Nosocomial diarrhoea in adult medical patients: the role of Clostridium difficile in a North Italian acute care teaching hospital.

BACKGROUND

The number of patients with severe Clostridium difficile-associated diarrhoea (CDAD) increases. Health care facilities are requested to establish rates of nosocomially acquired CDAD (N-CDAD) to understand the impact of control or prevention measures, and the burden of N-CDAD on health care resources.

OBJECTIVE

Aim of the single-center surveillance project was to establish local prevalence rates of N-CDAD in adult acute care medical patients.

METHODS

For a period of at least one year, all diarrhoeal stools from inpatients of a general internal medicine ward were tested for Clostridium difficile toxin A. Case record files were retrospectively analysed and questionnaires were completed for patients with positive stool assays who met the case definitions.

RESULTS AND DISCUSSION

During the surveillance period, 2,610 medical patients had been acutely hospitalized. Stools had been submitted to the hospital laboratory from 163 patients (6.2%) because of diarrhoea and were screened for Clostridium difficile cytotoxin. Complete data sets were available for analysis from 150 patients. Of 137 identified potential cases, 77 (56.2%) met the case definitions for nosocomial diarrhoea. Thirteen of the patients with nosocomial diarrhoea (16.9%) were detected positive by the Clostridium difficile toxin A assay. The overall prevalence of N-CDAD among inpatients was 8.7 cases/100 diarrhoeal stools. The mean number ofN-CDAD cases was 62.3 cases/100,000 patient days and 5 cases/1,000 patient admissions. The mean age of N-CDAD patients was 79.4 years (range 71 to 92). All patients were given broad-spectrum antibiotics before acute diarrhoea developed. Four patients died for reasons not directly related to N-CDAD which confirms increased disease severity as an important risk factor.

CONCLUSIONS

This single-center surveillance project, which established N-CDAD rates at frequencies currently reported from international surveys, is useful as benchmark and will help in understanding patterns and impact of N-CDAD at the regional level.