Susceptibility of the Lyme disease spirochete to seven antimicrobial agents

• Published in: The Yale journal of biology & medicine Vol. 57; no. 4; pp. 549 - 553
• Main Authors: Johnson, S.E, Klein, G.C, Schmid, G.P, Feeley, J.C
• Format: Journal Article
• Language: English
• Published: United States Yale Journal of Biology and Medicine 1984
• Subjects: Anti-Bacterial Agents - therapeutic use; antibiotics; Borrelia; Borrelia burgdorferi; Dose-Response Relationship, Drug; Humans; Ixodidae; Lyme Disease - drug therapy; Microbial Sensitivity Tests; Spirochaetaceae; Spirochaetales - drug effects
• ISSN: 0044-0086; 1551-4056

The antimicrobial susceptibility of five Lyme disease spirochete strains (two human and three tick isolates) was determined. A macrodilution broth technique was used to determine on three separate test occasions the minimal inhibitory concentrations (MICs) of seven antibiotics. The Lyme disease spirochete was most susceptible to erythromycin with a MIC of less than or equal to 0.06 micrograms/ml. The spirochete was also found to be susceptible to minocycline, ampicillin, doxycycline, and tetracycline-HCL with respective mean MICs of less than or equal to 0.13, less than or equal to 0.25, less than or equal to 0.63, and less than or equal to 0.79 micrograms/ml. The spirochete was moderately susceptible to penicillin G with a mean MIC of 0.93 micrograms/ml. All strains were resistant to rifampin at the highest concentration tested (16.0 micrograms/ml).