Helicobacer pylori detection using local (in-house) rapid Urease reagent in Jos, Nigeria.
Background: Since the discovery of Helicobacter pylori (H. pylori) by Robin Warren and Barry Marshall in 1982 and its subsequent association with diseases like antral (type B) gastritis, peptic ulcer disease (PUD), gastric cancer and gastric Mucosal Associated Lymphoid Tissue (MALT) lymphoma, various invasive as well as non-invasive methods of detecting the bacterium have been developed. The choice of a particular method usually depends on availability, cost, reliability and convenience of diagnostic facility. Non-availability and high cost of commercially prepared rapid urease test kits have led to the development of locally prepared reagents to serve same purpose. This study compared a locally prepared (“in-house”) rapid urease test solution with standard culture in detecting the presence of H. pylori in gastric biopsies to determine the validity of the former. Materials and Methods: This was a prospective cross sectional study carried out over a 6 months period (April-September 2001) to determine the validity of a locality prepared rapid urease reagent in detecting H. pylori infection among dyspeptic patients at the Jos University Teaching Hospital (JUTH), Jos. Two pairs of antral gastric biopsies were obtained from patients at endoscopy and a pair each was used for rapid urease test using a locally prepared urease reagent and cultures on a horse blood agar. The results of the two methods (cultures being the standard) were analyzed using SPSS (version 11.0) statistical programme and tests of validity carried out. Results: A total of 39 patients made up of 24(61.5%) males and 15(38.5%) females in which rapid urease test were done and culture carried out were studied. The ages of the patients studied ranged from 15 to 70years with mean age of 38.4+12.08 years. 34 (87.2%) and 36 (92.3%) of the patients tested positive to H. pylori using the local rapid urease test and culture respectively. Five (1.3%) and 3 (0.8%) of the patients were negative by rapid urease and cultures respectively. The results of the local rapid urease test were then compared with that of culture. A sensitivity and specificity of 91.7% and 66.7% respectively were obtained for the local rapid urease test. The positive and negative predictive values were 94.1% and 40% respectively. Conclusion: With a sensitivity of 91.7%, the locally prepared rapid urease test is comparable to cultures in detecting H. pylori in gastric biopsy specimens. With this finding and with commercially prepared rapid urease kits either not available or expensive, and cultures cumbersome, the use of locally prepared rapid urease test reagents is appropriate, practicable and sustainable in low resource settings like ours.
Sahel Medical Journal Vol. 11 (3) 2008: pp. 93-96