is possible to have one or multiple lesions develop in areas such as the gluteal region or on the proximal thighs. The likeness of this stage has been compared to “small-plaque” or “large plaque” parapsoriasis; however, the plaques are actually not plaques but patches instead.10
Plaque stage: This is the second stage – lesions will be larger, more numerous and will show infiltration. The lesions appear annular, are raised and have well-defined edges as well as asymmetry in terms of their distribution. Face and scalp involvement can also be seen starting at this stage.11
Tumor stage: The final stage – erythematous-purplish papules or nodules of larger diameter.12
There are other clinical variants of mycosis fungoides, but they are not as common, and some are quite rare.
Sezary syndrome:
In advanced form of the mycosis fungoides, Sezary syndrome may be present. This syndrome involves erythroderma with pruritus, lymphadenopathy and atypical circulating lymphocytes (referred to as Sezary or Lutzner cells).13
A detailed history and physical exam including checking for lymphadenopathy (most commonly cervical nodes) and organomegaly14,15 in addition to documenting the rash characteristics.
Labs: CBC, liver function tests, LDH
Radiological tests: depends on extent of lymphadenopathy and organomegaly. Can do a CXR in the ED for lung involvement, but otherwise advanced imaging can be decided upon by specialist consultant and may include CT, US, PET or MRI.
Biopsy: lymph nodes and rash – by consultants
Early stage:
Treatment options include topical therapies such as corticosteroids and other agents, UV therapy, local radiation and systemic immunosuppressants 15,16,17.
Advanced Stage:
Treatment for the advanced stages of mycosis fungoides are directed at disease control and symptom relief. Localized radiation, targeted immunotherapy or chemotherapy. 15, 18
The prognosis of mycosis fungoides is variable but in general as the stage gets more advanced and with patients over the age of 60, the prognosis becomes poorer. Other poor prognostic factors include increased LDH, tumor distribution and organ involvement.2
Case Conclusion
The patient seen in hospital by the dermatologist on call and was deemed to be in the plaque stage. He was admitted due to the advancing course and and inability to manage his symptoms from home. Further care will involve palliation and a focus on quality of life.
References:
Grace Dao, CC4
MD Candidate
Class of 2021
Mr. Payne Bach is a 54 yo male who presents to the emergency department via EMS with lower back pain.
He reports that he hurt his back this afternoon when he was picking up a heavy, antique chair. Immediately, he felt something “give out” in his back and reports a sharp 10/10 central lower back pain that radiates unilaterally to the left side. It did not radiate down his legs. He was unable to ambulate due to the pain and called EMS.
He received 975 mg Acetaminophen in the ambulance which did not alleviate his pain. Mr. Bach reports that before picking up the chair he was feeling well. He denies any history of back pain or activities of back overuse. He denies any history of trauma or injury to his back recently or in the past. In the emergency department he reports his pain remains at 10/10 and cannot sit up or move in bed due to the pain.
He denies any change in sensation or pain to his legs. He denies any change in sensation to his perineum or any bowel incontinence. He has not urinated since the incident. Incidentally when reviewing a past medical history he reports an unintentional weight loss of 15 lbs in the last 2 months. He denies any history of a prior cancer diagnosis. On review of systems he denies history of cough, fevers, night sweats, hematochezia or gross hematuria. Mr. Bach has a 20 pack year smoking history.
Mr. Bach had difficulty with the physical exam due to pain. He appeared very distressed. All vital signs were within normal limits. An order for IV opiods was ordered and he was reassessed 30 minutes later.
Physical exam
Inspection: there were no obvious deformities of the back, no scarring or bruising or abrasions. Mr. Bach continued to look uncomfortable but was no longer in any acute distress.
Palpation: Mr. Bach was tender to palpation over L4-5. There was tenderness to palpation of the paraspinal muscles at the same level.
ROM: Mr. Bach was very hesitant to move, thus, it was difficult to assess his range of motion.
Neuro: Reflexes at the knee and ankle were normal. Babinski was negative. Normal sensation throughout all dermatomes. 5/5 strength on flexion/extension at the hip, knee and ankle.
Special tests: Straight leg raise and Lasegue’s test were negative.
Back pain is an extremely common condition. It is estimated that 70-85% of people will experience back pain at some point in their life1. A recent study out of an emergency department in Halifax, found that 3.17% of patients presented with to the emergency department with a complaint of lower back pain2. Back pain is within the top 5 reasons for primary care visits3. The differential diagnosis for lower back pain ranges from mechanical lower back pain to critical conditions that need to be recognized 4. Due to its prevalence and potentially sinister causes it is important to have an evidence-based approach to lower back pain.
To Image or Not to Image-That is the Question
Choosing Wisely Canada has put out recommendations for both Family and Emergency physicians with regards to low back pain. For family medicine the recommendation is “don’t do imaging for lower-back pain unless red flags are present” 5. It has been found that imagining those without red flags before 6 weeks does not improve outcomes.5
Similarly, for emergency medicine the recommendation is “don’t order lumbosacral (low back) spinal imaging in patients with non-traumatic low back pain who have no red flags/pathologic indicators.”6
Red flags 6:
Cauda Equina Syndrome |
Severe worsening pain, especially at night |
Significant trauma |
Weight loss |
History of Cancer |
Fever |
Night sweats |
Steroid use |
IV drug use |
First episode of back pain in age > 50, especially concerning if age > 65 |
Widespread neurological signs (loss of sensation, loss of motor function, loss of reflexes in the legs) |
It is also important to remember that not all red flags are created equal and to include clinical judgement in the decision making process.8 A systematic review examining the predictive value of commonly assessed red flags found that for fracture older age, prolonged steroid use, severe trauma, and contusion/abrasion increased the probability of fracture to 10-33%, and if multiple red flags are present fracture risk increases to 42-90%.
When considering red flags that increase risk of malignancy, previous history of malignancy increased risk 7-33%; while older age, unexplained weight loss, and failure to improve after one month all were found to have post-test probabilities of less than 3% when predicting malignancy risk8.
Back to our case
Mr. Bach has red flags for both fracture and malignancy:
Severe, worsening pain |
Age > 50 |
Weight loss |
XRs of the lumbar spine were ordered and indicated several compression fractures, with one area suspicious for a metastatic lesion. Follow CT spine was ordered and confirmed metastatic disease. Mr. Bach was admitted to hospital for pain control, physiotherapy and a malignancy work up.
References
1. Andersson, G. B. (1999). Epidemiological features of chronic low-back pain. Lancet 354(9178):581-585. doi:10.1016/S0140-6736(99)01312-4
2. Edwards, J., Hayden, J., Asbridge, M., & Magee, K. (2018). The prevalence of low back pain in the emergency department: A descriptive study set in the Charles V. Keating Emergency and Trauma Centre, Halifax, Nova Scotia, Canada. BMC Musculoskeletal Disorders, 19(1), 306. https://doi.org/10.1186/s12891-018-2237-x
3. Finley, C. R., Chan, D. S., Garrison, S., Korownyk, C., Kolber, M. R., Campbell, S., Eurich, D. T., Lindblad, A. J., Vandermeer, B., & Allan, G. M. (2018). What are the most common conditions in primary care? Systematic review. Canadian family physician Medecin de famille canadien, 64(11), 832–840.
4. Patel, A.T., & Ogle, A.A. (2000). Diagnosis and management of acute low back pain. Am Fam Physician 61(6):1779-1790.
5. College of Family Physicians of Canada. Choosing Wisely Canada. Thirteen Things Physicians and Patients should question. July, 2019. Retrieved from: https://choosingwiselycanada.org/family-medicine/
6. Canadian Association of Emergency Physicians. Choosing Wisely Canada. Ten things Physicians and Patients Should Question. July, 2019. Retreived from: https://choosingwiselycanada.org/emergency-medicine/
7. Toward Optimized Practice (TOP). (2011). Guideline for the evidence-informed primary care Management of Low Back Pain. Retrieved from: https://portal.cfpc.ca/resourcesdocs/uploadedFiles/Directories/Committees_List/Low_Back_Pain_Guidelines_Oct19.pdf
8. Downie, A., Williams, C. M., Henschke, N., Hancock, M. J., Ostelo, R. W. J. G., de Vet, H. C. W., Macaskill, P., Irwig, L., van Tulder, M. W., Koes, B. W., & Maher, C. G. (2013). Red flags to screen for malignancy and fracture in patients with low back pain: Systematic review. BMJ, 347.
Copyedited by Dr. Mandy Peach
Sophia Miao, CC4
MD Candidate, Class of 2021
Dalhousie University
Reviewed & Edited by Dr David Lewis (@e_med_doc)
All case histories are illustrative and not based on any individual.
A 33-year-old woman presents to the ED with pain and swelling over the third digit of her right hand. One week prior to this, she had shattered a jar and a small glass splinter lodged into her finger. This was promptly removed at home, and the puncture wound healed without intervention.
She presented to the emergency room 7 days later with new pain and swelling surrounding the initial puncture wound. There is no significant past medical history and most recent Td booster was given 2 years ago. On examination, there was some mild erythema, swelling, and tenderness on palpation of the lateral aspect of the middle phalanx of the right hand. She is otherwise well. You wonder about the possibility of a retained foreign body.
Foreign bodies in soft tissue are a common complaint in the emergency department, with open wounds comprising 5.7 million (or 4.5% of total) visits to the ED in 2010.[1] Foreign bodies were found in up to 15% of wounds.[2] If retained, complications of these include allergic reaction, inflammation, delayed wound healing, damage to adjacent tissue structures, neurovascular damage, tetanus, and infectious complications including cellulitis, necrotizing fasciitis, synovitis, and abscess formation.[3],[4] Proper detection, and subsequent removal, of retained foreign bodies is therefore essential to evaluate the wound and prevent associated complications.
Diagnosis of a retained FB requires a high index of suspicion. Clinical suspicion should be raised when there is a compelling history and physical exam. The latter may include signs of inflammation and/or infection, including warmth, swelling, erythema, tenderness, abscess formation, and discharging wound).[5],[6]
Conventional radiography is known to commonly miss radiolucent materials such as wood and plastic. It has been shown that plain radiographs have only a 7.4% sensitivity in the detection of wood foreign bodies.5 Remarkably, even glass – a radiopaque material – has been demonstrated to have been missed in up to 35% of x-ray film studies.[7] There is increasingly compelling evidence for the clinical usefulness and accuracy of bedside ultrasonography in the detection of soft-tissue foreign bodies. It has been shown to have a specificity of 92% (95% CI = 88%-95%) and sensitivity ranging from 83.3% to 100%.[8],[9]
Probe selection: the use of a high-frequency ultrasound probe is recommended. This allows for greater axial resolution at the expense of less penetration, which is suitable for the detection of small foreign bodies, as they typically lodge in superficial tissues.[10]
If the wound is open, a transparent covering such as a Tegaderm or probe cover can be used to cover either the wound or probe before scanning.[11]
Medium: standard technique for assessment of soft-tissue structures by ultrasound involves the use of a standoff pad or gel mound. However, this is not always possible due to the irregular curvature of extremities such as fingers and feet, which may result in poor contact between the probe and skin, decreased field of view, and patient discomfort. A water-bath technique can circumvent this and has been shown to be superior in such cases.[12]
Method: the area of interest should be scanned in both longitudinal and transverse planes. Foreign bodies are best detected when the transducer aligns with the longitudinal axis of the foreign body, and therefore revealing the span of the object.[13] As foreign bodies tend to embed less than 2 cm below the surface of the skin, the depth of field should remain superficial in order to avoid false positives.
US Probe: Ultrasound Water Bath for Distal Extremity Evaluation
Ultrasonography and plain film findings of foreign bodies in soft tissue are summarized in the table below.
Table 1. Ultrasound and x-ray findings of foreign bodies.6,[14],[15],[16]
Material | Ultrasound findings | X-ray findings |
Wood | Hyperechoic; may become isoechoic with surrounding tissue as it denatures over time
Posterior acoustic shadowing |
Radiolucent, often undetectable |
Glass | Hyperechoic, bright
Posterior acoustic shadowing ± Posterior comet tail reverberation, diffuse beam scattering |
Radiopaque |
Plastic | Hyperechoic
Posterior acoustic shadowing |
Radiolucent, often undetectable |
Metal | Hyperechoic, bright
Posterior acoustic shadowing ± Posterior comet tail reverberation |
Radiopaque |
Foreign bodies may also display a straight or regular contour.6
Image 1 – Wood splinter in volar aspect digit, mildly hyperechoic, surrounding hypoechoic halo, irregular acoustic shadowing
Image 2 – Plastic FB, within tendon sheath, volar aspect digit, brightly hyperechoic, long axis
Image 3 – Plastic FB, within tendon sheath, volar aspect digit, brightly hyperechoic, short axis
Image 4 – Glass FB – brightly echogenic, posterior reverberation, FB long axis
Image 5 – Metal FB – brightly echogenic, posterior reverberation, FB long axis
It is important to note that the acoustic shadowing may be complete or partial, as this is dependent on the angle of sonography and foreign body material.[17] It is also possible to see a hypoechoic halo around the FB, which may be suggest edema, abscess formation, granulation tissue, or other inflammatory process.[18] As the inflammatory reaction develops, the halo effect becomes more apparent; therefore the foreign body is therefore best visualized by PoCUS several days after the initial injury.6
There are several options for removal of a foreign body with PoCUS:[19]
There is a risk of obscuring the view of the foreign body on ultrasound with air as a result of the incision itself or through anesthetic delivery. Saline may be used to irrigate and therefore mitigate the issue.19
The patient’s tetanus status should be verified and updated, if required. Antibiotic therapy may also be provided, should the risk of infection justify it.
There is the possibility of false positives. Foreign bodies must be differentiated from other hyperechoic body structures, including ossified cartilage, sesamoid bones, scar tissue, gas bubbles, and intermuscular fascia.14 Visualization is therefore important in both longitudinal and transverse planes, as well as comparison with the opposite side. Acoustic shadowing, hypoechoic halo, and posterior comet tails, if present, can also be indicative of a FB rather than organic body tissue.
Traumatic air injection as a result of penetrating injury can create a scatter artifact on ultrasound, which can be misinterpreted as an acoustic shadow associated with a foreign body. To differentiate this from a true acoustic shadow, pressure may be applied through the transducer to displace the scatter artifact.6
As is commonplace with all emergency ultrasonography, limitations also include the technical skill of the operator.[20] A foreign body may also be too small to be detectable by ultrasound. It is therefore important to remember that a negative scan does not necessarily rule out the possibility of a retained foreign body, and the history and physical examination must be considered in conjunction with the ultrasound findings.
[1] National Center for Health Statistics. Emergency Department Visits. Available from: http://www.cdc.gov/nchs/fastats/emergency-department.htm.
[2] Steele MT, Tran LV, Watson WA, Muelleman RL. Retained glass foreign bodies in wounds: predictive value of wound characteristics, patient perception, and wound exploration. Am J Emerg Med. 1998 Nov;16(7):627-30. DOI: 10.1016/s0735-6757(98)90161-9. PMID: 9827733.
[3] Skinner EJ, Morrison CA. Wound Foreign Body Removal. In:StatPearls. Treasure Island (FL): StatPearls Publishing; 2020. Available from: https://www.ncbi.nlm.nih.gov/books/NBK554447/.
[4] Ebrahimi A, Radmanesh M, Rabiei S, Kavoussi H. Surgical removal of neglected soft tissue foreign bodies by needle-guided technique. Iran J Otorhinolaryngol. 2013 Winter;25(70):29-36. PMID: 24303416; PMCID: PMC3846242.
[5] Levine MR, Gorman SM, Young CF, Courtney DM. Clinical characteristics and management of wound foreign bodies in the ED. Am J Emerg Med. 2008 Oct;26(8):918-22. DOI: 10.1016/j.ajem.2007.11.026. PMID: 18926353.
[6] Atkinson P, Bowra J, Harris T, Jarman B, Lewis D. Point of Care Ultrasound for Emergency Medicine and Resuscitation. Oxford, United Kingdom: Oxford University Press; 2019. DOI: 10.1093/med/9780198777540.001.0001.
[7] Kaiser, C. William MD; Slowick, Timothy MBA; Spurling, Kathleen Pfeifer RN, JD; Friedman, Sissie MA. Retained Foreign Bodies, The Journal of Trauma: Injury, Infection, and Critical Care: July 1997 – Volume 43 – Issue 1 – p 107-111.
[8] Davis J, Czerniski B, Au A, Adhikari S, Farrell I, Fields JM. Diagnostic Accuracy of Ultrasonography in Retained Soft Tissue Foreign Bodies: A Systematic Review and Meta-analysis. Acad Emerg Med. 2015 Jul;22(7):777-87. DOI: 10.1111/acem.12714. Epub 2015 Jun 25. PMID: 26111545.
[9] Atkinson P, Madan R, Kendall R, Fraser J, Lewis D. Detection of soft tissue foreign bodies by nurse practitioner-performed ultrasound. Crit Ultrasound J. 2014 Jan 29;6(1):2. DOI: 10.1186/2036-7902-6-2. PMID: 24476553; PMCID: PMC3922659.
[10] Dean AJ, Gronczewski CA, Costantino TG. Technique for emergency medicine bedside ultrasound identification of a radiolucent foreign body. The Journal of Emergency Medicine. 2003;24(3):303–8. DOI: 10.1016/S0736-4679(02)00765-5.
[11] Chen KC, Lin AC, Chong CF, Wang TL. An overview of point-of-care ultrasound for soft tissue and musculoskeletal applications in the emergency department. J Intensive Care. 2016 Aug 15;4:55. DOI: 10.1186/s40560-016-0173-0. PMID: 27529031; PMCID: PMC4983782.
[12] Krishnamurthy R, Yoo JH, Thapa M, Callahan MJ. Water-bath method for sonographic evaluation of superficial structures of the extremities in children. Pediatr Radiol. 2013 Mar;43 Suppl 1:S41-7. DOI: 10.1007/s00247-012-2592-y. Epub 2013 Mar 12. PMID: 23478918.
[13] Rooks VJ, Shiels WE 3rd, Murakami JW. Soft tissue foreign bodies: A training manual for sonographic diagnosis and guided removal. J Clin Ultrasound. 2020 Jul;48(6):330-336. DOI: 10.1002/jcu.22856. Epub 2020 May 8. PMID: 32385865.
[14] Mohammadi A, Ghasemi-Rad M, Khodabakhsh M. Non-opaque soft tissue foreign body: sonographic findings. BMC Med Imaging. 2011 Apr 10;11:9. DOI: 10.1186/1471-2342-11-9. PMID: 21477360; PMCID: PMC3079678.
[15] Lewis D, Jivraj A, Atkinson P, Jarman R. My patient is injured: identifying foreign bodies with ultrasound. Ultrasound. 2015 Aug;23(3):174-80. DOI: 10.1177/1742271X15579950. Epub 2015 Mar 26. PMID: 27433254; PMCID: PMC4760591.
[16] Campbell EA, Wilbert CD. Foreign Body Imaging. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020. Available from: https://www.ncbi.nlm.nih.gov/books/NBK470294/.
[17] Anderson MA, Newmeyer WL 3rd, Kilgore ES Jr. Diagnosis and treatment of retained foreign bodies in the hand. Am J Surg. 1982 Jul;144(1):63-7. DOI: 10.1016/0002-9610(82)90603-1. PMID: 7091533.
[18] Little CM, Parker MG, Callowich MC, Sartori JC. The ultrasonic detection of soft tissue foreign bodies. Invest Radiol. 1986 Mar;21(3):275-7. DOI: 10.1097/00004424-198603000-00014. PMID: 3514541.
[19] Paziana K, Fields JM, Rotte M, Au A, Ku B. Soft tissue foreign body removal technique using portable ultrasonography. Wilderness Environ Med. 2012 Dec;23(4):343-8. DOI: 10.1016/j.wem.2012.04.006. Epub 2012 Jul 25. PMID: 22835803.
[20] Pinto A, Pinto F, Faggian A, Rubini G, Caranci F, Macarini L, Genovese EA, Brunese L. Sources of error in emergency ultrasonography. Crit Ultrasound J. 2013 Jul 15;5 Suppl 1(Suppl 1):S1. DOI: 10.1186/2036-7902-5-S1-S1. Epub 2013 Jul 15. PMID: 23902656; PMCID: PMC3711733.
Alysha Roberts
MD Candidate, Class of 2021
Dalhousie University
Reviewed & Edited by Dr David Lewis (@e_med_doc)
All case histories are illustrative and not based on any individual.
A 40 year old male presents to the emergency department with a red, swollen eye. Without a known trigger, he had a one day history of progressive pain, erythema, and edema surrounding his left eye. He denied any fever or chills or visual changes, or headache. A thorough review of systems was negative, except for a complaint of worsening pain with extraocular movement.
On exam, he was afebrile and his vital signs were within normal limits. His visual acuity was normal, and pupils were equal and reactive to light. Extraocular movements were intact but associated with worsening pain. The periorbital tissue was erythematous, edematous, and hot to touch. Examination is limited by the severity of the patient’s swelling. Figure 1 illustrates an example of a patient with severe, unilateral eyelid swelling and erythema.
You suspect periorbital cellulitis.
Figure 1. Unilateral eyelid edema. Retrieved from https://www.merckmanuals.com/professional/eye-disorders/orbital-diseases/preseptal-and-orbital-cellulitis
Periorbital cellulitis, commonly referred to as pre-septal cellulitis, is an infection of the skin and soft tissue surrounding the orbit. Most commonly, it is the result of an infection spreading from the sinuses or from local trauma.1,2 It presents as a unilateral swelling of the eye-lid. Both periorbital and orbital cellulitis are most commonly caused by Staphylococcus Aureus and Streptococcus Pneumoniae. It is important to distinguish periorbital from orbital cellulitis, which is an infection of the orbit itself extending beyond the orbital septum. Orbital cellulitis is a sight-threatening emergency, and urgent imaging should be acquired in addition to consultation with ophthalmology or otolaryngology.3 Other complications of orbital cellulitis include orbital or subperiosteal abscess, and cavernous sinus thrombosis. Figure 2 illustrates the difference between periorbital (preseptal) and orbital cellulitis, as well as its complications.
Figure 2. Orbital anatomy and potential complications from orbital cellulitis. Retrieved from https://www.merckmanuals.com/professional/eye-disorders/orbital-diseases/preseptal-and-orbital-cellulitis
Any patient with unilateral eyelid edema should be evaluated for red flags of orbital cellulitis, given its potential seriousness. Red flag signs and symptoms include:3,4
Other considerations for the differential diagnosis in a unilateral, swollen red eye include:5
Risk factors for periorbital and orbital cellulitis include:6
Periorbital cellulitis is most commonly caused by an insect bite in children, and trauma in adults. Comparatively, orbital cellulitis is most often the result of trauma in children, and sinusitis in adults.
Patients who are febrile or appear unwell should have early initiation of IV antibiotics following blood cultures. Though periorbital cellulitis is a clinical diagnosis, if there is suspicion for orbital cellulitis a CT scan of the orbits and sinuses is the gold standard. Positive findings include inflammation of extraocular muscles, anterior globe displacement, and fat stranding. Inflammation of the sinuses should not be used to differentiate periorbital from orbital cellulitis, as up to 41% of cases of periorbital cellulitis may have CT evidence of sinusitis. Figure 3 displays a labelled CT image with common findings in orbital cellulitis.7
Figure 3. Orbital CT image with labels. Retrieved from https://ctscanmachines.blogspot.com/2018/07/ct-scan-of-periorbital-cellulitis.html
In addition to CT imaging, there may be a role for point of care ultrasound (PoCUS) in the diagnosis and management of periorbital and orbital cellulitis. However, research is currently lacking on whether its use may avoid the need for further diagnostic imaging.8 Findings from pediatric emergency medicine suggest that orbital ultrasound may be preferred in evaluating young patients who are unable to cooperate with a thorough physical examination.9 One important application of orbital PoCUS is in the assessment of orbital abscesses. Subperiosteal abscesses may complicate more than 50% of cases of orbital cellulitis, and are not reliably detected by CT.10 Additionally, orbital ultrasound may be an appropriate alternative in settings where advanced imaging is not available, in order to guide early initiation of antibiotics.
Orbital Abscess from – The PoCUS Atlas
Antibiotic choice should be guided by local susceptibility guidelines. An appropriate choice would cover S. aureus, S. pyogenes, and anaerobes.11,12 In this case, we initiated intravenous ceftriaxone and metronidazole while awaiting CT results.
The following therapeutic guidelines are from Bugs and Drugs – It is recommended that that guidelines for therapy are accessed directly from their website or from other reputable sources.
From Bug and Drugs
Given this patient’s complaint of increased pain with extraocular movement, a CT orbit was performed. Fortunately, there were no signs of orbital cellulitis. The patient was treated with IV ceftriaxone and metronidazole and scheduled to return to the emergency department the next day for re-evaluation and consideration of step-down to oral antibiotics.
Orbital cellulitis is a serious condition that should be carefully distinguished from periorbital cellulitis. On history, clinicians should ensure they inquire about recent sinus or dental infections, trauma to the orbit, or possible insect bites. Physical exam should carefully assess for signs of orbital cellulitis, including proptosis, chemosis, and limited extraocular movements. Any positive red flag or clinical suspicion warrants a CT scan of the orbits and sinuses to exclude orbital cellulitis.
Great photo article in Canadian Family Physician
Alana Jewell
M.D. Candidate, Class of 2022
Memorial University Faculty of Medicine
Reviewed & Edited by Dr. Mandy Peach
All case histories are illustrative and not based on any individual.
Case Presentation
A 70-year-old gentleman presented with four days of right upper abdominal pain radiating to the LUQ with nausea + vomiting, anorexia, flatulence, and bloating. Patient has PMHx of Crohn’s disease with a history of small bowel obstruction (SBO) and multiple surgeries. He felt these symptoms were like his SBO but he continued to have normal bowel movements. He had a similar episode a few months ago after eating fast food, but did not seek care for.
You suspect cholecystitis.
Differential Diagnosis
Can’t miss diagnoses for atraumatic abdominal pain 4:
ruptured AAA |
pancreatitis |
cholangitis |
mesenteric ischemia |
obstruction |
perforated viscus |
complicated diverticulitis |
ruptured ectopic pregnancy |
Differential for RUQ pain 4 :
hepatitis |
biliary colic |
cholecystitis |
cholangitis |
pancreatitis |
pneumonia |
pleural effusion |
pulmonary embolism |
There is no single exam finding or laboratory test that has the ability to rule out acute cholecystitis5.
A combination of clinical evaluation, laboratory values, and diagnostic imaging are key to differentiate abdominal pain and make a diagnosis.
Cholecystitis
Cholecystitis is defined as inflammation of the gallbladder, typically caused by persistent stone obstruction in the cystic duct.
Acute cholecystitis (AC): Stone obstruction leads to bile trapping, increased intraluminal pressure, and an acute inflammatory process, typically presenting with RUQ pain, leukocytosis, and fever1.
Chronic cholecystitis: defined as recurrence of these events and is associated with fibrosis and mucosal atrophy2.
Acalculous cholecystitis: consider in chronically debilitated patients, classically elderly patients in ICU on total parental nutrition after sustained trauma or significant burn injury11.
Ascending (or acute) cholangitis: an important complication of cholecystitis – a serious bacterial infection of the common bile duct. It presents with Charcot’s triad of fever, jaundice, and abdominal pain2.
Acute cholecystitis is diagnosed and graded on severity by using the Tokyo Guidelines3.
Gallstones (which cause 95% of acute cholecystitis) are common in Western society, with about 10% of people affected, and 80% of those affected being asymptomatic1,3. The risk of pain or complications is 1-4% per year2.
Risk factors for cholesterol gallstones (the most common type) 2:
increased age |
female gender |
pregnancy |
parity |
race |
high calorie |
low fibre diet |
low activity |
obesity |
Clinical Presentation and findings
Clinical presentation varies with severity.
On history, a patient may have anorexia, emesis, fever, nausea, and RUQ pain. On examination, guarding, Murphy’s sign (pain upon deep inspiration while palpating RUQ), rebound tenderness, abdominal rigidity, and RUQ tenderness may be seen2. Patients may describe a history of biliary colic, but with the presenting episode being more severe and longer in duration.
Mild-moderate cases have RUQ pain, fever, leukocytosis, and may have a palpable mass in the RUQ2. The most severe patients may have jaundice and, if have a secondary bacterial infection, could have signs of sepsis.
Case Continued
Physical Exam
Patient was tender to light palpation over RUQ and epigastric region. No rigidity, rebound tenderness, or guarding was noted.
Bloodwork
The most common laboratory findings in acute cholecystitis are an increased CRP and leukocytosis2.
This patient requires imaging to confirm the suspected diagnosis.
Diagnostic Imaging
Ultrasound
Ultrasound is the first-choice modality for imaging of AC. It is easily available in any emergency department, cost-effective, and minimally invasive3. Ultrasound findings can include5,6,9, as seen below 6.
GB wall thickening > 3.5 mm |
pericholecystic fluid |
biliary sludge |
gallstones |
sonographic Murphy sign |
If an ultrasound is positive, there is no need for further testing.
If negative, a CT should be ordered to exclude other diagnoses2,7.
CT findings for AC may include 3,6 as seen below 2:
thickening of GB wall |
enlargement of GB |
gallstones in GB neck or cystic duct |
fluid accumulation around GB |
pericholecystic fat stranding |
Many gallstones are not radiopaque and may be missed on CT7.
Management
Assessment with Tokyo Guideline diagnostic criteria can be used every 6-12 hours until a diagnosis is clear if initially uncertain, and to check severity until surgical management8.
In the Emergency Department, a patient is best managed with supportive care.
IV fluids, |
NPO |
Analgesia (NSAIDs are first-line treatment for AC. If ineffective, opioids are second line2. ) |
Secondary infection can result from bile stasis. Empiric antibiotics may be started against E. coli, Klebsiella, and Enterococcus5.
Definitive treatment for AC is cholecystectomy, with the gold standard being done laparoscopically (lap-C)2,7. Having a lap-C within 24-72 hours of symptom onset is recommended to decrease complication rates. If left unoperated for more than 72 hours chronic inflammation may occur, potentially complicating the surgery1. If a patient is ineligible for surgery, percutaneous cholecystostomy (gallbladder drainage) may be performed7.
Case Conclusion
Formal ultrasound found a hydropic gallbladder with pericholecystic fluid, thickened wall, and stranding. Cholecystitis was diagnosed. The patient was given analgesia and covered with ceftriaxone and metronidazole10. He went on to have an uncomplicated lap cholecystectomy.
References
MD Candidate, Class of 2021
Memorial University of Newfoundland
Reviewed and Edited by Dr. David Lewis
All case histories are illustrative and not based on any individual
A 36-year-old G2P1 female presented to the Emergency Department following a pre-syncopal episode at work. The patient noted a sudden onset of significant abdominal cramping, nausea, and vaginal bleeding with clots that morning followed by an episode of lightheadedness while sitting at her desk. The patient denied any loss of consciousness, no dyspnea, no chest pain, no palpitations, and no fevers/chills. She had no known allergies and no current medications. She was a non-smoker and denied any alcohol or drug usage.
The patient’s past medical history was significant for recent treatment with methotrexate for an ectopic pregnancy eight days prior. The patient had a history of amenorrhea for 7 weeks and a serum β-hCG of 302 mlU/mL at that time. A transvaginal ultrasound was performed at 8 weeks for abdominal pain and light spotting which revealed an IUD in situ with no evidence of an intrauterine pregnancy. An early ectopic pregnancy was diagnosed and the patient was consented to receive medical management with methotrexate. She was followed up with serial β-hCG’s which gradually, but slowly, trended down to 110 mIU/ml by day 6. The patient noted slight abdominal cramping and PV bleeding following the methotrexate however this had settled after 3 days with no ongoing symptoms until today.
On initial assessment, the patient appeared well, no acute distress, and all vital signs were stable. The abdominal exam revealed bowel sounds present in all four quadrants and the abdomen was tympanic to percussion. On palpation the abdomen was soft and nondistended with LLQ and suprapubic tenderness however, no guarding or rebound tenderness was appreciated.
Initial investigations included a CBC, β-hCG, PT & PTT, type and screen, urinalysis, EKG, & POCUS.
An ectopic pregnancy occurs when a fertilized egg implants at a site other then the endometrium of the uterus, most commonly the fallopian tubes. They often present as vaginal bleeding and/or abdominal pain in the setting of a positive β-hCG.1
A critical complication is a ruptured ectopic pregnancy which occurs by erosion through the tissue the zygote has implanted in resulting in intraabdominal bleeding from the exposed vessel and possible hypovolemic shock.2 Rupture should be suspected in patients presenting with hemodynamic instability including syncope, hypotension, and tachycardia. However, young healthy females may appear vitally stable initially due to compensatory mechanisms. Additional physical exam findings suggestive of a ruptured ectopic pregnancy include severe abdominal pain with guarding or rebound tenderness and abdominal distention. Pain may radiate to the shoulder due to irritation of the diaphragm from blood in the peritoneal cavity.1,3
According to the discriminatory zones, an intrauterine pregnancy is expected to be visualized on a transvaginal ultrasound at β-hCG levels of 1500 – 2000 mlU/mL and on a transabdominal ultrasound at levels of 4000 – 6500 mlU/mL.5
Gestational Age | Β-hCG range (mlU/mL) |
<1 week | 5 – 50 |
1-2 weeks | 50 – 500 |
2-3 weeks | 100 – 5000 |
3-4 weeks | 500 – 10,000 |
4-5 weeks | 1000 – 50,000 |
5-6 weeks | 10,000 – 100,000 |
6-8 weeks | 15,000 – 200,000 |
8-12 weeks | 10,000 – 100,000 |
Table 1: Estimated β-hCG levels in relation to gestational age.3
In the first trimester of a normal pregnancy, the serum β-hCG should increase by ≥ 53% every 48 hrs until 41 days of gestation.1,3 Serum β-hCG will then continue to rise more slowly until approximately 10 weeks after which it will begin to decline until reaching a plateau. Serum β-hCG levels are noted to raise more slowly in an ectopic pregnancy, thus a slower rate of increase, plateau, or decline in serum β-hCG in the first 41 days suggests a possible miscarriage or ectopic pregnancy.1
The value of discriminatory zones in the emergency management of ectopic pregnancy is low, with many considering it unreliable and potentially dangerous. In short, a low β-hCG does not exclude an ectopic. This useful post provides a good summary on ectopic rule-out in the ED:
An intrauterine pregnancy is confirmed by visualization of a gestational sac and a yolk sac within the uterus (juxtaposed to bladder).1 A gestational sac alone is not sufficient for diagnoses of an intrauterine pregnancy as it may be a pseudogestational sac formed by hormonal stimulation from an ectopic pregnancy.5 Additionally, if an intrauterine pregnancy is visualized, a heterotopic pregnancy should also be considered.1 The risk of heterotopic pregnancy when conceived normally is estimated to be 1 in 30,000.
Figure 1: Visualization of an intrauterine pregnancy on a transvaginal ultrasound.3
Structure | Transvaginal Ultrasound | Transabdominal Ultrasound |
Gestational Sac | 4.5-5 weeks | 5.5-6 weeks |
Yolk Sac | 5-5.5 weeks | 6-6.5 weeks |
Fetal Pole | 5.5-6 weeks | 7 weeks |
Cardiac Activity | 6 weeks | 7 weeks |
Fetal Parts | 8 weeks | >8 weeks |
Table 2: Ultrasound findings based on gestational age.5
An ectopic pregnancy is suspected in all women with a positive pregnancy test when no intrauterine pregnancy is visualized on ultrasonography. A low β-hCG or declining β-hCG does not exclude an ectopic. Ultrasound findings of an ectopic pregnancy may include an extrauterine gestational sac or embryonic cardiac activity outside of the uterus, a complex adnexal mass, or intraperitoneal fluid.3
The patient was hemodynamically stable on presentation. Her vital signs were normal. As part of the initial assessment, PoCUS was used to further evaluate for the presence of free fluid in the abdomen or pelvis. Free fluid was identified in the RUQ in both Morrison’s pouch and surrounding the caudal tip of the liver. Intraperitoneal fluid was also seen in the LUQ in both the subphrenic and splenorenal spaces. Free fluid was also visualized in Douglas’ pouch in the pelvic view.
RUQ
LUQ
Pelvis
Throughout the PoCUS examination the patient remained well appearing, however she had become hypotensive with a blood pressure of 90/53 mmHg. Her initial bloodwork had come back at this time revealing a β-hCG of 32 mlU/mL and a Hgb of 67 g/L. The patient received 1g of TXA, and a 1L bolus of normal saline while PRBC’s were ordered. She was documented to be Rh+ thus, she did not require RhoGAM (anti-D immune globulin). An urgent consultation to Obstetrics and Gynecology was made following the visualization of intraabdominal fluid and the patient underwent an exploratory laparotomy shortly after.
Ectopic Pregnancy and Ruptured Ectopic: Pitfalls in Diagnosis
Patrick Rogers, Clinical Clerk (CC3)
Memorial University of Medicine Class of 2021
Reviewed by Dr. Kavish Chandra
Small bowel obstructions (SBO) are a common cause of acute abdominal pain in emergency departments across Canada. Diagnostic imaging plays a key role in the diagnosis and management of SBO as the history, clinical examination and laboratory investigations lack the sensitivity and specificity needed. Furthermore, diagnostic imaging may help differentiate SBO from other causes of abdominal pain (hernias, malignancies, intussusception, etc).
Historically, plain film abdominal radiography (AXR) has been an initial investigation in emergency departments when an SBO is suspected. However, the current literature suggests that abdominal radiography is a relatively poor test for the diagnosis or exclusion of SBO when compared to other available modalities like US, CT, or MRI. In fact, multiple studies argue for the reduction of abdominal x-rays, especially when patients come in presenting with general abdominal tenderness. 1 Fortunately, there exists a compelling alternative: point of care ultrasound (PoCUS), and is being increasingly used as a first line investigation for SBO. 2
There are several reasons why physicians may start to choose PoCUS over traditional diagnostic modalities:
The current evidence is highly favorable for the diagnostic efficacy of PoCUS in SBO. Here are the findings of peer-reviewed studies on the subject (published between 2013-2020):
There are two major barriers identified in the literature that may prevent the effective use of PoCUS in the diagnosis of SBO. First, not every emergency physician has been trained on the use of PoCUS. Fortunately, two recent studies show that even minimally trained ED physicians can use it accurately. 8 Secondly, some surgeons have argued that PoCUS does not show the location of the obstruction accurately. This becomes a concern when the care team elects for surgical management of the patient’s SBO. However, recent evidence suggests that PoCUS may lead to quicker time to diagnosis and enteric tube insertion in conservative management. 8
Finally, how can learners use this technology? 5 Here are some specific sonographic findings to look for when evaluating a patient for SBO with US:
Figure 1. Dilatation of small bowel loops. Image courtesy Dr. Kavish Chandra
Figure 2. Altered intestinal peristalsis*. Image courtesy Dr. Kavish Chandra
Figure 3. – abnormal peristalsis “to and fro”9
References
Copyedited by Dr. Mandy Peach
Miranda Lees, Clinical Clerk II
Dalhousie Medicine New Brunswick, Saint John
Reviewed by Dr. Mandy Peach
Case
A 21yo G3P1A1 female at 6 weeks gestation presented to the Emergency Department with an 8 hour history of vaginal bleeding and abdominal pain. The bleeding is a mixture of bright red and brown blood with no clots, and the abdominal pain is episodic cramping in her suprapubic region.
Her obstetrical history is significant for 2 prior pregnancies, the first of which was carried to term with an uncomplicated vaginal delivery, and the second of which had resulted in a spontaneous abortion at 6 weeks gestation. She is otherwise healthy. The patient noted with both prior pregnancies she had similar vaginal bleeding around 6-8 weeks gestation. She was given RhoGAM due to her Rh- blood type.
On assessment the patient appeared well with all vital signs within normal limits. On physical exam bowel sounds were present, the abdomen was tympanic to percussion, and pain on palpation was present in the patient’s suprapubic region.
Differential for life threatening causes of vaginal bleeding in pregnancy
<20 weeks gestation | >20 weeks gestation |
ruptured ectopic pregnancy | placental abruption |
retained products of conception | placenta previa |
complication of termination | post partum hemorrhage |
Other causes for vaginal bleeding to consider in pregnancy and in non-pregnant patients
Spontaneous abortion |
Acute heavy menstrual bleeding |
Genitourinary trauma |
Uterine arteriovenous malformation |
Ruptured ovarian cyst |
Ovarian torsion |
Pelvic Inflammatory Disease |
Fibroids |
Polyps |
Foreign body |
Coagulation disorder |
Medication related |
Gynecologic malignancy |
Investigations
A βhCG was ordered to confirm pregnancy and bedside ultrasound was done to look for intrauterine pregnancy.
Transabdominal ultrasound showed the following:
The presence of a gestational sac within the uterus and a fetal heartbeat within the fetal pole confirmed a viable intrauterine pregnancy (IUP). The patient was diagnosed with threatened abortion.
Spontaneous Abortion-an overview
Spontaneous abortion is one of the most common complications of pregnancy, occurring in 17-22% of pregnancies2 and is defined as loss of pregnancy prior to 20 weeks gestation, occurring most often in the first trimester3. There are 3 primary causes: chromosomal abnormalities in the fetus, maternal anatomic abnormalities, and trauma.3
Risk factors for spontaneous abortion
age (below 20 and above 35) |
moderate to severe bleeding (especially if passage of clots) |
prior pregnancy loss |
maternal comorbidities (DM, autoimmune conditions, obesity, thyroid disease) |
infection (notably parvovirus, CMV and untreated syphilis) |
teratogenic medications |
maternal radiation exposure |
maternal smoking |
caffeine |
alcohol use |
Classification4
Missed abortion is characterized by an asymptomatic death of the fetus with a lack of contractions to push out the products of conception.5
Clinical presentation
Spontaneous abortion most commonly presents with vaginal bleeding and cramping, ranging from mild to severe1. However, most women with first-trimester bleeding will not undergo spontaneous abortion1. Bleeding associated with spontaneous abortion often involves passage of clots or fetal tissue, and the cramping can be constant or intermittent, often worse with passage of tissue1.
Diagnosis
Confirmation of spontaneous abortion requires pelvic ultrasound.
In patients with a prior ultrasound showing intrauterine pregnancy, diagnosis of spontaneous abortion can be made if a subsequent ultrasound shows no intrauterine pregnancy or a loss of previously-seen fetal heartbeat1.
In patients with a prior ultrasound showing intrauterine pregnancy with no fetal heartbeat, spontaneous abortion is diagnosed based on the following1:
Case conclusion
The patient was treated with IM RhoGAM, a formal pelvic and transvaginal ultrasound was arranged for the next day, and she was discharged home. The follow-up ultrasound showed a gestational sac present in the uterus, an embryo with crown rump length of 8.1mm and the presence of a fetal heartbeat.
References
Reviewed and Edited by Dr. David Lewis
All case histories are illustrative and not based on any individual
A 25yr old male presents with a 3 day history of a red swollen foot following an insect bite. He has no past medical history. On examination there is some erythema and swelling on the dorsum of the left foot. Palpation is very tender.
You are aware of recommended guidelines that advise I&D for purulent infections and decide to proceed with the procedure. Despite trying to freeze the area with lidocaine, the procedure is still painful and no pus is drained. You point to the minimal serosanguinous exudate and sheepishly suggest to the patient that the I&D was successful and that a course of antibiotics will resolve this issue.
Skin and soft tissue infections (SSTIs) have a variety of potential causes, ranging in severity from mild infections like cellulitis to abscess all the way to life-threatening causes like necrotizing fasciitis.1 SSTIs are commonly encountered in the emergency department, with cellulitis and abscesses being the two most common.2 It is important to be able to recognize SSTIs and provide appropriate treatment. Abscesses require invasive management, whereas cellulitis is treated with systemic therapies; therefore, it is important to be able distinguish the different between the two types. Doing so can be difficult because of the hidden nature of abscesses. However, ultrasound can be a useful tool in establishing the presence of an abscess. This article is a review of the clinical approach and treatment for SSTIs, focusing on cellulitis and abscesses, as well as the use of ultrasound in helping to establish the diagnosis.
Clinical suspicion is the initial step in the diagnosis of SSTIs. These infections have multiple causes; therefore, obtaining a detailed history is crucial. Information about immunocompromised state, place of residence, travel, any recent trauma or surgery, previous antimicrobial use, lifestyle, hobbies, and animal bites is essential to developing an adequate differential diagnosis.3
A good understanding of the normal skin flora and common infectious organisms is key to assessing SSTIs. The most commons organisms implicated in SSTIs are Staphylococcus aureus and Streptococcus species.4-6 Methicillin resistant S. aureus (MRSA) being an important strain that has increased in prevalence in the past 20 years. Risk factors such as presence of abscess, intravenous drug use, previous MRSA status, antibiotics within 8 weeks, diabetes mellitus, and previous hospital admission within the last year increase the likelihood of the infection being cause by MRSA.4-6
Physical examination findings are crucial for establishing the presence of an SSTI; the typical criteria are a superficial lesion with the classic inflammatory findings of redness (rubor), swelling (tumor), warmth (calor), and pain (dolor).1,2,7 An abscess is defined as a fluctuant mass of puss localized and buried within a tissue, organ, or potential space; however, clinically it can be hard to determine to presence of this mass.2,7 Other associated signs and symptoms, such as crepitus, bullae, and hemorrhage, may be present upon diagnosis or may develop later during the course.2,7 Due to overlapping clinical presentations of the different SSTIs, it can be difficult to differentiate between them.
Due to the similarities between different SSTI cutaneous findings and their different treatments, it is important to establish if there is an abscess present. It was common, before the introduction of ultrasound, to perform a blind needle aspiration of the infected area in order to determine the presence/absence of an abscess.8,9 However, this subjects that patient to the risks of an invasive procedure as well as pain. On the other hand, treating infection with empiric antibiotics in the presence of an unknown abscess delays drainage and allows for potential worsening of the infection.8,9
A study by Tayal et al. demonstrated that the use of ultrasound was beneficial in patients who had both low and high pretest probability for needing incision and drainage. In patients suspected of having simple cellulitis (low pretest), ultrasound was used to change management in over half of participants; establishing the need for drainage due to imaging of a fluid collection. The opposite was true in the patients suspected of having an abscess (high pretest); the study found that ultrasound was able to determine that more than half of this group did not need drainage, because of the absence of a fluid collection on imaging.10 Other studies have had similar findings, but the percent change in management was slightly lower.11
A study by Barbic et al. demonstrated that POCUS provided a rapid, non-invasive, painless, and easily repeatable test, that distinguished between abscess and cellulitis in the vast majority of cases. Their analysis concluded that POCUS had a sensitivity of 96.2% and a specificity of 82.9% in diagnosing the presence of an abscess.12 They concluded that POCUS can accurately diagnose abscess in paediatric and adult populations and is likely superior to clinical examination.12
Classic finding for cellulitis (but not specific to cellulitis). There will be hyperechoic lobules of subcutaneous fat surrounded by relatively hypoechoic inflammatory fluid.13
Classic finding for an abscess; have a rounded shape of anechoic or hypoechoic fluid collection, and there will be surrounding areas of cobblestones from the overlying cellulitis.13 As well, there should be no color flow if doppler is applied to the area (helping to distinguish from lymph node or vessel).14
Because you do not want to miss it! Findings via ‘STAFF’; subcutaneous thickening, air, and fascial fluid.14 Note, that ultrasound does not to exclude the diagnosis. Also need clinical correlation to increase suspicion of such a serious infection.15
According to The Infectious Diseases Society of America (2014) guidelines, management of SSTIs is differentiated based on the presence/absence of purulence (i.e. abscess/fluid collection). They recommend that all purulent infections be treated with incision and drainage, with more severe infections (signs of systemic involvement) being cultured with sensitivities in order to add antibiotics to the treatment.16 Otherwise, non-purulent infections are to be treated with systemic antibiotics; the severity of the infection determining the route and choice of agent.16
Antibiotic therapy, in addition to incision and drainage of a skin abscess, is suggested for patients with any of the following:17
Horizon Health’s local trends recommend the following (see guideline or Spectrum app for full details)
Severity of Infection |
|||
Antibiotic |
Mild |
Moderate |
Severe |
Cephalexin 500 – 1000mg PO q6h x 5 days |
ceFAZolin 2 g IV q8h x 5 days |
ceFAZolin 2 g IV q8h +/- Clindamycin 900 mg IV q8h |
|
If true beta-lactam allergy |
Cefuroxime 500 mg PO BID or TID x 5 days |
Clindamycin 600-900 mg IV q8h x5 days |
|
If MRSA suspected |
Septra 800/160 mg or 1600/320 mg PO q12h x 5 days |
Vancomycin 25-30 mg/kg IV once then 15mg/kg IV q8 to q12h x 5 days |
ADD Vancomycin 25-30 mg/kg IV once then 15mg/kg IV q8 to q12h |
Some research is suggesting that POCUS can take the assessment of abscesses one step-further and impact management based on the depth and size of the fluid collection seen in imaging. Russell et al. found that abscesses less than 0.4cm below the skin surface could be effectively treated without incision and drainage.18 Another study found that patients, with skin abscesses less than or equal to 5cm in diameter, treatment with oral antibiotics in combination with incision and drainage had improved short-term outcomes compared to those patients treated with the procedure alone.18 While as mentioned above, UpToDate, suggests that antibiotics be used in single abscess greater than 2 cm in size. As well, research has found that ultrasound guided incision and drainage provides lower failure rates (less recurrent infections or multiple incisions) compared to blind incision and drainage. Likely due to better visualization of the abscess and more adequate initial drainage.19
There are some limitations to POCUS for SSTIs: ultrasound imaging and interpretation rely on the user’s ability to obtain high-quality images in order to assess whether an abscess is present. It is important for the user to be familiar with different findings on ultrasound to guide appropriate treatment. An abscess may appear hypoechoic, hyperechoic, or anechoic (depending on tissue contents), and usually has posterior acoustic enhancement.19 Determining if it is drainable can be difficult due to this variability in imaging, and it is also quite common for early abscesses to present like cellulitis with erythema, no fluctuance, and an ultrasound that is negative for a fluid collection.20 In cases of a suspected evolving abscess, sometimes referred to as a non-ripe abscess, supportive care, including warm compresses, pain control, and close follow-up, is recommended.20 The practitioner may treat this like cellulitis; however, the patient may return with perceived failure of therapy if discharge advice does not include the possibility of of an abscess forming over time.