Evaluation of endoscopy-based diagnostic methods for the detection of Helicobacter pylori.

BACKGROUND

Helicobacter pylori is an etiological factor in duodenal ulcer. Few studies have objectively assessed the accuracy of diagnostic methods for the detection of H. pylori.

METHODS

The sensitivity and specificity of histology, touch smear, rapid urease test (RUT) and brush cytology of endoscopic antral biopsy from patients with duodenal ulcer were compared. Forty-nine patients were evaluated before, and 34 after, eradication therapy. Each time, sampling was done for all 4 tests. The infection status for each sample was established by a positive concordance of results of three of four tests.

RESULTS

The highest degree of agreement was between RUT and cytology (kappa = 0.69). Brush cytology (100%) followed by RUT (94.5%) were the most sensitive tests. Histology had the highest specificity (89.3%). A combination of RUT or brush cytology with histology had the maximum chance of detecting H. pylori. As single tests, brush cytology and touch smear had high diagnostic accuracies with a Youdin J value of 1.79 and 1.78, respectively.

CONCLUSION

The best method for diagnosis of H. pylori is a combination of the rapid urease test or brush cytology with histology. Brush cytology or touch smear are diagnostic tests of choice if a single test is desired.