Decreased sensitivity of the ultrarapid urease test for diagnosing Helicobacter pylori in patients with chronic renal failure

Fifty patients with chronic renal failure and 50 asymptomatic healthy volun teers were studied to determine the prevalence of Helicobacter pylori in th e two groups and to compare the results of ultrarapid urease test (URUT) an d gastric histology for detecting H. pylori infection. Four gastric antral biopsy specimens were taken. Two specimens were used for the URUT and two w ere processed routinely. Sections were stained with H&E and Loeffler's meth ylene blue. Histological examination showed presence of H. pylori in 56% of patients with chronic renal failure (CRF) and in 78% of the controls. The difference was statistically significant (p < 0.05). The URUT was positive in only 16% of patients with CRF compared to 74% in the controls (p < 0.000 1). The sensitivity and overall diagnostic accuracy of the URUT to diagnose H. pylori infection were 94.8 and 96%, respectively, in controls but were only 29 and 60%, respectively, in patients with CRF. it is concluded that t he prevalence of H. pylori is significantly less in patients with CRF and t hat the URUT is less sensitive than gastric histology for diagnosing H. pyl ori infection in these patients.