Table 1.

Strengths and Weakness of C. difficile Tests [3, 7]

Test	Strengths	Weaknesses	Sensitivity	Specificity	Positive Predictive Value	Negative Predictive Value
Cell culture cytotoxicity neutralization assay	Detects presence of toxin	Poor sensitivity Prolonged turnaround time	65–90%	96–100%	50–87%	97–99%
Toxigenic Culture	Commonly considered the gold standard in method comparison	Detects toxin gene Prolonged turnaround time	80–100%	93–97%	57–91%	87–97%
Enzyme-linked immunosorbent assay	Detects presence of toxin Low cost Fast turnaround time	Variable sensitivity	40–100%	84–100%	50–100%	78–99%
Glutamate Dehydrogenase	Detects presence of antigen	Produced by both toxigenic and nontoxigenic strains	87–100%	76–98%	71–91%	97–100%
Nucleic acid amplification test	Detects presence of gene	Concern for overdiagnosis and detection of C. difficile colonization	83–100%	87–98%	46–94%	96–100%