Mycobacterium avium intracellulare as a marker of human immunodeficiency virus disease.

Between January 1981 and December 1986, 4,178 patients were cultured for mycobacteria at a community teaching hospital in Hartford. The number of patients with positive cultures totaled 278 (6.65%). Mycobacterium other than tuberculosis (MOTT) was isolated from 228 (82%). MOTT isolation increased yearly from 1.5% of the patients in 1981 to 14.5% of the patients in 1986. Mycobacterium avium intracellulare (MAI) was the most common MOTT species isolated (197/228). Fifty-nine patients were under the age of 50, but 23 had predisposing factors for MOTT. Of the 36 who did not have an underlying condition, 25 had the human immunodeficiency virus (HIV). The isolation of MAI preceded the diagnosis of AIDS/ARC in nine patients, in 10 others it coincided with their diagnosis and in six it followed the diagnosis. Isolation of MAI in a patient under the age of 50 with no predisposing factors may suggest concommitant HIV disease.

A nosocomial outbreak of ampicillin-resistant Haemophilus influenzae type b in a geriatric unit.

A nosocomial outbreak of Haemophilus influenzae type b (Hib) bronchitis occurred in a geriatric unit. The three infected patients were grouped together in an isolation unit and treated. A prevalence survey was done by obtaining pharyngeal cultures from patients and staff in the unit. One patient and a nurse were asymptomatic pharyngeal carriers of Hib. One infected patient was bedridden, and his only known Hib contact was the nurse. Geographic clustering was the only significant risk factor, as determined by a case-control study. Carriers were treated with rifampin. The isolates were characterized for strain relatedness by using three methods. All produced beta-lactamase and all were serotype b. Plasmid profiles and restriction endonuclease analysis of bacterial DNA were performed; chromosomes were digested with the restriction endonucleases HindIII and HaeIII. Strains were confirmed as identical by using these methods and were different from two Hib control strains producing beta-lactamase. This study documents nosocomial transmission of Hib, by using molecular typing methods.