EM@3AM - November 19, 2022 - By Devin Morris; Colin Danko
Reviewed by: Sophia Görgens; Cassandra Mackey; Brit Long; Alex Koyfman
Summary and Pearls
- If a patient presents with mononucleosis-like syndrome but has abrupt onset of symptoms, diarrhea, or mucocutaneous lesions, consider HIV work up
- Axillary, inguinal, or posterior cervical adenopathy, palatal petechiae, and splenomegaly greatly increase likelihood of mononucleosis in the correct clinical setting
- Splenic rupture is a rare but potentially fatal effect of IM. The greatest risk is in males under the age of 30, within 4 weeks of symptom onset. Avoid contact sports for 4 weeks and give return precautions for any new-onset abdominal pain
- False-negative rate of heterophile antibody testing can be as high as 25% in first week of symptoms, consider repeat test or EBV specific antibody testing, especially for pregnant patients