PROSPECTIVE COMPARISON OF H-AND-E, GIEMSA, AND GENTA STAINS FOR THE DIAGNOSIS OF HELICOBACTER-PYLORI

Background: H. pylori is more easily visualized with special stains th an with H&E, but this adds time and expense to the diagnostic workup. We sought to determine if the diagnostic accuracy was improved with sp ecial stains. Methods: One hundred-one patients had two ''jumbo'' biop sies taken from the gastric antrum and two from the body for examinati on with H&E, Genta, and Giemsa stains. Four separate biopsy specimens were also taken from the antrum and the body for culture and for three types of rapid urease test, and C-13- urea breath tests were also per formed. Mixed, coded biopsies were assessed for H. pylori, and density was scored from 0 to 4. A case was considered positive for H. pylori if culture was positive, two rapid urease tests and a urea breath test were positive, or two different stains were positive. Biopsy specimen s were excluded from analysis if the slides were missing or there was inadequate tissue for review, or if the specimen showed a lack of stai ning. Results: Fifty-two (13%) of 404 specimens were excluded because of a poor Genta stain. Sensitivities were comparable for the three sta ins (H&E, 92%; Giemsa, 88%; Genta, 91%), while H&E specificity (89%) w as significantly lower than that of the special stains (98%). Sensitiv ity for all three stains was significantly lower at low (grade 0 to 1) H. pylori density than at high (grade 2 to 4) density (H&E, 70% vs 98 %; Giemsa, 64% vs 96%; Genta, 66% vs 97%), and 20 of 22 false positive s were grade 1. Conclusions: The sensitivities of H&E and special stai ns are comparable at around 90%, but the specificity of H&E is signifi cantly lower. The Giemsa stain appears to be the preferred stain for H . pylori diagnosis on the basis of its goad sensitivity, excellent spe cificity, and lack of technical difficulty in preparation. However, H& E provides excellent accuracy when more than minimal (grade 1) H. pylo ri density is present.