Underdiagnosis of Clostridium difficile across Europe: the European, multicentre, prospective, biannual, point-prevalence study of Clostridium difficile infection in hospitalised patients with diarrhoea (EUCLID)
Abstract
Background Variations in testing for Clostridium difficile infection can hinder patients' care, increase the risk of transmission, and skew epidemiological data. We aimed to measure the underdiagnosis of C difficile infection across Europe.
Methods We did a questionnaire-based study at 482 participating hospitals across 20 European countries. Hospitals were questioned about their methods and testing policy for C difficile infection during the periods September, 2011, to August, 2012, and September, 2012, to August, 2013.
On one day in winter, 2012-13 (December, 2012, or January, 2013), and summer, 2013 (July or August), every hospital sent all diarrhoeal samples submitted to their microbiology laboratory to a national coordinating laboratory for standardised testing of C difficile infection. Our primary outcome measures were the rates of testing for and cases of C difficile infection per 10 000 patient bed-days.
Results of local and national C difficile infection testing were compared with each other. If the result was positive at the national laboratory but negative at the local hospital, the result was classified as undiagnosed C difficile infection.
We compared differences in proportions with the Mann-Whitney test, or McNemar's test if data were matched. Findings During the study period, participating hospitals reported a mean of 65.8 tests (country range 4. 6-223.3) for C difficile infection per 10 000 patient-bed days and a mean of 7.0 cases (country range 0.7-28.7) of C difficile infection per 10 000 patient-bed days.
Only two-fifths of hospitals reported using optimum methods for testing of C difficile infection (defined by European guidelines), although the number of participating hospitals using optimum methods increased during the study period, from 152 (32%) of 468 in 2011-12 to 205 (48%) of 428 in 2012-13.