title: The undiagnosed cases of Clostridium difficile infection in a whole nation: where is the problem?
abstract: Underdiagnosis of Clostridium difficile infection (CDI) because of lack of clinical suspicion or the use of non-sensitive diagnostic techniques is a known problem whose real magnitude has not yet been quantified. In order to estimate the extent of this underdiagnosis, we performed C. difficile cultures on all unformed stool specimens sent-irrespective of the type of request-to a series of laboratories in Spain on a single day. The specimens were cultured, and isolates were characterized at a central reference laboratory. A total of 807 specimens from 730 patients aged ≥ 2 years were selected from 118 laboratories covering 75.4% of the Spanish population. The estimated rate of hospital-acquired CDI was 2.4 episodes per 1000 admissions or 3.8 episodes per 10,000 patient-days. Only half of the episodes occurred in patients hospitalized for >2 days. Two of every three episodes went undiagnosed or were misdiagnosed, owing to non-sensitive diagnostic tests (19.0%) or lack of clinical suspicion and request (47.6%; mostly young people or non-hospitalized patients). The main ribotypes were 014/020 (20.5%), 001 (18.2%), and 126/078 (18.2%). No ribotype 027 strains were detected. Strains were fully susceptible to metronidazole and vancomycin. CDI was underdiagnosed in diarrhoeic stools in a high proportion of episodes, owing to the use of non-sensitive techniques or lack of clinical suspicion, particularly in people aged <65 years or patients with community-acquired diarrhoea. C. difficile toxins should be routinely sought in unformed stools of any origin sent for microbiological diagnosis. The ribotype 027 clone has not yet disseminated in Spain.
authors.affiliation: Clinical Microbiology and Infectious Diseases Department, Hospital General Universitario Gregorio Marañón, Madrid, Spain. luisalcala@efd.net
authors.forename: L
authors.initials: L
authors.lastname: Alcalá
authors.forename: A
authors.initials: A
authors.lastname: Martín
authors.forename: M
authors.initials: M
authors.lastname: Marín
authors.forename: M
authors.initials: M
authors.lastname: Sánchez-Somolinos
authors.forename: P
authors.initials: P
authors.lastname: Catalán
authors.forename: T
authors.initials: T
authors.lastname: Peláez
authors.forename: E
authors.initials: E
authors.lastname: Bouza
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D019411:Clinical Laboratory Techniques / Q000379:methods / Q000592:standards; D016360:Clostridioides difficile / Q000302:isolation & purification*; D003015:Clostridium Infections / Q000175:diagnosis* / Q000453:epidemiology*; D003951:Diagnostic Errors / Q000706:statistics & numerical data; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013030:Spain / Q000453:epidemiology; D055815:Young Adult