Table 6.2-2. Characteristics of laboratory tests used in the diagnosis of Clostridium (Clostridioides) difficile infection

Test

Target

Sensitivity

Specificity

NPV

PPV

Turnaround time

EIA

Toxins A + B

60%

98%

 Low

High

20-90 min

GDH

Common antigen

90%

50%

High

Low

20-90 min

NAAT (PCR, LAMP)

Toxin B gene

90%

65%

High

Low

90-200 min

GDH, glutamate dehydrogenase; LAMP, loop-mediated isothermal amplification; NAAT, nucleic acid amplification test; NPV, negative predictive value; PCR, polymerase chain reaction; PPV, positive predictive value.