Low frequency of asymptomatic carriage of toxigenic Clostridium difficile in an acute care geriatric hospital: prospective cohort study in Switzerland.
BACKGROUND
The role of asymptomatic carriers of toxigenic Clostridium difficile (TCD) in nosocomial cross-transmission remains debatable. Moreover, its relevance in the elderly has been sparsely studied.


OBJECTIVE
To assess asymptomatic TCD carriage in an acute care geriatric population.


METHODS
We performed a prospective cohort study at the 296-bed geriatric hospital of the Geneva University Hospitals. We consecutively recruited all patients admitted to two 15-bed acute-care wards. Patients with C. difficile infection (CDI) or diarrhoea at admission were excluded. First bowel movement after admission and every two weeks thereafter were sampled. C. difficile toxin B gene was identified using real-time polymerase chain-reaction (BD MAX(TM)Cdiff). Asymptomatic TCD carriage was defined by the presence of the C. difficile toxin B gene without diarrhoea.


RESULTS
A total of 102 patients were admitted between March and June 2015. Two patients were excluded. Among the 100 patients included in the study, 63 were hospitalized and 1 had CDI in the previous year, and 36 were exposed to systemic antibiotics within 90 days prior to admission. Overall, 199 stool samples were collected (median 2 per patient, IQR 1-3). Asymptomatic TCD carriage was identified in two patients (2 %).


CONCLUSIONS
We found a low prevalence of asymptomatic TCD carriage in a geriatric population frequently exposed to antibiotics and healthcare. Our findings suggest that asymptomatic TCD carriage might contribute only marginally to nosocomial TCD cross-transmission in our and similar healthcare settings.
Infection Control Program, Geneva University Hospitals, 4, rue Gabrielle Perret-Gentil, 1211 Geneva, Switzerland ; Department of Infectious Diseases, Centro Hospitalar Lisboa Norte and Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal.
Daniela
D
Pires
Department of Geriatrics, Geneva University Hospitals, Geneva, Switzerland.
Virginie
V
Prendki
Central Laboratory of Bacteriology, Geneva University Hospitals, Geneva, Switzerland.
Gesuele
G
Renzi
Infection Control Program, Geneva University Hospitals, 4, rue Gabrielle Perret-Gentil, 1211 Geneva, Switzerland.
Carolina
C
Fankhauser
Infection Control Program, Geneva University Hospitals, 4, rue Gabrielle Perret-Gentil, 1211 Geneva, Switzerland.
Valerie
V
Sauvan
Infection Control Program, Geneva University Hospitals, 4, rue Gabrielle Perret-Gentil, 1211 Geneva, Switzerland ; Department of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland ; Faculty of Medicine, University of Geneva, Geneva, Switzerland.
Benedikt
B
Huttner
Central Laboratory of Bacteriology, Geneva University Hospitals, Geneva, Switzerland ; Department of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland ; Faculty of Medicine, University of Geneva, Geneva, Switzerland.
Jacques
J
Schrenzel
Infection Control Program, Geneva University Hospitals, 4, rue Gabrielle Perret-Gentil, 1211 Geneva, Switzerland ; Department of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland ; Faculty of Medicine, University of Geneva, Geneva, Switzerland.
Stephan
S
Harbarth
Asymptomatic; Clostridium difficile; Colonization