Antral exfoliative cytology for the detection of Helicobacter pylori in the stomach

Table 1 Comparison of the results from the exfoliative cytology method against those obtained from the combined histology and urease test.

Exfoliative cytology	Histology and urease both positive	Histology and urease both negative
Positive	n = 28	n = 6
Negative	n = 3	n = 12

n = number of patients. Accuracy: 81.6% = (28+12/28+3+6+12); Sensitivity: 90.3% = (28/28+3); Specificity: 66.6% = (12/12+6); PPV: 82.3% = (28/28+6); NPV: 80.0% = (12/12+3); PPV: positive predictive value; NPV: negative predictive value.

Table 2 Agreement between the quantification of H pylori by the histology and exfoliative cytology methods and the time of the color change in the urease test.

Level	Kappa value (k)	Kappa value (P)
1	0.70	<0.000001
2	0.25	= 0.0009
3	0.28	= 0.0002
4	0.49	<0.000001