Efflux pump mediated antibiotic resistance in clinical isolates of Helicobacter pylori from South West Nigeria.

Introduction Helicobacter pylori is a spiral shaped gram negative bacterium majorly causing peptic ulcers and gastric cancer in humans. The combinations of two or more antibiotics such as amoxicillin, clarithromycin, metronidazole or tetracycline with anti-secretory agents or bismuth have been used successfully for the treatment of H. pylori . Aim Increasing antibiotic resistance has been a contributory factor to treatment failures; as such evaluation of resistance mechanism will improve the management of H. pylori infection. Methodology The antibiotic resistance in H. pylori isolates from Nigeria was determined using E-test strips from Biomerieux SA, France and PCR for the efflux pump gene detection. Results Resistance to metronidazole was found to be 93% (97/104), amoxicillin 42% (44/104), clarithromycin 39% (41/104) and tetracycline 27% (28/104). However 51% (53/104) of the isolates harboured multidrug efflux pump gene hefA (Hp605) and 34% (35/104) hefD (Hp 971). However, hefG (Hp 1327) was absent in all the isolates. There was significant association between clarithromycin resistance and hefA with p-value 0.014, there was also association between amoxicillin resistance and hefD with p-value 0.004. Conclusion The present study revealed that H. pylori antibiotic resistance is on the increase in Nigerian strains and the mechanism of resistance may possibly include the possession of multidrug efflux pump.