ABSTRACT
BACKGROUND: Infectious agents have been suspected as a triggering factor for development of autoimmune thyroid disease (ATD). Some reports from Western countries have suggested association between Helicobacter pylori (HP) infection and ATD. OBJECTIVE: To investigate the association of ATD with Cag A seropositivity in a population with high rate and early age of onset of HP infection. METHODS: IgG anti HP and anti Cag A antibodies were measured in 88 patients with ATD and compared with results of 112 healthy individuals. RESULTS: The rate of infection with HP was not significantly different in patient and control groups, but there was significant association between ATD and infection with Cag A strains (p<0.005). This association was significant for both hypothyroidism (p<0.005) and Graves' disease (p<0.02). Cag A antibody level correlated with titers of thyroid auto antibodies (p<0.001). CONCLUSION: In a population with high rate and early age of onset of HP infection, only infection with Cag A positive strains is associated with ATD, and this may be due to immune cross-reactivity.
Subject(s)
Antigens, Bacterial/immunology , Autoimmune Diseases/immunology , Bacterial Proteins/immunology , Helicobacter Infections/immunology , Helicobacter pylori/immunology , Thyroid Diseases/immunology , Adolescent , Adult , Antibodies, Bacterial/immunology , Autoimmune Diseases/microbiology , Female , Graves Disease/immunology , Graves Disease/microbiology , Helicobacter Infections/microbiology , Helicobacter pylori/physiology , Host-Pathogen Interactions/immunology , Humans , Hypothyroidism/immunology , Hypothyroidism/microbiology , Immunoglobulin G/immunology , Iran , Male , Middle Aged , Thyroid Diseases/microbiology , Young AdultABSTRACT
AIM: 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. CONCLUSION: 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.
