ABSTRACT
BACKGROUND: Primary clarithromycin resistance markedly reduces Helicobacter pylori eradication rate following standard therapies. Prevalence of primary clarithromycin resistance in H. pylori is increasing, and three point mutations are mainly involved. AIM. To assess both the prevalence of primary clarithromycin resistance in Italy, and the distribution of the involved point mutations. METHODS: Primary clarithromycin resistance was assessed by TaqMan real-time polymerase chain reaction on antral biopsies of 253 consecutive, H. pylori infected patients enrolled in 13 Italian centres between January and September 2010. RESULTS: Primary clarithromycin resistance was detected in 25 (9.9%) patients, with prevalence values widely ranging from 0 to 25%. Clarithromycin resistance rate was higher in female as compared to male patients (13.4% vs. 5.3%, p=0.03), and it tended to be higher in non-ulcer dyspepsia than in peptic ulcer patients (10.6% vs. 6.9%, p=0.5), female patients with non-ulcer dyspepsia showing the highest value (15.4%). The A2143G point mutation was detected in 13 (52.0%) patients, the A2142G in 9 (34.6%), whilst a double point mutation (A2143G plus A2142G) in 3 (11.6%) cases. CONCLUSIONS: Primary clarithromycin resistance is highly variable in different Italian geographic areas. High resistance rates were observed in female and in dyspeptic patients. Among the three point mutations of clarithromycin resistance, the A2143G remains the most frequently observed.
Subject(s)
Anti-Bacterial Agents/pharmacology , Clarithromycin/pharmacology , Helicobacter pylori/drug effects , Adult , Aged , Drug Resistance, Bacterial , Female , Helicobacter Infections/drug therapy , Humans , Italy , Male , Middle AgedABSTRACT
OBJECTIVES: We sought (i) to validate a new prediction rule of mortality (Progetto Nazionale Emorragia Digestiva (PNED) score) on an independent population with non-variceal upper gastrointestinal bleeding (UGIB) and (ii) to compare the accuracy of the Italian PNED score vs. the Rockall score in predicting the risk of death. METHODS: We conducted prospective validation of analysis of consecutive patients with UGIB at 21 hospitals from 2007 to 2008. Outcome measure was 30-day mortality. All the variables used to calculate the Rockall score as well as those identified in the Italian predictive model were considered. Calibration of the model was tested using the chi2 goodness-of-fit and performance characteristics with receiver operating characteristic (ROC) analysis. The area under the ROC curve (AUC) was used to quantify the diagnostic accuracy of the two predictive models. RESULTS: Over a 16-month period, data on 1,360 patients were entered in a national database and analyzed. Peptic ulcer bleeding was recorded in 60.7% of cases. One or more comorbidities were present in 66% of patients. Endoscopic treatment was delivered in all high-risk patients followed by high-dose intravenous proton pump inhibitor in 95% of them. Sixty-six patients died (mortality 4.85%; 3.54-5.75). The PNED score showed a high discriminant capability and was significantly superior to the Rockall score in predicting the risk of death (AUC 0.81 (0.72-0.90) vs. 0.66 (0.60-0.72), P<0.000). Positive likelihood ratio for mortality in patients with a PNED risk score >8 was 16.05. CONCLUSIONS: The Italian 10-point score for the prediction of death was successfully validated in this independent population of patients with non-variceal gastrointestinal bleeding. The PNED score is accurate and superior to the Rockall score. Further external validation at the international level is needed.
