Abdominal actinomycosis presenting as appendicitis: two case reports and review.

Abdominal actinomycosis (AA) is a rare infection caused by filamentous Gram-positive anaerobic bacteria Actinomyces. We report two cases of adults with AA who initially presented with clinical and radiological features of appendicitis. Both patients underwent appendicectomy with histopathology diagnostic for actinomycosis of the appendix and subsequently completed prolonged courses of oral penicillin. AA is a rare differential diagnosis for appendicitis and should be considered especially in patients with a chronic, indolent course and nonspecific abdominal symptoms. A high index of suspicion may avoid unnecessary surgery, as treatment with prolonged antibiotic therapy is very effective.