Evaluation of in-vitro antibiotic susceptibility of different morphological forms of Borrelia burgdorferi Original Research(298) Article views click here
Authors: Sapi E, Kaur N, Anyanwu S, Luecke DF, Datar A, Patel S, Rossi M, Stricker RB Published Date May 2011 , Volume 2011:4 Pages 97 - 113 DOI 10.2147/IDR.S19201 Eva Sapi1, Navroop Kaur1, Samuel Anyanwu1, David F Luecke1, Akshita Datar1, Seema Patel1, Michael Rossi1, Raphael B Stricker2 1Lyme Disease Research Group, Department of Biology and Environmental Sciences, University of New Haven, New Haven, CT, USA; 2International Lyme and Associated Diseases Society, Bethesda, MD, USA
BackgroundLyme disease is a tick-borne illness caused by the spirochete Borrelia burgdorferi. Although antibiotic therapy is usually effective early in the disease, relapse may occur when administration of antibiotics is discontinued. Studies have suggested that resistance and recurrence of Lyme disease might be due to formation of different morphological forms of B. burgdorferi, namely round bodies (cysts) and biofilm-like colonies. Better understanding of the effect of antibiotics on all morphological forms of B. burgdorferi is therefore crucial to provide effective therapy for Lyme disease.
MethodsThree morphological forms of B. burgdorferi (spirochetes, round bodies, and biofilm-like colonies) were generated using novel culture methods. Minimum inhibitory concentration and minimum bactericidal concentration of five antimicrobial agents (doxycycline, amoxicillin, tigecycline, metronidazole, and tinidazole) against spirochetal forms of B. burgdorferi were evaluated using the standard published microdilution technique. The susceptibility of spirochetal and round body forms to the antibiotics was then tested using fluorescent microscopy (BacLight™ viability staining) and dark field microscopy (direct cell counting), and these results were compared with the microdilution technique. Qualitative and quantitative effects of the antibiotics against biofilm-like colonies were assessed using fluorescent microscopy and dark field microscopy, respectively.
ResultsDoxycycline reduced spirochetal structures ~90% but increased the number of round body forms about twofold. Amoxicillin reduced spirochetal forms by ~85%–90% and round body forms by ~68%, while treatment with metronidazole led to reduction of spirochetal structures by ~90% and round body forms by ~80%. Tigecycline and tinidazole treatment reduced both spirochetal and round body forms by ~80%–90%. When quantitative effects on biofilm-like colonies were evaluated, the five antibiotics reduced formation of these colonies by only 30%–55%. In terms of qualitative effects, only tinidazole reduced viable organisms by ~90%. Following treatment with the other antibiotics, viable organisms were detected in 70%–85% of the biofilm-like colonies.
Conclusion Antibiotics have varying effects on the different morphological forms of B. burgdorferi. Persistence of viable organisms in round body forms and biofilm-like colonies may explain treatment failure and persistent symptoms following antibiotic therapy of Lyme disease.
This is a welcome study, my own experience was that different antibiotics improved some symptoms more than others but then other antibiotics improved different symptoms and the best improvements were on bi therapy.
The lack of access to knowledgeable and experienced doctors in this field unless we have a bottomless purse makes finding the best treatment options for each of us very problematic.
'Newer approaches to the treatment of Lyme disease should take into account the frequent co-infection with other pathogens and the need of a more prolonged combination therapy, as it is the case in the treatment of tuberculosis. Even in the doubt of tuberculosis the treatment of the patients with "tritherapy" is necessary for 6 months. It should be an example for the future treatment of Lyme disease. Such treatment, in analogy to tuberculosis and syphilis will substantially prevent extensive healthcare costs in the future.'