A Multiplex-Urease PCR Assay for Detection of Helicobacter pylori Infection Directly from Gastric Biopsy Specimens and Comparison of Multiplex- Urease PCR Results with Rapid Urease Test and Histopathology

Abstract

Purpose: To develop a multiplex-urease PCR assay specific for ureA and ureB genes directly from gastric biopsy specimens and compare the results of multiplex-urease PCR assay with rapid urease test (RUT) and histopathology. Methodology: This study was conducted on 109 patients. A RUT was run; histopathological staining and multiplex urease PCR were applied to biopsy specimen to detect H. pylori. Multiplex-urease PCR, RUT and histopathology results were compared by calculating Cohen’s kappa coefficient. Results: A multiplex-urease PCR assay specific for ureA and ureB genes was developed to detect H. pylori directly from biopsy specimens. Cohen's kappa coefficient results of histopathological staining and multiplex-urease PCR indicate a substantial agreement. There was a moderate agreement between the results of histopathological staining and RUT results. There is a fair agreement between the multiplex urease PCR and the RUT results. Furthermore, the multiplex-urease PCR can detect H. pylori in some samples that are identified as negative by the rapid urease test and histopathological staining method. Moreover, in some patient samples ureA could not be detected while ureB detected. Conclusion: Multiplex-urease PCR assay was developed to detect ureA and ureB genes of H. pylori directly from gastric biopsy specimens. Comparison results indicated that detection rate of H. pylori with multiplex-urease PCR and histopathological staining is higher than the RUT. Moreover, it is critical to apply RUT test to biopsy specimens taken from both antrum and corpus part as in multiplex urease PCR assay. Furthermore, developing a multiplex PCR for both ureA and ureB is essential to detect active H. pylori infection.