Evaluation of a rapid whole blood test to detect Helicobacter pylori infection in children.

Abstract

Rapid, patient near tests for detecting antibodies against Helicobacter pylori are offered for clinical use. We evaluated the BM-Test (Boehringer Mannheim, Germany; identical to the Helisal Rapid Blood Test) in children with recurrent abdominal pain. The BM-Test and 13C-urea breath test (UBT) were performed in 195 children (4-18 years). Symptoms were assessed using a 4-week diary. Upper endoscopy was performed in all UBT-positive children and in UBT-negative children with symptoms suggestive of organic disease. H. pylori status was considered positive if at least two of three methods (UBT, histology or rapid urease test) or culture were positive. After exclusion of children with previous H. pylori therapy (n = 8) and undetermined H. pylori status (n = 1), 61/186 (33%) children were H. pylori positive. The BM-Test in relation to H. pylori status revealed a sensitivity of 54%, specificity of 90%, a likelihood ratio of 5.2 for a positive, and of 0.4 for a negative test result. Accuracy of the test was independent of ethnicity, gender, age, family history for ulcer disease, frequency or severity of abdominal symptoms, epigastric tenderness, type of blood sampling (capillary versus venous) and DOB values of the UBT. In eight previously treated children, the test gave one false-positive and three false-negative results. Almost half of H. pylori-infected children and 10% of non-infected children were misclassified by the BM-Test. False-negative results are not related to young age or certain ethnic groups. The poor performance makes the test unsuitable for epidemiological and clinical use in children.