Drug resistance of Mycobacterium tuberculosis strains isolated from HIV-infected Italian patients: preliminary report from a multicentric study. The Italian Tuberculosis Drug Resistance Study Group.

A multicentric prospective study started in March '93 to describe both initial and acquired resistance of Mycobacterium Tuberculosis in Italian HIV+ patients (pts.) to first line drugs: Rifampin (R), Isoniazid (I), Pyrazinamide (P), Ethambutol (E), Streptomycin (S). All tuberculosis (TB) cases diagnosed in HIV+ patients (pts.) were included, along with clinical-anamnestical data. Drug-susceptibility tests were performed centrally. Preliminary results indicate an overall low frequency of TB resistance to first line drugs: R = 2%, P = 4%, S = 9%, I/E = none. However, a relevant nosocomial outbreak of multiple drug resistant (DR) TB was detected. This finding, along with some previous Italian reports of DR-TB clusters, may herald a further spread of DR-TB. Surveillance, therefore, is mandatory in Italy from now on.