Background: Parotitis caused by nontuberculous mycobacteria, a very rare disease entity, has never been reported to be caused by Mycobacterium fortuitum (M. fortuitum) in the literature.
Methods and results: An 8-year-old girl was seen with painful swelling of the right parotid gland despite antibiotic treatment of more than 1 month. Elevated serum amylase activity and diffuse contrast-enhanced CT of the parotid gland confirmed the diagnosis of parotitis. Histopathological study of specimens taken from the right parotid tail mass showed granulomatous inflammation with acid-fast positive bacilli; culture later confirmed M. fortuitum. After administration of clarithromycin and ciprofloxacin for 9 consecutive months, the parotitis and parotid tail mass were completely resolved at follow-up examination.
Conclusion: To our knowledge, this is the first case report of parotitis caused by M. fortuitum and its successful medical treatment.