Mucosal polymerase chain reaction for diagnosing Helicobacter pylori infection in patients with bleeding peptic ulcers

Table 3 Results of PCR test in patients with chronic gastritis, non-bleeding and bleeding peptic ulcers (PU).

Patients	PCR results	Hp (+)	Hp (-)	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	Accuracy (%)
Chronic gastritis	Positive	20	0	100	100	100	100	100
	Negative	0	17	(99.9-100.1)	(99.9-100.1)	(99.9-100.1)	(99.9-100.1)	(99.9-100.1)
Non-bleeding	PU Positive	70	1	99	90	99	90	98
	Negative	1	9	(98.9-99.1)	(89.9-90.1)	(98.9-99.1)	(89.9-90.1)	(97.9-98.1)
Bleeding PU	Positive	38	10	84b	77	79d	83a	81f
	Negative	7	33	(83.9-84.1)	(76.9-77.1)	(78.9-79.1)	(82.9-83.1)	(80.9-81.1)

^bP<0.001 vs non-bleeding, P = 0.02 vs chronic gastritis;

^dP<0.01 vs non-bleeding;

^fP = 0.001 vs chronic gastritis, P<0.001 vs non-bleeding;

^aP=0.02 vs chronic gastritis. Hp+: either positive H pylori culture or both positive rapid urease test and histology. PPV: positive predictive value, NPV: negative predictive value.