Impact of simultaneous glutamate dehydrogenase and toxin A/B rapid immunoassay on Clostridium difficile diagnosis and treatment in hospitalized patients with antibiotic‐associated diarrhea in a university hospital of Brazil

Abstract

Glutamate dehydrogenase test is a reliable method for the diagnosis of CDI and greatly increases the number of properly treated patients with CDI. Therefore, this exam should be considered the mainstay for the laboratory diagnosis of CDI in developing countries.

Immunochromatographic test and ELISA for the detection of glutamate dehydrogenase (GDH) and A/B toxins as an alternative for the diagnosis of Clostridioides (Clostridium) difficile–associated diarrhea in foals and neonatal piglets

“…The following tests were performed on all the samples: TC, lateral flow test (immunochromatographic test) for the simultaneous detection of GDH and A/B toxins (Ecodiagnostica, Brazil), and an enzyme-linked immunosorbent assay (ELISA) kit for detecting A/B toxins (C. difficile Tox A/B II, Techlab Inc., USA). Toxigenic cultures were performed as per previously published protocols [10]: equal volumes of stool samples and 96% ethanol (v/v) were mixed and incubated for 30 min at room temperature. Subsequently, 20 μl was streaked out on cycloserine-cefoxitin fructose agar supplemented with 7% horse blood and 0.1% sodium taurocholate (Sigma-Aldrich Co., USA) [11].…”

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

“…A total of 89 adult patients (aged over 18 years), who had received antimicrobials in the last 3 months and presented diarrhea symptoms for a minimum of 72 h during hospitalization, were included in the study [3]. Similar to previous studies [7,9], diarrhea was defined as three or more discharges of loose stools a day corresponding to Bristol stool chart types 5 to 7 (as defined by Lewis et al [10]), for more than 48 h. Unformed stool samples were obtained in sterile containers and aliquots were stored at − 20°C until all tests were performed. All procedures were approved by the Research Ethics Committee of the Faculty of Medicine of the Federal University of Minas Gerais (CAAE -0710.0.203.0000.11).…”

“…All fecal samples were subjected to the following tests: two lateral flow tests (immunochromatographic tests), both of which simultaneously detect GDH and A/B toxins (Toxin/ GDH ECO Teste, Ecodiagnostica, Brazil, and C. DIFF QUIK CHEK COMPLETE, Techlab Inc., USA), an enzyme-linked immunosorbent assay (ELISA) kit for detecting A/B toxins (C. DIFFICILE TOX A/B II, Techlab Inc., USA), and toxigenic culture (TC) as the reference method. TC was performed as previously reported [7]. Briefly, equal volumes of stool samples and 96% ethanol (v/v) were mixed and incubated for 30 min at room temperature.…”

“…Recently, Cançado et al [7] showed that, in hospitals where only one method is used for the diagnosis of CDI, the replacement of ELISA assays by GDH detection considerably increases the number of patients with CDI that are correctly treated, directly affecting the control of the disease. In fact, this is the case in most Brazilian hospitals where the diagnosis of CDI is still based only on the detection of A/B toxins by ELISA [6,7]. It is also important to note that, compared with other known high-sensitivity methods, including TC and nucleic acid amplification tests, rapid tests for GDH detection are an easy-to-perform method, dispensing with the need for highly trained staff.…”

“…It is also important to note that, compared with other known high-sensitivity methods, including TC and nucleic acid amplification tests, rapid tests for GDH detection are an easy-to-perform method, dispensing with the need for highly trained staff. It is also faster than toxigenic culture, which requires between 2 and 5 days for its results and is also at least five times cheaper than molecular assays [4,5,7].…”