Accuracy of serology for the diagnosis of Helicobacter pylori infection--a comparison of eight kits.

Abstract

Aims-To determine the accuracy of eight commercially available kits for the serological diagnosis of Helicobacterpylori infection, and hence whether a serology service could be introduced to reduce endoscopy workload. Methods-Eighty four patients newly presenting to their general practitioners with dyspepsia were recruited. Gold standard diagnosis of H pylori infection was obtained both by a histological examination of gastroduodenal biopsy specimens and by the "C-urea breath test (UBT). The performance of six quantitative and two qualitative enzyme linked immunosorbent assays for H pylori IgG, used according to the manufacturers' instructions, with serum samples obtained during the endoscopy visit, were compared. Results-The study population had a median age of 45 years, and the prevalence of H pyloni infection was 35%. With one exception, where the patient had received a course of anti-H pylori treatment between endoscopy and UBT, there was 100% concordance in the results of the two gold standard techniques. Discordant serology results were more common in patients aged >50 years (42% of the total) than in younger patients (21%), and this was most noticeable in uninfected patients. The sensitivity of the kits was good (90-100%), but specificity was more variable (76-96%), and the rate of equivocal results was unacceptably high in some cases (0-12%). The overall accuracy of the kits ranged from 83 to 98%. Two kits in particular performed well (Pylori-Elisa II, BioWhitaker and Premier, Launch; qualitative) with 98% and 100% accuracy, respectively. Conclusions-In a symptomatic population with a prevalence of H pyloni infection of 35%, particularly in patients aged <50 years, some but not all serology kits may be used as a highly accurate and inexpensive alternative to the gold standard techniques.

Cutoff Serum Pepsinogen Values for Predicting Gastric Acid Secretion Status

“…Secondly, Since H. pylori status was determined by serum antibody test alone in the present study, some misclassification could occur in the present study. However, IgG antibody test showed high sensitivity and specificity over 90% for diagnosing H. pylori infection (Wilcox et al 1996;Sasazuki et al 2006) and it would be practical in clinical settings to measure both H. pylori antibody and pepsinogen concentrations using the same serum samples. Finally, the PG cutoff values calculated in the present analysis could not be applied to those with a history of H. pylori eradication because the correlation between gastric acid secretion and serum PGs is considerably altered after the therapy (Iijima et al 2009b).…”

Diagnostic accuracy of serological kits for Helicobacter pylori infection with the same assay system but different antigens in a Japanese patient population

“…Many ELISA kits for detection of H. pylori antibodies are available and have reportedly provided highly reliable results in Western countries (Evans et al, 1989;Crabtree et al, 1991;Jensen et al, 1993;Schembri et al, 1993;Marchildon et al, 1996;Wilcox et al, 1996;Meijer et al, 1997;Leung et al, 1999;Raymond et al, 1999). However, diagnostic accuracy of kits made in Western countries has been reported to be lower in Chinese patients (Leung et al, 1999).…”

Investigation of Helicobacter pylori in Laryngeal Papillomatosis

“…The quality of culture medium and delivery condition are effective on the outcome of in vitro culture. Whereas false negative result can be seen in UBT experiment because of the treatment by antiacid, bismut and antibiotic (32). Serological methods which are not expensive because of doubting accuracy are limited.…”