Alimentary tractPrimary and secondary antibiotic resistance of Helicobacter pylori strains isolated in central Italy during the years 1998–2002
Introduction
As more than 50% of the world’s population is supposedly infected by Helicobacter pylori, this may therefore be considered the most common chronic bacterial infection in humans [1]. Eradication treatment usually consists of a proton pump inhibitor (PPI) together with two of the following antibiotics: clarithromycin, a nitroimidazole derivative (metronidazole or tinidazole) and amoxycillin [2]. Resistance of H. pylori to some of the antibiotics included in the therapeutic regimens has been reported as a major reason for treatment failure [3], [4], [5]. It has been shown that, in Europe, antimicrobial primary resistance has been increasing in recent years, ranging from 10 to 50% for metronidazole and from 0 to 15% for clarithromycin, with wide variability from region to region [6], [7]. Amoxycillin-resistant human isolates of H. pylori are quite rare and have recently been identified in Italy, the USA and Canada [8], [9]. Resistance to metronidazole and/or clarithromycin after treatment failure (secondary resistance) is still much higher: 40–70% for metronidazole, 50–70% for clarithromycin, 30–90% for both metronidazole and clarithromycin [10], [11], [12], [13]. In Italy, the information on general H. pylori resistance is rather scarce, with few studies published in the scientific literature on this topic [11], [14], [15], [16].
Therefore, the aim of this study has been to determine the frequency of primary and secondary resistance to tinidazole, clarithromycin and amoxycillin in H. pylori isolates from an urban population of dyspeptic patients in central Italy and to evaluate the modification of antibiotic resistance over four consecutive 12-month periods from March 1998 to June 2002.
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Patients
From March 1998 to June 2002, 502 H. pylori-positive patients with dyspeptic symptoms undergoing endoscopy in our Unit in Pescara, a city in central Italy, were included. Four hundred and six patients (206 females, range 18–87 years, mean age 52.5 years; 200 males, range 22–86 years, mean age 54 years) had not received previous H. pylori treatment; and 96 patients (59 females, range 28–86 years, mean age 57 years; 37 males, range 34–81 years, mean age 57.5 years) had been treated previously for
Results
A total of 502 patients who satisfied the inclusion and exclusion criteria were included in the present study. Endoscopic evaluation of the patients revealed 391 subjects with gastritis, 48 with duodenal ulcer, five with gastric ulcer, two with gastric and duodenal ulcers and 56 with no gastric alteration.
Table 1 shows the prevalence of primary resistance of 406 H. pylori strains to clarithromycin, tinidazole and amoxycillin according to the period of isolation. Overall antibiotic resistance
Discussion
This is the first large study investigating the incidence of H. pylori antibiotic resistance in dyspeptic patients in central Italy. The study shows that: (a) in our geographic area there is high prevalence of H. pylori primary resistance to tinidazole, clarithromycin and both antibiotics; (b) primary resistance to clarithromycin and both clarithromycin and tinidazole is more frequent in females but is not linked to age; (c) secondary resistance is characterized by high incidence of resistance
Conflict of interest statement
None declared.
References (27)
Antibiotic resistance in Helicobacter pylori: implications for therapy
Gastroenterology
(1998)Epidemiology and mechanism of antibiotic resistance in Helicobacter pylori
Gastroenterology
(1998)- et al.
Incidence of secondary Helicobacter pylori resistance to antibiotics in treatment failures after 1-week proton pump inhibitor-based triple therapies: a prospective study
Dig Liver Dis
(2000) - et al.
Prevalence of Helicobacter pylori resistance to antibiotics in Northeast Italy: a multicentre study
Dig Liver Dis
(2000) - et al.
Characteristics and trends in macrolide resistance among Helicobacter pylori strains isolated in Bulgaria over 4 years
Diagn Microbiol Infect Dis
(1999) - et al.
Variation in antibiotic use in the European Union
Lancet
(2001) - et al.
Helicobacter pylori
Clin Microbiol Rev
(1997) Current European concepts in the management of Helicobacter pylori infection. The Maastricht Consensus Report
Gut
(1997)- et al.
Therapy and drug resistance in Helicobacter pylori infection
Dig Liver Dis
(2000) Antibiotic resistance in Helicobacter pylori infection
Br Med Bull
(1998)
Prevalence of Helicobacter pylori resistance to metronidazole, clarithromycin, amoxycillin, tetracycline and trovafloxacin in The Netherlands
J Antimicrob Chemother
Explanation for variability of omeprazole amoxycillin therapy? Tolerance of H. pylori to amoxycillin
Gastroenterology
Antimicrobial susceptibility of H. pylori in Canada to three key antibiotics: metronidazole, clarithromycin, and amoxicillin
Gastroenterology
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