Antimicrobial susceptibility of Helicobacter pylori strains isolated from patients in Shiraz, Southern Iran.
OBJECTIVE
To improve our understanding of Iranian regional variation in Helicobacter pylori (H. pylori) antibiotic resistance rates to find the best antibiotic therapy for eradication of H. pylori infections.


METHODS
A total of 266 patients undergoing endoscopy in Shiraz, Southern Iran, were included in this study. H. pylori strains were isolated from antral biopsies by culture and confirmed by the rapid urease-test and gram staining. Antibiotic susceptibility of H. pylori isolates was determined by E-test.


RESULTS
A total of 121 H. pylori strains were isolated, 50 from male and 71 from female patients. Data showed that 44% (n = 53), 20% (n = 24), 5% (n = 6), and 3% (n = 4) of all strains were resistant to the antibiotics metronidazole, amoxicillin, clarithromycin, and tetracycline, respectively. When the antibiotics were considered together we found 11 sensitivity patterns for the strains. Resistance to metronidazole was significantly higher in female than in male patients (P < 0.05). In about 71% of the metronidazole-resistant isolates, the minimum inhibitory concentrations (MICs) exceeded 256 μg/mL.


CONCLUSIONS
We found a moderate rate of primary resistance to metronidazole. However, a high MIC (> 256 mg/L) which was found in 71% of the isolates is considerable. In the case of amoxicillin, an increased resistance rate of 20% is worrying. Resistance to clarithromycin and tetracycline is also emerging among the H. pylori strains in our region.
Professor Alborzi Clinical Microbiology Research Center, Shiraz University of Medical Sciences, Nemazee Hospital, Shiraz 71937-11351, Iran. farshads@sums.ac.ir
Shohreh
S
Farshad
Abdolvahab
A
Alborzi
Aziz
A
Japoni
Reza
R
Ranjbar
Kazem
K
Hosseini Asl
Parisa
P
Badiee
Maneli
M
Amin Shahidi
Marziyeh
M
Hosseini
D000890:Anti-Infective Agents / Q000627:therapeutic use*; D001706:Biopsy; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D005773:Gastroscopy; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D016480:Helicobacter pylori / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008826:Microbial Sensitivity Tests; D014510:Urease / Q000032:analysis
D000890:Anti-Infective Agents; D014510:Urease