Atypical mycobacterial infection

Classically a cold abscess, usually in the neck. Ingested soil?

Overlying skin can become discoloured, and ultimately fistulation may occur. Child is usually systemically well.

Blood tests are normal. Mantoux testing can be positive due to cross reaction with BCG. Fine needle aspiration may be most appropriate.

Drug treatment needs to be prolonged and recurrence is common.

Surgery can be tricky.