Evaluation of glutamate dehydrogenase (GDH) and toxin A/B rapid tests for Clostridioides (prev. Clostridium) difficile diagnosis in a university hospital in Minas Gerais, Brazil

Braz J Microbiol. 2020 Sep;51(3):1139-1143. doi: 10.1007/s42770-020-00288-z. Epub 2020 May 4.

Abstract

Clostridioides (Clostridium) difficile is responsible for most cases of nosocomial diarrhea and, despite the high prevalence of the disease worldwide, the best laboratory diagnostic approach to diagnose C. difficile infection (CDI) is a subject of ongoing debate. Although the use of multiple tests is recommended, the cost of these algorithms commonly exceeds the affordability in some countries. Thus, to improve CDI diagnosis in a university hospital in Brazil, this study analyzed two immunochromatographic tests and one enzyme immunoassay (ELISA) to evaluate the detection of glutamate dehydrogenase (GDH) and A/B toxins of C. difficile. Stool samples of 89 adult patients presenting nosocomial diarrhea during hospitalization were included. The toxigenic culture was used as the reference method. GDH detection by both commercial tests showed high sensitivity (100%) and specificity (92.1%). On the other hand, toxin-based methods showed a sensitivity between 19.2 and 57.7%. In conclusion, the results suggest that rapid tests for GDH detection are not only suitable for CDI diagnosis as screening tests but also as a single method.

Keywords: Nosocomial diarrhea; Pseudomembranous colitis.

Publication types

  • Evaluation Study

MeSH terms

  • Bacterial Proteins / analysis*
  • Bacterial Proteins / metabolism
  • Bacterial Toxins / analysis*
  • Bacterial Toxins / metabolism
  • Brazil
  • Clostridioides
  • Clostridioides difficile / chemistry
  • Clostridioides difficile / enzymology*
  • Clostridioides difficile / metabolism
  • Clostridium Infections / diagnosis*
  • Clostridium Infections / microbiology
  • Diagnostic Tests, Routine / methods
  • Enzyme-Linked Immunosorbent Assay / methods*
  • Glutamate Dehydrogenase / analysis*
  • Glutamate Dehydrogenase / metabolism
  • Hospitals, University
  • Humans
  • Immunoassay / methods*

Substances

  • Bacterial Proteins
  • Bacterial Toxins
  • Glutamate Dehydrogenase