PROSPECTIVE, MULTIVARIATE EVALUATION OF CLOTEST PERFORMANCE

Objectives: To determine prospectively the effect of aspirin, nonstero idal anti-inflammatory drugs, H2-receptor antagonists, proton pump inh ibitors, alcohol intake, race, age, history of Helicobacter pylori era dication attempts, and gastric biopsy location on CLOtest performance. Methods: Biopsy specimens were obtained from the antrum, greater curv e, and proximal stomach. One biopsy specimen from each site (except fo r the proximal stomach) was used for the CLOtest and two or more speci mens were used for histopathology. Giemsa staining was used for the de finitive determination of H. pylori status. Results: One hundred seven teen patients were included in the study, and 50 of these were infecte d with H. pylori. The sensitivity and specificity of an antral CLOtest , based on the results of Giemsa-stained sections from the antrum alon e, were 72.7 and 98.6%, respectively, whereas they were 66.0 and 100% when based on the results of Giemsa-stained sections from all three ga stric biopsy sites. The sensitivity and specificity of a body CLOtest, based on the results of Giemsa-stained sections from the body alone, were 80.5% and 93.4%, whereas they were 76.0% and 100% when based on t he results of Giemsa-stained sections from all three gastric biopsy si tes. Combining CLOtest results from the antrum and body increased CLOt est sensitivity to 82.0%. Univariate analysis revealed only one factor significantly associated with CLOtest concordance: absence of alcohol consumption (p < 0.02). Stepwise logistic regression demonstrated tha t absence of alcohol use again was independently associated with the c oncordance between overall CLOtest and all Giemsa-stained biopsy speci men results (p < 0.03) as well as between body CLOtest and body Giemsa -stained biopsy specimen results (p < 0.03). Additional independent an d significant associations were noted between antral CLOtest-antral Gi emsastained biopsy specimen results and no history of H. pylori eradic ation attempts (p = 0.04) and between body CLOtest-body Giemsa-stained biopsy specimen results and race (African-American) (p < 0.03). Concl usions: Obtaining a gastric biopsy specimen from the antrum as well as from the body increased CLOtest detection of H. pylori. CLOtest perfo rmance was shown to be affected by several demographic and clinical fa ctors.