Impact of Clarithromycin Resistance on Eradication of Helicobacter pylori in Infected Adults

Abstract

The outcome of Helicobacter pylori infection was analyzed in 114 dyspeptic patients treated with triple-drug therapy including clarithromycin. Clarithromycin resistance (in 20.2% of our isolates) was mainly caused by an A2142G mutation in the 23S rRNA gene of H. pylori. H. pylori eradication was obtained in all patients with clarithromycin-susceptible isolates but not in any patients with clarithromycin-resistant isolates (P ‫؍‬ 0.0001). Therefore, it would be useful to conduct H. pylori antimicrobial susceptibility testing of the first gastric biopsy culture before choosing the first three drugs for therapy of infected patients.

Phenotypic and genotypic correlation as expressed in Helicobacter pylori resistance to clarithromycin and fluoroquinolones

“…A2143G mutation has a higher risk of eradication failure [15,16,21,25]. This mutation demonstrated the highest rate among examined mutations, in accordance with other studies [14,22,24].…”

“…In the current study resistance to fluoroquinolones was detected only by the molecular method GenoType HelicoDR kit, with a higher resistance rate compared to data published in Israel in 2015 [15,16]. This finding could be explained by the high sensitivity of the molecular kit, which is not routinely used, enabling detection of genotypic resistance, in accordance with a worldwide trend of a rise in fluoroquinolones resistance [14,17,18].…”

“…Our findings demonstrate that PCR is a more sensitive method (80.3% sensitivity, 75.0% specificity), with a higher H. pylori detection rate compared to culture [14][15][16][17].…”

Antimicrobial susceptibility of Helicobacter pylori and mechanisms of clarithromycin resistance in strains isolated from patients in Uruguay

“…High percentages (27%) of resistance to this drug are also reported in Japan (18). In this case, the clinical implications are significant, since a clear reduction in the response rates obtained with the classical plan has been demonstrated (19,20). With regard to fluoroquinolones, there are few resistance studies.…”

Clarithromycin-resistant Helicobacter pylori in Recife, Brazil, directly identified from gastric biopsies by polymerase chain reaction

“…This is advocated particularly for clarithromycin, the most effective drug used in the eradication of the organism, resistance to which is the main factor responsible for treatment failure (3,7,9) . Pretreatment susceptibility testing for clarithromycin is needed if the prevalence of primary resistance in the community reaches 15%-20% (8) .…”