Helicobacter genotyping and detection in peroperative lavage fluid in patients with perforated peptic ulcer

Certain Helicobacter pylori genotypes are associated with peptic ulcer disease; however, little is known about associations between the H. pylori genotype and perforated peptic ulcer (PPU). The primary aim of this study was to evaluate which genotypes are present in patients with PPU and which genotype is dominant in this population. The secondary aim was to study the possibility of determining the H. pylori status in a way other than by biopsy.

Serum samples, gastric tissue biopsies, lavage fluid, and fluid from the nasogastric tube were collected from patients operated upon for PPU. By means of PCR, DEIA, and LIPA the presence of the "cytotoxin associated gene" (cagA) and the genotype of the "vacuolating cytotoxin gene" were determined.

Fluid from the nasogastric tube was obtained from 25 patients, lavage fluid from 26 patients, serum samples from 20 patients and biopsies from 18 patients. Several genotypes were found, of which the vacA s1 cagA positive strains were predominant. Additionally, a correlation was found between the H. pylori presence in biopsy and its presence in lavage fluid (p=0.015), rendering the latter as an alternative for biopsy. Sensitivity and specificity of lavage fluid analysis were 100% and 67%, respectively.

This study shows the vacA s1 cagA positive strain is predominant in a PPU population. The correlation found between the H. pylori presence in biopsy and its presence in lavage fluid suggests that analysis of the lavage fluid is sufficient to determine the H. pylori presence. Risks associated with biopsy taking may be avoided.