['Reports from the United States that urinary tract infections (UTI) are more common in homosexual than in heterosexual men have not been confirmed in Europe. The occurrence of several UTI in men infected with HIV-1 has been recorded in The Netherlands. We therefore analysed the relationship between the presence of bacteriuria and the immune status (CD4+ cell count) in these HIV-1-infected patients.', 'Urinary cultures were obtained prospectively for 2 years, during the first visit and every 6 months thereafter, when signs and symptoms of UTI occurred and when patients had fever of unknown origin. CD4+ cell counts were measured at the same time.', 'The study was performed at the University Hospital, Utrecht, The Netherlands.', 'One hundred and thirty HIV-1-infected men attended our hospital. Data from 98 were analysed. Eighty-nine (91%) of these men were either homo- or bisexual.', 'Positive urinary culture.', 'Group 1 (CD4+ cell count less than 200 x 10(6)/l) consisted of 47 patients; 30% had at least one period of bacteriuria, with 21 episodes. Group 2 (CD4+ cell count 200-500 x 10(6)/l) consisted of 27 patients; 11% had at least one period of bacteriuria, with five episodes. We did not find bacteriuria in the 24 patients in group 3 (CD4+ cell count greater than 500 x 10(6)/l). The rate of bacteriuria per patient-month, 4 (group 1) versus 2 (group 2), differed significantly (P less than 0.001). A significant relationship between CD4+ cell count and bacteriuria was found (P = 0.00003); no relationship, however, was found with anal intercourse, hospitalization, Karnofsky score, follow-up, or age.'] Is bacteriuria in men infected with HIV-1 related to their immune status ( CD4+ cell count )?