Review article

Laboratory detection of Clostridium difficile in animals: a review

Jana Avberšek orcid.org/0000-0003-2107-7763 ; Veterinary Faculty, University of Ljubljana, Slovenia

Abstract

Clostridium difficile (C. difficile) is an important pathogen responsible for nosocomial intestinal infections in humans. The number of community-acquired infections in patients without risk factors for infection has been increasing. In these cases, animals could act as a reservoir of C. difficile, which may be present in the animal digestive tract as a causative agent of enterocolitis and diarrhoea or as commensal bacteria. The overlap of human and animal C. difficile genotypes indicates the zoonotic potential of the bacterium, and specific genotypes capable of causing severe infections in animals and humans have been reported. Different methods are used in human medicine for laboratory detection of C. difficile, and a variety of commercial tests are available. Diagnostic methods are based on cultivation of C. difficile on selective media, detection of C. difficile toxins and molecular tests. All these methods could be potentially used in veterinary medicine; however, with the exception of culture methods, the use of commercial tests is limited for testing animal samples, as the test results often poorly correlate with culture results or are not capable of detecting the variant C. difficile toxinotypes that are common in animals. Currently, no testing algorithm is available for the detection of C. difficile in animals; the gold standard is toxigenic culture. Pre-enrichment in selective broth is the method of choice, though recently comparable results were obtained with direct culture on chromogenic agar Chrom ID C. difficile. Enzyme immunoassay (EIA) toxin tests have a lower sensitivity for animal samples, therefore the use of EIAs for human diagnosis is not recommended without prior validation on animal samples. As in human medicine, in-house molecular methods are useful for rapid detection of C. difficile. Real- time PCR (rtPCR) assays are not adequate as a stand-alone test; however, implementation of a one-day pre-enrichment step prior to rtPCR evidently increased method sensitivity. The sensitivity of rtPCR assays could also be improved with modified DNA extraction procedures, including repeated bead-beating.

Keywords

Clostridium difficile; laboratory diagnostics; animals

Hrčak ID:

222681

URI

https://hrcak.srce.hr/222681

Publication date:

4.12.2017.

Article data in other languages: croatian

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