A simple multiplex PCR assay for diagnosing virulent Helicobacter pylori infection in human gastric biopsy specimens from subjects with gastric carcinoma and other gastro-duodenal diseases.
OBJECTIVE
To evaluate and develop a multiplex polymerase chain reaction (PCR) assay for diagnosing and specific identification of virulent Helicobacter pylori strains and their main virulence genes cagA, cagE, cagT, vacA and hrgA.


RESULTS
Genomic DNA from 82 gastric tissues was screened. A master pool of all the ingredients of multiplex reaction was prepared for amplification. Amplicons were sequenced to confirm the amplification of each target genes. Multiplex PCR assay was able to detect all the five target genes in 81.7% and deletions in one or more loci among 18.3%. Genotype cagT +ve/hrgA +ve/cagA +ve/cagE +ve/vacAs1 +ve was more predominant in this study population (67.07%). hrgA, cagT, cagE and cagA genes were present in 100%, 92.7%, 85.4% and 81.7% of the subjects, respectively. The vacAs1 subtype had higher prevalence frequency in patients with overt gastrointestinal disease (78.57%) than with GERD (gastro-esophageal reflux disease) and NUD (non-ulcer dispepsia) (50%).


CONCLUSIONS
The multiplex PCR assay developed herein was able to genotype H. pylori isolates based on the main virulence genes.


CONCLUSIONS
The ability to identify H. pylori and the majority of their virulence gene markers by multiplex PCR assay represents a considerable advancement over other PCR-based methods for genotyping H. pylori from large population, and can be explored to gain insights at the genotypic variability exhibited by this pathogen.
Tiwari
S K
SK
Center for Liver Research and Diagnostics, Deccan College of Medical Sciences, Kanchanbagh, Hyderabad, Andhra Pradesh, India.
Khan
A A
AA
Manoj
G
G
Ahmed
S
S
Abid
Z
Z
Habeeb
A
A
Habibullah
C M
CM
D000328:Adult; D001706:Biopsy; D016009:Chi-Square Distribution; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis*; D005260:Female; D005753:Gastric Mucosa / Q000382:microbiology*; D005756:Gastritis / Q000382:microbiology; D005767:Gastrointestinal Diseases / Q000382:microbiology*; D005838:Genotype; D016481:Helicobacter Infections / Q000150:complications / Q000175:diagnosis* / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000382:microbiology; D016133:Polymerase Chain Reaction / Q000379:methods; D013274:Stomach Neoplasms / Q000382:microbiology
D017931:DNA Primers; D004269:DNA, Bacterial