Is Clostridioides difficile toxins detection necessary when the glutamate dehydrogenase enzyme is detected?

Gac Med Mex. 2021;157(1):107-109. doi: 10.24875/GMM.M21000508.

Abstract
in English, Spanish

Introduction: Clostridioides difficile causes diarrhea and pseudomembranous colitis. Its diagnosis is made with glutamate dehydrogenase (GDH) or toxins A and B detection and is confirmed with nucleic acid amplification tests.

Objective: To define if GDH determination is redundant to that of toxins.

Methods: Retrospective, observational study in diarrheal stools of patients with suspected Clostridioides difficile infection. Toxins and GDH were determined by immunochromatography. Bayesian simulation was performed with likelihood ratios; a p-value < 0.05 was regarded as significant.

Results: 329 GDH and toxin A and B results were analyzed. Clostridioides difficile infection prevalence was 18.2 %. Sensitivity and specificity of the GDH test were 0.90 and 0.89, respectively. Positive likelihood ratio was 8.9, and negative was 0.11.

Conclusions: A negative GDH result considerably reduces the probability of infection but does not rule it out. Clostridioides difficile toxins detection may be necessary in institutions where nucleic acid amplification is not affordable or accessible.

Introducción: Clostridioides difficile causa diarrea y colitis pseudomembranosa. Su diagnóstico se realiza con la detección de glutamato-deshidrogenasa (GDH) o las toxinas A y B y se confirma con pruebas de amplificación de ácidos nucleicos.

Objetivo: Definir si la determinación de GDH es redundante a la de las toxinas.

Métodos: Estudio observacional retrospectivo de muestras fecales de pacientes con sospecha de infección por Clostridioides difficile. Las toxinas y GDH se determinaron mediante inmunocromatografía. Se realizó una simulación bayesiana con los cocientes de probabilidad; se consideró significativo un valor de p < 0.05.

Resultados: Se analizaron 329 resultados de GDH y toxinas A y B. Se encontró una prevalencia de infección de Clostridioides difficile de 18.2 %. La sensibilidad y especificidad de la prueba de GDH fue de 0.90 y 0.89, respectivamente. El cociente de probabilidad positivo fue de 8.9 y el negativo, de 0.11.

Conclusiones: Un resultado negativo de GDH disminuye considerablemente la probabilidad de infección, pero no la descarta. La detección de toxinas de Clostridioides difficile puede ser necesaria en instituciones donde la amplificación de ácidos nucleicos no es económica o accesible.

Keywords: Clostridioides difficile; Glutamate dehydrogenase; Glutamato deshidrogenasa; Toxin A; Toxin B; Toxina A; Toxina B.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Aged
  • Bacterial Proteins / analysis*
  • Bacterial Toxins / analysis*
  • Bayes Theorem
  • Biomarkers / analysis
  • Clostridioides difficile*
  • Clostridium Infections / diagnosis*
  • Clostridium Infections / epidemiology
  • Diarrhea / microbiology
  • Enterotoxins / analysis*
  • Feces / chemistry*
  • Feces / enzymology
  • Female
  • Glutamate Dehydrogenase / analysis*
  • Humans
  • Likelihood Functions
  • Male
  • Middle Aged
  • Prevalence
  • Retrospective Studies
  • Sensitivity and Specificity

Substances

  • Bacterial Proteins
  • Bacterial Toxins
  • Biomarkers
  • Enterotoxins
  • tcdA protein, Clostridium difficile
  • toxB protein, Clostridium difficile
  • Glutamate Dehydrogenase