CHATSUWAN T, PATON F, HEADING RC, AMYES SG; Interscience Conference on Antimicrobial Agents and Chemotherapy (41st : 2001 : Chicago, Ill.).
Abstr Intersci Conf Antimicrob Agents Chemother Intersci Conf Antimicrob Agents Chemother. 2001 Dec 16-19; 41: abstract no. C2-61.
University Of Edinburgh, Edinburgh, United Kingdom
Antimicrobial resistance in Helicobacter pylori has been associated with treatment failure. Between December 1999 and February 2001, a total of 100 H. pylori strains (24%) were isolated from 418 antral biopsies of patients undergoing endoscopy in Edinburgh. Antimicrobial susceptibility patterns were determined by E test. Mutations in the 23S rRNA and the Quinolone Resistant-Determining Region (QRDR) of gyrA gene were investigated for the mechanisms of macrolide and fluoroquinolone resistances, respectively. MIC[50] and MIC[90] values are shown below. Resistance to clarithromycin and erythromycin was found in 9% and 10% of the H. pylori strains, respectively. All clarithromycin-resistant strains had erythromycin MIC of >256 mg/L. Metronidazole resistance was found in 8%. Ciprofloxacin resistance was demonstrated in 2%. Resistance to amoxycillin was not detected. [table: see text] Fluoroquinolone resistance was associated with alterations in the QRDR of gyrA gene. Mutation at position 91 (Asp to Asn) was found in both ciprofloxacin-resistant strains. Seven of the ten macrolide-resistant isolates had mutations in the 23S rRNA at position 2143 (A to G). Two also had an additional T to C mutation at either position 2182 or 1934. Of the ten isolates, two carried a single mutation at either position 2182 (T to C) or 2195 (C to T). Mutation at position 2182 has previously been found not to be associated with macrolide resistance. However, the mutations at position at 1934 and position 2195 have not previously been identified. No mutation was detected in one isolate. The results imply that different mechanisms are responsible for macrolide resistance in our H. pylori strains.
Publication Types:
Keywords:
- Amoxicillin
- Anti-Bacterial Agents
- Clarithromycin
- Erythromycin
- Fluoroquinolones
- Helicobacter pylori
- Humans
- Metronidazole
- Microbial Sensitivity Tests
- Mutation
- Scotland
- genetics
Other ID:
UI: 102270382
From Meeting Abstracts