March 17, 1975

Antimicrobial Resistance of Shigellae Isolated in Michigan

Author Affiliations

From the departments of human development and microbiology and public health, College of Human Medicine, Michigan State University, East Lansing. Dr. Thompson is an Epidemic Intelligence Officer, Center for Disease Control, with the Michigan Department of Public Health.

JAMA. 1975;231(11):1159-1161. doi:10.1001/jama.1975.03240230033016

Patterns of antimicrobial resistance were studied for 213 strains of shigellae isolated in rural and urban areas of Michigan by quantitative techniques: 66% of these organisms were resistant to ampicillin, tetracycline, cephalexin, or chloramphenicol or had multiple resistance to various combinations of these antibiotics. The incidence of resistant organisms was higher in the Detroit-Wayne County area, which is the most urban part of the state. Nalidixic acid and oxolinic acid were noted to be quite effective in vitro against shigellae and perhaps warrant further clinical study as potential agents for therapy of shigellosis, especially in view of the appearance of isolates with multiple resistance. Sulfamethoxazole alone was effective against only 62% of the Shigella isolates tested, but mixture with trimethoprim in a 20:1 ratio yielded a highly active in vitro combination.

(JAMA 231:1159-1161, 1975)