COMPARISON AMONG DIFFERENT LABORATORY TESTS FOR THE DIAGNOSIS OF HELICOBACTER PYLORI INFECTION IN DYSPEPTIC PATIENTS IN SULAIMANI GOVERNORATE  



Aryan Fuad H. Khorshid a, Sherko A Omer b and Aras Aziz Abdulla c 


a  Sulaimani Directorate of Health 
b Department of Microbiology, College of Medicine, University of Sulaimani.
c Department of Medicine, College of Medicine, University of Sulaimani.

Submitted: 11/9/2016; Accepted: 26/3/2017

DOI Link: 

ABSTRACT


Background

Helicobacter pylori is a helical Gram-negative bacterium that colonizes human gastric mucosa leading to various pathologies including gastritis, gastric ulcers and gastric adenocarcinoma. Colonization is worldwide and affecting all age groups.

Objectives 

To identify H. pylori colonization among patients with dyspepsia using different laboratory tests including serology, stool antigen and PCR, and comparing the sensitivity and specificity of these tests.

Materials and Methods

From June through December 2014, one hundred patients with dyspepsia were enrolled in this study. They were 64 females (mean age 40.2 y) and 36 males (mean age 42.1 y). Two gastric antral biopsy specimens were taken in all patients submitted to esophagogastroduodenoscopy. Blood and stool specimens were also obtained from each patient. Four diagnostic laboratory tests were used for detection of the infection. Blood samples were tested for antibodies using rapid immunochromatography assay, stool for H. pylori antigen with immunochromatographic method and lastly PCR amplification of glmM gene was used to detect the organism in both gastric tissue and stool samples. 

Results
Esophagogastroduodenoscopy revealed that the majority of patients had gastritis and or duodenitis. Stool PCR for H. pylori was positive in 42% of the patients. Anti-H. pylori IgG in the blood and bacterial antigen were detected in 72% and 74% of patients respectively, while PCR test on gastric biopsy specimens was positive in 82% of the samples. 

Conclusion

H. pylori infection was detected regardless of the presence or absence of visible gastroduodenal pathology. PCR examination of gastric tissue was better than stool samples. In comparison to gastric biopsy PCR, stool antigen detection was found to be the most sensitive test reaching 87.8% while stool PCR was the most specific test. No single test solely can be used to diagnose or exclude colonization.

KEYWORDS

Diagnosis of H. pylori, Dyspepsia, Stool antigen, Antral biopsy, PCR.