A Peanut Problem or Pimple Popper Predicament – A Resident Clinical Pearl
Grace Dao PGY1
Family Medicine, Dalhousie University
Saint John, NB
Reviewed by: Dr. Chris Vaillancourt
Copyedited by: Dr. Mandy Peach
Case Presentation
A 30-year-old otherwise healthy female presented to the ED with concerns about an “allergic reaction” to peanut butter. She reported that she woke 30 minutes prior to her presentation in the ED with a severely swollen red and disfigured lip. Her face had looked normal upon going to bed the evening prior. Her last meal was a peanut butter sandwich, which she eats frequently without difficulty. She described having some “wheezes” and “chest tightness” to the triage RN. When seen by writer, she denied any trouble breathing. She denied any issues the night prior before going to bed. She denied any GI upset, such as cramping, nausea, vomiting or diarrhea. Besides the swollen lip, she denied noticing any other skin changes; she denied any itchy sensation. Past medical history was unremarkable; she had no history of prior allergic reaction and no known allergies. She took no medications. Review of systems was negative, besides she noted that there was pimple at the base of her nose that she had “popped” yesterday.
On exam, all vitals were within normal limits besides a HR of 110. Respiratory exam revealed no obvious stridor or increased work of breathing; there was no swelling of the tongue or uvula on inspection of the mouth, clear air entry and exit were appreciated bilaterally. A faint wheeze was appreciated bilaterally. Cardiovascular and abdominal examinations were within normal limits. A skin exam revealed a diffusely red and swollen upper lip, with skin the above the vermillion border also showing swelling and redness. Increased erythema/pus at the R nostril sill was appreciated in the area of the previously popped pimple. The lip was tender and very warm to the touch.
With 2 system involvement (lip swelling and wheezes on respiratory exam); she was treated as anaphylaxis initially and given 0.5 mg Epinephrine IM, which did not lead to any change in her symptoms. However, it would be quite unusual for an IgE mediated reaction to present this late after ingestion. A peanut allergy especially, as most of these present before age 3.
Initial bloodwork showed a normal CBC, Cr and electrolytes. CRP was elevated at 67.1. Due to no change in symptoms with anaphylaxis treatment and concerns re an infectious etiology a CT facial bones was ordered after discussion with the radiologist on call. CT report showed a broad zone of cellulitis with an evolving central abscess. ENT was consulted who reported that incision and drainage was required, and that the infection likely came from the popped pimple. They performed an incision and drainage of the abscess in the ED, took wound cultures and started empiric antibiotics, and arranged for outpatient follow-up. In discussion with the ENT, it was noted that this presentation is typical of CA-MRSA cellulitis, and, thus, antibiotics to cover MSRA were required.
Anaphylaxis
While not the outcome in this case, it is important to be familiar with the various constellation of symptoms/signs that make anaphylaxis a likely and the initial management of this “can’t miss” diagnosis, which are outlined in the included figures1,2.
Lip Cellulitis and Abscess
Interestingly, after this case, a case study of a similar presentation was found in the literature where a MRSA lip infection was initially misdiagnosed as angioedema/anaphylaxis3. The diagnosis was discovered later, after the patient was unresponsive to anaphylaxis treatment and a history of a popping a pimple on their chin the day prior was elicited. Because Methicillin-resistant Staphylococcus aureus (MRSA) soft tissue infection also has a characteristic presentation of erythema, edema, and often, areas of fluctuance it can have a similar appearance to the typical angioedema that can be found in anaphylaxis.
See Reference 3. This CT was performed after incision and drainage; thus, no abscess is appreciated
While it is important to be vigilant towards the presentation of anaphylaxis, cellulitis is another diagnosis that it important not to miss4. Like other infections, complications of cellulitis include bacteremia, endocarditis, septic arthritis, osteomyelitis, metastatic infection, sepsis and toxic shock syndrome. In patients with suspected erysipelas or cellulitis it is important to consider the possibility of an abscess, which requires incision and drainage. Findings in keeping with a skin abscess would be a painful, erythematous, fluctuant nodule.
The central face is not the most common area to develop cellulitis; however, it is an important area to recognize cellulitis. Untreated cellulitis in this area, can lead to septic cavernous thrombosis because the veins in this region are valveless.
Other diagnoses to consider for angioedema without history consistent with IgE mediated reaction or infection:
- Hereditary or acquired angioedema
- Mast cell disorder
- Idiopathic angioedema
Bottom Line: Always consider anaphylaxis in someone with apparent lip angioedema. However, it is also important to keep infection on the differential for a swollen lip, particularly if symptoms are not responding to therapy. Asking about prior injuries/skin lesions in the previous days can help clarify likelihood of infection. Also, as a personal takeaway, I should probably stop popping pimples.
References:
- Sampson, H. A. , Munoz-Furlong A., Campbell, R.L., et al. (2016). Second symposium on the definition and management of anaphylaxis: Summary report: Second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network Symposium. J Allergy Clin Immunol 2006; 117:391. https://doi.org/10.1016/j.jaci.2005.12.1303
- Campbell, R.L. & Kelso, J.M. (2021). Anaphylaxis: Acute diagnosis. UpToDate. Retrieved December 30th, 2021 from : https://www.uptodate.com/contents/anaphylaxis-acute-diagnosis?search=anaphylaxis&topicRef=392&source=see_link#H1929228973
- Lucerna, A. R., Espinosa, J., & Darlington, A.M. (2015). Methicillin-resistant Staphylococcus Aureus Lip Infection Mimicking Angioedema. The Journal of Emergency Medicine 49 (1), 8-11 https://doi.org/10.1016/j.jemermed.2014.12.022.
- Spelman, D. & Baddour, L.M. (2021). Cellulitis and skin abscess: Epidemiology, microbiology, clinical manifestations, and diagnosis. UpToDate. Retrieved January 2nd, 2022 from: https://www.uptodate.com/contents/cellulitis-and-skin-abscess-epidemiology-microbiology-clinical-manifestations-and-diagnosis?search=cellulitis%20&source=search_result&selectedTitle=3~150&usage_type=default&display_rank=2#H1368100182