Vol.53 No.4 April 2005

Annual survey of Helicobacter pylori susceptibility to clarithromycin and amoxicillin after approval of antibiotic eradication H. pylori

Intetsu Kobayashi, Takeshi Saika, Akiko Kanayama, Kaoru Matsuzaki, Miyuki Hasegawa and Yumie Sato

Chemotherapy Division, Mitsubishi Kagaku Bio-Clinical Laboratories, Inc.,
3-30-1 Shimura, Itabashi-ku, Tokyo, Japan

Abstract

We studied annual changes in the susceptibility of 300 strains of Helicobacter pylori (H. pylori, 100 strains/year) isolated from clinical specimens of untreated pacients for 3 years from the year after the application of the reimbursement of medical fee to antibiotic eradication of H. pylori.
We found little difference among MIC ranges of clarithromycin (CAM) in 3 years and MIC₉₀ for strains isolated yearly was 16 μg/mL, unchanged in these 3 years. Similar trends were seen in MIC₅₀ and MIC₈₀, which also showed little change. The minimum amoxicillin (AMPC) MIC range was ≤ 0.015 μg/mL annually for 3 years and the maximum MIC was 0.5 μg/mL in 2003. Little change in MIC₅₀, MIC₈₀ and MIC₉₀ was seen in these 3 years. H. pylori strain resistance to CAM in 2002 was slightly higher at 19% over the 14-15% seen in the other 2 years.
We concluded that H. pylori susceptibility to CAM and AMPC change little in the 3 years from the year the application of medical fee reimbursement was approved for H. pylori eradication.

Key word

Helicobacter pylori, Drug susceptibility, clarithromycin, amoxicillin

Received

November 29, 2004

Accepted

February 7, 2005

Jpn. J. Chemother. 53 (4): 277-279, 2005