A study of Clostridium difficile positivity using multistep algorithm of testings in a tertiary care hospital

Abstract

Clostridium difficile is an anaerobic, spore bearing bacteria can colonize hospitalized patients commonly. Toxin producing strains are an important cause of nosocomial diarrhea. Though various testing methods are available for the diagnosis of C. difficile infection (CDI) but, correct diagnosis is still a challenge for laboratories. To study the positivity of the infection by multiple testing methods available. This is an observational study. A total of 1429 freshly passed stool samples received in the Department of Microbiology from February 2019-May 2020 were included in the study. Further, the samples (1415) were tested for presence of Glutamate Dehydrogenase antigen (GDH Ag), toxin A, toxin B by an ICT (immunochromatography test) from Vittassay. A total of 48 samples were tested by GeneXpert (Cepheid) PCR (Polymerase Chain Reaction). Out of these, 14 samples were tested by PCR alone &34 samples were tested by both ICT & PCR. A total of 188(13.2%) samples received, from 165 patients including 94(57%) male patients & 71(43%) female patients, were found positive for CDI. Out of these, 184(13%) samples were found positive for GDH Ag screening in ICT. Among, 48 PCR tested samples, 5(10.4%) were detected positive for tcdtB gene. A total of 97(6.8%) samples showed the presence of toxins. Multiple algorithm of testings is required to increase the sensitivity of the diagnosis, but high cost is a limiting factor in the developing countries.