Systematic review: Accuracy of diagnostic methods for Clostridioides difficile infection

Bianca Caroline Salvador; Diego Lima Gomes; Ariane Gonçalves Silva de Araujo; Ana Carolina Cardoso Gomes Marcelino; Carolina Rempel; Renata Szpak; Talita Antunes Antoniolli Pontes; Fernanda Stumpf Tonin; Keite da Silva Nogueira; Astrid Wiens

doi:10.1016/j.anaerobe.2026.103038

Systematic review: Accuracy of diagnostic methods for Clostridioides difficile infection

Anaerobe. 2026 Mar 14:98:103038. doi: 10.1016/j.anaerobe.2026.103038. Online ahead of print.

Affiliations

¹ Federal University of Paraná, Postgraduate Program in Pharmaceutical Sciences, Curitiba, PR, Brazil.
² Federal University of Paraná, Department of Pharmacy, Curitiba, PR, Brazil.
³ Federal University of Paraná, Postgraduate Program in Pharmaceutical Services and Policies, Curitiba, PR, Brazil.
⁴ Pharmacy and Pharmaceutical Technology Department, Social and Legal Pharmacy Section, University of Granada, Granada, Spain.
⁵ Federal University of Parana, Clinics Hospital, Bacteriology Laboratory, Curitiba, Parana, Brazil; Federal University of Parana, Department of Pathology, Curitiba, Parana, Brazil.
⁶ Federal University of Paraná, Department of Pharmacy, Curitiba, PR, Brazil. Electronic address: astrid@ufpr.br.

PMID: 41833705
DOI: 10.1016/j.anaerobe.2026.103038

Abstract

Objectives: To analyze the accuracy of diagnostic methodologies for Clostridioides difficile infection (CDI).

Methods: A systematic review was conducted in Medline, Embase, and Lilacs (July 2024). Studies with patients suspected of CDI using any diagnostic method (TC [toxigenic culture], LA [latex agglutination], CCNA [cell cytotoxicity neutralization assay], EIA [enzyme immunoassay], or NAAT [nucleic acid amplification test]) were included. Studies qualities were assessed using QUADAS-2 and QUADAS-C (Quality Assessment of Diagnostic Accuracy Studies - 2 and Comparative Accuracy), and evidence quality using GRADE (Grading of Recommendations Assessment, Development and Evaluation). Meta-analysis (MA) was performed considering central value and 95% confidence interval. This study was registered in PROSPERO (CRD42021234898) and supported by CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil).

Results: 170 studies were included, 79 entered the MA, covering at least 98,786 stool samples. Studies evaluated several methodologies, such as TC; EIA for GDH (glutamate dehydrogenase), GDH and toxin A, GDH and toxin AB, EIA for toxin A or toxin AB; molecular tests like NAAT for toxin A, toxin AB, toxin B and ribotype 027, toxin B/Bi and ribotype 027, toxin A/B/Bi and ribotype 027, toxin B and LA. TC was the most commonly used reference test (93.5%). MA showed variability among methods. Molecular biology methodologies were favored for identifying toxins A and B, with significant accuracy. EIA for GDH was an effective screening method (sensitivity: 91.599% [89.149 - 94.049]).

Conclusion: CDI detection presents challenges without defined gold standard. EIA and NAAT revolutionized diagnostics, offering high accuracy, and faster diagnosis.

Keywords: Accuracy; Clostridioides difficile; Clostridioides difficile infection; Enzyme immunoassay; Molecular tests; Nucleic acid amplification test.