Comparative evaluation of conventional methods and Elisa based IgG antibodies detection for diagnosis of helicobacter pylori infection in cases of dyspepsia

Arora u.et al,Indian Journal of Medical Microbiology

Year : 2003  |  Volume : 21  |  Issue : 1 

INTRODUCTIONINTRODUCTION

Helicobacter pylori is a gram negative,spiral flagellated bacterium that colonizes the human stomach.

Presently, its role has been established in chronic antral gastritis, duodenal ulcer, chronic gastric ulcer, dyspepsia, gastric cancer and gastric lymphoma ..

World Health Organization added H.pylori to its list World Health Organization added H.pylori to its list of known carcinogens.of known carcinogens.

The diagnosis of H.pylori infection is currently based upon endoscopic biopsy based invasive tests (Rapid urease, culture, Gram staining and histopathology)

Non invasive, serology based tests detecting IgG antibodies (since H.pylori causes chronic infection) are commercially available.

INTRODUCTIONINTRODUCTION

INTRODUCTIONINTRODUCTION

AS invasive procedures are tedious hence every person complaining of symptoms suggestive of gastroduodenal disease cannot be subjected to these tests

The present study was therefore planned for comparative evaluation of conventional methods and ELISA based IgG antibody detection by a commercially available kit for diagnosis of H.pylori infection in cases of dyspepsia

Subjects: 75 dyspeptic patients Specimen: Gastric biopsy specimen Serum samples Tests procedures : Biopsy specimens were processed for rapid urease

test, gram staining and culture. Serum samples were used for detecting IgG antibodies

against 128kDa external protein (Cag A) of H.pylori using a commercially available ELISA kit.

Materials and MethodsMaterials and Methods

ResultsResults

Type of Test Patients ( n = 75 )

Positive Percentage

Rapid urease test : 54 72%

Gram staining 15 20%

Culture 21 28%

Significant IgG titres (20U/ml) 57 76%

The difficulties associated with invasive test and low isolation rate of this organism has led to the development of various serological test

Results of positive serology also comparable with biopsy based RUT which at present is most commonly used test for diagnosis of H.pylori infection

DiscussionDiscussion

DiscussionDiscussion

No case was detected in which rapid urease test was positive but serology insignificant.

Three cases were negative by rapid urease test, but had significant IgG levels. This may be due to……

ConclusionConclusion

We recommend serology as a screening procedure only and if the titres are insignificant, the role of endoscopy just to make a diagnosis of H.pylori infection in dyspeptic patients is not warranted.