A group of prestigious microbiologists in collaboration with endoscopy units in UK have tackled the hot topic on how to deal with the increasing Helicobacter pylori antibiotic resistance and the challenge to H. pylori eradication therapies. Standard proton pump inhibitor (PPI) triple therapy faces a dramatic drop in efficacy. The primary reason for this is clarithromycin resistance, which, until now, has been the most efficient individual component of triple therapies.
The questions addressed in the study are whether resistance surveillance is needed and on how it can be delivered. H. pylori isolates obtained from endoscopy wards in two cities in UK and from the national H. pylori reference centre provided the authors with large samples to investigate H. pylori prevalence in a symptomatic patient population as well as the current resistance pattern in the UK. The positive culture in only 6.4% of 2603 patients is strikingly low, and not representative for Europe. In search of explanation for such low prevalence of H. pylori in adult symptomatic patients, one is certainly the method selected. Culture is absolutely specific, but its sensitivity is limited due to several interfering factors.[3, 4] Another reason for the low prevalence is likely to be attributable to the fact that only antral biopsies were obtained for culture and no reference was made to PPI intake. It is known that clearance of H. pylori occurs in the antrum in around 20% of patients on PPI treatment. This is particularly relevant and accurate history of medication intake in general is limited due to the retrospective character of the study.
The prevalence of H. pylori in the adult population in Europe according to recently published data based on serology (which is not affected by intake of specific medications) is in the range of 20–60%. The reported resistance rate for clarithromycin is high, but was different between Bangor and Gloucester, and even so for levofloxacin, a second-line option in for H. pylori eradication therapy. Information as to the variation in the consumption of antibiotics in the two areas would be of interest. The high resistance rate from HRU is obvious, as it was obtained from isolates of patients with previous treatment failure.
We would like to challenge the conclusions with implications for strategies to be adopted from this study.
- Prevalence of H. pylori is still highly variable in different regions in Europe and therefore strategies of resistance surveillance need to consider the background prevalence of H. pylori.
- The recommendation of a careful history of previous antibiotic treatment is difficult in clinical practice and not sufficient to select the treatment regimen. Population surveillance will remain the key and first-line therapies should respect the local clarithromycin resistance. In the Maastricht/Florence IV report, therapies are proposed according to the local clarithromycin resistance and individual testing becomes critically important when second-line therapies fail and this is particularly relevant if chinolones are included. Quadruple therapy was shown to overcome clarithromycin resistance and moved to first-line in areas of high clarithromycin resistance.