Evaluation of Multiplex PCR with Enhanced Spore Germination for Detection of Clostridium difficile from Stool Samples of the Hospitalized Patients

Table 2

Evaluation of pretreatment and enrichment conditions prior to multiplex PCR and bacterial cell culture for the detection of C. difficile directly from stool samples.

Pretreatment condition	Enrichment condition	Incubation time (h)	Typical C. difficile colony		Multiplex PCR toxin genes detection
			CCFA agar plate	BHI agar plate
Alcohol shock	BHIS/TA	0	−	−	−
		1	−	−	+
		2	−	ND	+
		3	+	ND	+
	BHIS/TA/CC	0	−	−	−
		1	−	−	+
		2	−	ND	+
		3	+	ND	+
No alcohol shock	BHIS/TA	0	−	ND	−
		1	−/+	ND	+
		2	+	ND	+
		3	+	ND	+
	BHIS/TA/CC	0	−	ND	−
		1	−/+	ND	+
		2	+	ND	+
		3	+	ND	+

ND stands for “not determined” because there were too many contaminated bacterial species, rendering it impossible to distinguish C. difficile colonies on the plates. −/+ indicates that typical C. difficile colonies could not be observed in at least one of the three replicates.