Mutational analysis of antibiotic resistance genes in Helicobacter pylori from Ghanaian dyspepsia patients: Implications for treatment strategies

Background

Antibiotic resistance jeopardizes the effectiveness of conventional treatment regimens for Helicobacter pylori infections, and this remains a major global health concern. H. pylori genes mutations negatively affect actions of most first line antibiotics. This study aimed to perform mutational analysis on H. pylori antibiotic resistance genes in Ghanaian patients diagnosed with dyspepsia.

Materials and methods

Antrum gastric biopsies were taken from 169 study participants, minced in Brain Heart Infusion broth and cultured. Sensitivity to antibiotics of H. pylori isolates was determined by disc diffusion. Extracted DNA were amplified and antibiotic resistance genes gyrA, pbp1, and rdxA sequenced. Resistance genes were analysed for base and point mutations using online databases and Ugene 45.0 software.

Results

Using rapid urease test, H. pylori infection prevalence was estimated to be 61%. Phenotypically, no sensitivity was recorded for metronidazole, amoxicillin, clarithromycin, and amoxicillin-clavulanic acid against the tested isolates. Resistance to levofloxacin was found to be 40% while 20% was recorded for each of tetracycline and ciprofloxacin. Mutations identified included G242 C/A, T254I, and S417T for pbp1 gene in amoxicillin resistance; K2N, Q6H, Q50Stop, E75K, R90K, G98S, H99P, R131K, and A183V for rdxA gene; N87I/T, A97V, M191I, V199 M/A, H200Y, and G208E for gyrA gene in levofloxacin resistance.

Conclusions

There is high H. pylori antibiotic resistance in the region with amoxicillin, metronidazole, amoxicillin-clavulanic acid and clarithromycin showing no sensitivity to tested isolates. Tetracycline and ciprofloxacin may be more appropriate therapeutic regimen options against H. pylori. Observed resistance could be due to mutations in rdxA, pbp1, and gyrA genes.