Apparent Intracellular Helicobacter pylori Detected by Immunohistochemistry: The Missing Link in Eradication Failure. (22nd June 2020)

• Record Type: Journal Article
• Authors: Beer, Andrea; Hudler, Helmut; Hader, Maria; Kundi, Michael; Hudler, Susanne; Täuber, Valentina; Schachner, Helga; Gruber, Sophie; Hirschl, Alexander M; Kain, Renate; Makristathis, Athanasios
• Is Part Of: Clinical infectious diseases. Volume 73:Number 7(2021)
• Page Start: e1719
• Page End: e1726
• Publication Date: 2020-06-22
• Subjects: Helicobacter pylori -- immunohistochemistry -- apparent intracellular occurrence -- eradication failure; Communicable diseases -- Periodicals; 616.905
• DOI: 10.1093/cid/ciaa839
• Languages: English
• ISSNs: 1058-4838

Abstract

Abstract: Background: Helicobacter pylori is primarily an extracellularly living bacterium. However, seemingly intracellular occurrence can often be detected by immunohistochemical stains. Considering antimicrobial resistance, we investigated the impact of the apparent intracellular H. pylori (aiHp) on treatment failure of first-line triple therapies. Methods: Gastric biopsies of 814 patients infected with H. pylori naive to treatment were analyzed before and after eradication therapy by immunohistochemistry. Of these, 373 received treatment consisting of amoxicillin, clarithromycin, and proton pump inhibitor (AC/PPI). Availability of polymerase chain reaction-based clarithromycin susceptibility test results from pretreatment gastric biopsies was a precondition for matching 52 aiHp to 52 non-aiHp cases within the AC/PPI group. Results: AiHp were detected mostly in low counts predominantly in corpus biopsies, rarely in antrum biopsies (95.2% vs 24.6%); they were found in 497 (61%) of all patients and in 192 of 373 patients (51.5%) in the AC/PPI group. The eradication rate in aiHp versus non-aiHp cases was 44.4% versus 72.9% in the entire sample and 45.3% versus 66.8% in the AC/PPI group. Among the 104 paired patients, respective values were 46.2% versus 78.8%; in clarithromycin-susceptible cases, 60.6% versus 91.9%. Both aiHp and resistance to clarithromycin proved to be highly significant ( P ≤ .001) and independent predictors of eradication failure. Twelve of 13 aiHp cases with a clarithromycin-sensitive strain who failed eradication developed resistance to the antibiotic. Conclusions: AiHp found by immunohistochemical staining especially in corpus biopsies proved to be a risk factor for failure of first-line triple therapies; occurrence of aiHp should be considered with regard to therapy options. Abstract : Immunohistochemical detection of seemingly intracellular Helicobacter pylori, mostly found in low counts in the deep glands of corpus biopsies, proved to be an independent risk factor for treatment failure. Their presence was associated with post-treatment development of resistance to clarithromycin.