An insidious case of infectious mononucleosis presenting with acute appendicitis diagnosed postoperatively: a case report.

Infectious mononucleosis (IM) is a syndrome caused by the Epstein-Barr virus. IM typically presents with fever, pharyngitis and lymphadenopathy. Rarely, it can cause acute appendicitis. We report the case of a 19-year-old female presenting with a chief complaint of colicky, non-radiating abdominal pain for 2 days. Abdominal examination revealed rebound tenderness in right iliac fossa tenderness and splenomegaly. The diagnosis of acute appendicitis was confirmed by computed tomography. She underwent laparoscopic appendectomy and mesenteric lymph node biopsy. She was later diagnosed with IM based on laboratory findings and histopathology results. She received a course of intravenous acyclovir and was discharged. This shows that IM may present with acute appendicitis as the initial presentation and may not be accompanied by any other significant symptoms of IM.