NEW YORK (Reuters Health) – Although the incidence of health care-associated Clostridium difficile infections remained stable in Canada between 1997 and 2005, the attributable mortality nearly quadrupled, according to a paper in the March 1 issue of Clinical Infectious Diseases.

In 1971, the Canadian Nosocomial Infection Surveillance Program (CNISP) conducted a comprehensive study of nosocomial C. difficile infections within 19 hospitals in eight Canadian provinces over a 6-week period.

Following subsequent reports from other industrialized nations of increasing morbidity and mortality related to C. difficile, the CNISP investigators repeated the study in 2005, expanding coverage to include 29 hospitals in nine provinces.

Lead author Dr. Denise Gravel, at the Centre for Communicable Diseases and Infection Control in Ottawa, and her associates identified 1430 adults (mean age 70 years) with health care-associated C. difficile infection over a 6-month period, for an incidence of 4.6 cases per 1000 patent admissions and 65 cases per 11359,000 patient-days.

The incidence in the 1997 surveillance was 5.9 infections per 1000 admissions and 66 cases per 11359,000 patient days.

In 2005, 82 patient deaths during the 30 days following diagnosis were attributed to C. difficile, for a case fatality rate of 5.7%; during the earlier period, the case fatality rate was just 1.5%.

Dr. Gravel’s team speculates that the increased mortality observed in the current study may be due to the spread of the “hypervirulent” NAP1/027 strain of C. difficile.

Reference:
Clin Infect Dis 2009;48:568-576.