Antibiotic Resistant Pattern of Helicobacter Pylori Infection Based on Molecular Tests in Laos

The efficacy of standard treatment of Helicobacter pylori (H. pylori) is declining because of antibiotic resistance. Clarithromycin resistance is also increasing in many Asian countries. The aim of this study was to determine the antibiotic susceptibility patterns of H. pylori infection and clinical association in Laos.

A total of 329 Lao dyspeptic patients who underwent gastroscopy at Mahosot Hospital, Vientiane, Laos during December 2010-March 2012 were enrolled in this study. During gastroscopy, 4 biopsies were collected (2 each from the antrum and body) for CLO-test and histopathology. Only the positive CLO-test gastric tissues was stored at -80° in a freezer until DNA was extracted and a GenoType®HelicoDR test was conducted for detecting mutations in the rrl gene encoding 23S rRNA (clarithromycin resistance) and mutations in gyrA gene (fluoroquinolone resistance) .

Of the total, 119 Lao patients (36.2%) were infected with H. pylori including 59 males (49.6%) and 60 females (50.4%) with a mean age of 46 years. Clarithromycin and fluoroquinolone resistance of H. pylori infection was demonstrated in 15 (12.6%) and 16 strains (13.4%) respectively. In clarithromycin resistance, the number of patients who had education above primary school and BMI≥ 25 kg/m2 were significantly higher than those who had education below primary school and BMI< 25 kg/m2 (23.1% vs 7.5%, P-value= 0.036 and 20.5% vs 8%, P-value= 0.048, respectively). In fluoroquinolone resistance, the number of lowland Lao was significantly higher than those of non- lowland (highland and midland) Lao ethnic groups (16.7% vs 0%, P-value= 0.039).

H. pylori infections remain common in Laos. Clarithromycin and fluoroquinolone resistance with H. pylori infection are growing problems. Education above primary school and BMI ≥ 25 kg/m2 might be predictors for clarithromycin resistance and lowland Lao ethnicity might be predictors for fluoroquinolone resistance with H. pylori infection in Laos.