Refractory Cryptoglandular Perianal Abscess and Fistulas Due to Mycobacterium avium Infection in an Immunocompetent Adult.

Mycobacterium avium is a slow-growing nontuberculous mycobacterium (NTM) requiring prolonged treatment with multiple antimicrobials. It primarily affects immunocompromised patients and causes infection of the respiratory tract, skin, and soft tissue. While enteric carriage of M. avium has been reported, it has not been associated with clinical infection in immunocompetent hosts. To our knowledge, this is the first case report of a perirectal abscess caused by primary M. avium infection in an otherwise healthy patient and indicates the importance of considering NTMs as causative organisms in intraabdominal and enteric abscesses even among immunocompetent individuals when multiple courses of antibiotics are ineffective.