Prevalence of Primary Resistance of <b><i>Helicobacter pylori</i></b> to Clarithromycin and Levofloxacin in Southern Spain

Abstract

Background: The eradication of Helicobacter pylori (HP) using clarithromycin (CLA)-based triple therapy depends on the resistance of HP to antibiotics. The Maastricht III conference recommends the implementation of locoregional surveillance programmes for primary resistance of HP to CLA. In Andalusia, there are no previous data in this respect. The aim of this study was to determine the prevalence of the primary resistance of HP to CLA and levofloxacin (LF) in southern Spain. Methods: Multicentre cross sectional study was carried out in 6 hospitals in Andalusia. Patients of both sexes numbering 401 were included (male 48%), aged 18-80 years and naïve to HP eradication. Resistance of HP to CLA (CLAr) and LF (LFr) was assessed by determining mutations by PCR: mutations of the 23S rRNA gene define CLAr and mutations of the gene gyrA define LFr. Four hundred one gastric samples were collected. CLAr was detected in 72 patients (17.9%) and LFr was detected in 56 patients (13.9%). Heteroresistance was detected for both antibiotics: CLA 37/72 (51.3%) and LF 28/56 (50%). Variability for CLAr was detected among the centres, ranging from 11.5% to 24.7% without statistical significance (p = 0.12). Female sex was related to CLAr. Conclusions: In Andalusia, there is a high rate of primary CLAr and LFr. CLA-based triple therapy should be avoided as the primary eradication regimen in this region. There is a wide variability in the rate of CLAr among centres.

Detection ofHelicobacter pyloriresistance to clarithromycin and fluoroquinolones in Brazil: A national survey

“…Similar results were also reported in Belgium, where multiple mutations were found in 25% of samples for fluoroquinolones and 12% for clarithromycin[19]. Finally, simultaneous resistance to both antibiotics was unusual (4.3%) in our study, similar to what was reported in South Africa (2.5%)[22], Hong Kong (3.7%)[36], Italy (1.6%)[37], and Spain (4%)[38]. …”

Helicobacter pylori pathogenicity and primary antimicrobial resistance in Northern Spain

“…18 Our LV-R isolates showed the mutation D91N and N87K in 84.6%. 3,25,26 No resistance to amoxicillin or tetracycline was observed, in line with the very low resistance rates described by other authors. These results emphasized the importance of phenotypic antimicrobial susceptibility testing prior treatment since molecular techniques available only detect the most frequent mutations associated with resistance.…”

“…[24][25][26] The main cause of fluoroquinolone resistance is mutation in the QRDR at position 87 and 91. Primary LV-R was 13.1%, much lower than the 38.7% recently reported in the northwest of Spain, 3 but in line with other Spanish studies.…”

The Need for Resistance Surveillance and Antimicrobial Susceptibility Testing of Helicobacter pylori

“…Antimicrobial resistances to H. pylori , however, are increasing worldwide and hinder the success of such empirical treatments. The work by Narravo-Jarabo et al [2] , published in the last issue of Digestion, shows that in the Spanish region of Andalusia, primary resistances to clarithromycin and levofloxacin may vary considerably from individual to individual. Their multicenter study revealed that primary resistance to the key antibiotic -clarithromycin -was ranging from 11 to 25%, primary resistance to levofloxacin was ranging from 7 to 17%.…”

“…Continuous surveillance studies that monitor the present state of antimicrobial resistance are indispensable to establish updated guidelines on first-line eradication treatments. Remarkably, Narravo-Jarabo et al [2] tested the resistance to clarithromycin and levofloxacin at the molecular genetic level by identification of mutations conferring resistance. International guidelines recommend susceptibility testing after a second failure of empirical treatments [1].…”