Mycobacterium peregrinum infection in a patient with AIDS.

The patient, a 30-year-old housewife, visited a nearby doctor in mid August 2002 because of weight loss and neck swelling. HIV tests done at the hospital were positive. She was referred to and admitted to our hospital on October 2 for detailed examination and treatment of the neck tumor. A coat of epithelial debris extended from the oral cavity to the pharynx and an abscess and a fistula were found in the left tonsil. After hospitalization, an abscess culture revealed the presence of acid-fast bacteria, which was identified as Mycobacterium peregrinum. Treatment with imipenem and clarithromycin resulted in the normalization of CRP (0.1 mg/dl), on day 5 of treatment. The patient was discharged from the hospital after treatment for 2 weeks with imipenem and clarithromycin. Thereafter, the patient received continuous treatment with faropenem and clarithromycin for 4 more weeks, and has shown no signs of recurrence for 11 months to date. Only a few cases of infection with this bacterial strain have been reported. This infection is difficult to treat because most antituberculosis agents are not effective against it and there is limited availability of effective antibiotics. Medical treatment of infection caused by Mycobacterium peregrinum may be useful in such cases.