# Acute Appendicitis in the Setting of Infectious Mononucleosis: A Case Report

## TL;DR

A young woman with infectious mononucleosis developed acute appendicitis, highlighting the importance of thorough diagnosis.

## Contribution

This case report highlights an atypical presentation of acute appendicitis caused by infectious mononucleosis.

## Key findings

- An 18-year-old female with infectious mononucleosis presented with acute appendicitis symptoms.
- A positive monospot test confirmed infectious mononucleosis as the underlying cause of appendicitis.
- The case emphasizes the need for thorough evaluation in diagnosing acute appendicitis.

## Abstract

Infectious mononucleosis (IM) is a viral illness caused by the Epstein-Barr virus that typically manifests with pharyngitis, lymphadenopathy, and fatigue. In rare cases, IM can cause acute appendicitis. We present the case of an 18-year-old female who arrived at the emergency department with worsening abdominal pain and an ongoing cough. Initial imaging showed a questionably dilated appendix, and a follow-up examination revealed cervical lymphadenopathy. She later returned to the ED with severe abdominal pain, clinical signs of acute appendicitis, and a positive monospot test, which led to an appendectomy. This case illustrates the need for complete history taking and thorough physical examination in patients with acute appendicitis, as their condition may be due to an atypical underlying cause.