Analysis of Borrelia burgdorferi sensu lato isolated from cerebrospinal fluid

Involvement of the nervous system in Lyme borreliosis may occur with or wit hout erythema migrans and it may present with a variety of neurological sym ptoms. In this study we analysed phenotypic and genotypic characteristics o f 40 Borrelia strains isolated from cerebrospinal fluid (CSF) of 38 Sloveni an patients with different clinical manifestations of Lyme borreliosis. In seven of the patients, Borreliae were also isolated from skin lesions. Spec ies identification and plasmid profiles were determined by pulsed-field gel electrophoresis and protein profiles by SDS-PAGE. MIO digestion profiles o f Borrelia burgdorferi sensu lato DNA showed that 25 (62.5%) isolates were B. garinii, 14 (35%) B. afzelii, and one (2.5%) B. burgdorferi sensu strict o. All strains, except one, possessed a large plasmid and a varying number of smaller plasmids, Three (7.5%) isolates exhibited an unusual plasmid pro file, with a large plasmid dimer or three copies of the large plasmid. In p rotein analyses, all strains expressed OspA protein. OspB was present signi ficantly more often in B. afzelli than B. garinii strains (p=0.0000), while OspC was more often present in B. garinii than B. afzelii strains (p=0.005 2). In the seven patients with Borreliae isolated also from the skin, the C SF and skin isolates were identical, either B. garinii (six patients) or B. afzelii (one patient). Species and plasmid heterogeneity as well as antige n diversity could play a role in the pathogenesis of the infection. When co mbined with our own earlier data, the results suggest species-related organ otropism.