Transmission of tuberculosis to hospital workers by a patient with AIDS.

A patient with acquired immunodeficiency syndrome (AIDS) was admitted to a hospital with cough and fever and after 29 days was transferred to a hospice. He was eventually shown to have active pulmonary tuberculosis. This diagnosis was obscured clinically by simultaneous infection with Pneumocystis carinii and Mycobacterium avium complex (MAC). Laboratory recognition of Mycobacterium tuberculosis was delayed because of overgrowth of cultures by MAC but was later established using DNA probe techniques. Thirty (19 percent) of 158 health care workers who had been exposed to this patient had conversion of their tuberculin skin tests. Diagnostic difficulties and nosocomial transmission of tuberculosis may occur when patients with AIDS have mixed mycobacterial infections.