Real-Time PCR detection and quantitation of clarithromycin-resistant strains in archival material and correlation with Sydney classification.

Background: , infects gastric mucosa causing gastritis. Treatment failure is mainly due to certain genetic changes in the peptidyltransferase loop of 23S rRNA of the microorganism. The aim of the study was to evaluate genetic changes in gastric biopsies of (+) patients that lead to clarithromycin resistance and to correlate them with histology data.