COMPARISON OF ENTEROTOXIN PRODUCTION, CYTOTOXIN PRODUCTION, SEROGROUPING, AND ANTIMICROBIAL SUSCEPTIBILITIES OF CLOSTRIDIUM-DIFFICILE STRAINS ISOLATED FROM AIDS AND HUMAN IMMUNODEFICIENCY VIRUS-NEGATIVE PATIENTS

We analyzed and compared Clostridium difficile strains isolated from diarrheic stools of 49 human immunodeficiency virus (HIV)-negative and 50 AIDS patients. Our results suggest that distribution patterns of serogroups are different in these two populations. Serogroup C (which has been previously reported to be very resistant to antimicrobial agents) represents 66.0 and 18.4% of the isolates from AIDS and HIV-negative patients, respectively (P < 0.001); the selection of serogroup C could be explained by multiple antibiotic pressure to which AIDS patients have been subjected.