Arch. Gerontol. Geriatr., 13 (1991) 255-262 © 1991 Elsevier Science Publishers B.V. All rights reserved 0167-4943/91/$03.50 AGG00415 255 Clostridium difficile infection in a geriatric ward Ingrid Monsieur a, Tony Mets a, Sabine Lauwers b, Veerle De Bock a and Michel Delm6e c Division of Geriatrics, b Department of Microbiology, Academic Hospital, Free University of Brussels (V.U.B.), Brussels, and c Microbiology Unit, University of Louvain, Brussels, Belgium (Received 10 October 1990; revised version received 25 April 1991; accepted 14 June 1991) Summary In a prospective, longitudinal study we searched for the presence of Clostridium difficile in the stools of 100 consecutively hospitalized elderly patients (mean age: 82; SD: 9.5 years). C. difficile was found on admission in 6 patients, 3 of whom were asymptomatic carriers. Ten patients acquired C. difficile during hospitalization. Four different types of C. difficile were isolated. The various types were clustered in time, indicating that the infection was acquired from the environment. Aged; Clostridium difficile; Clostridium difficile-associated diarrhea; Elderly; Geriatrics; Nosocomial infection Introduction Clostridium difficile was isolated for the first time in 1935 from the faeces of children (Hall and O'Toole, 1935). It was only in 1978, however, that its etiological role in pseudomembranous colitis was recognized (Bartlett et al., 1978). Since then C. difficile has been associated with outbreaks of less severe colitis and with diarrhea in hospitalized patients receiving antimicrobial therapy. For several clusters of cases or large outbreaks in hospitals direct infection from the environ- ment has been suggested (Mulligan et al., 1979; Fekety et al., 1981; Greenfield et al., 1981; Delm6e et al., 1986a; Heard et al., 1986; McFarland et al., 1989). Geriatric patients seem to be more susceptible to C. difficile infection and up to 30% of the patients in chronic care facilities have been found to be carriers (Bender et al., 1986). Most studies are cross-sections of populations, set up at the moment of an outbreak of symptomatic C. difficile infection. Only limited informa- tion is available about the dynamics of C. difficile infection in geriatric hospitalized patients. Therefore we undertook a prospective, longitudinal study in order to Correspondence to: Dr. T. Mets, Geriatrics, A.Z.-V.U.B., Laarbeeklaan 101, B-1090 Brussels, Belgium.