Assessment of the usefulness of endoscopic signs in Helicobacter pylori associated gastritis.

OBJECTIVE

To determine whether endoscopic signs exist to establish the presence of Helicobacter pylori, which may be used markers of infection in the absence of gastroduodenal peptic lesions.

METHODS

A prospective study was carried out in 150 consecutive patients, all symptomatic, who presented endoscopic evidence of gastritis and in whom the absence or presence of H. pylori was undetermined at the time of the study. A quantitative assessment was made of the three types of lesions previously associated with the presence of H. pylori on endoscopy: nodules, erosions, and red patches in the antrum. Biopsy samples were taken for the microbiological and histological studies; a positive result in either study was considered to indicate infection by H. pylori.

RESULTS

Of the 150 patients studied, 115 (76%) presented H. pylori infection. No significant differences existed with respect to the clinical findings or the distribution according to sex. The mean age of infected patients was 49 years, being lower in the nodular group (p = 0.008) and higher in the group presenting erosions (p < 0.05); this fact suggests that the endoscopic findings may differ depending on the moment of infection. Evidence of antral nodules was observed in 15 patients, 11 of whom (73%) showed positively for H. pylori; the sensitivity was 9.5% and the positive predictive value was 0.73. Of the 17 patients presenting erosions, 16 were positive for H. pylori (93.8%); the sensitivity was 13% and the positive predictive value was 0.94. Red patches were detected in 63 patients, 48 of whom (76%) were positive for H. pylori; the sensitivity was 48% and the positive predictive value was 0.76. These three patterns did not coincide in any of the patients, for an overall sensitivity and specificity of 70.5% and 80.6%, respectively (p < 0.05).

CONCLUSION

The sensitivity and specificity of the set of lesions assessed were high as no two overlapped; when the lesions were dealt with individually, however, the sensitivity was low, showing a low negative predictive value, making it necessary the use of standard detection measures, although in the presence of nodules and/ or erosions the existence of H. pylori infection is practically the norm.