BORRELIA-BURGDORFERI SENSU-LATO STRAINS ISOLATED FROM CUTANEOUS LYME BORRELIOSIS BIOPSIES DIFFERENTIATED BY PULSED-FIELD GEL-ELECTROPHORESIS

25 skin biopsy isolates of Borrelia burgdorferi sensu lato, mainly fro m German patients with erythema migrans [EM], borrelial lymphocytoma [ BL] and acrodermatitis chronica atrophicans [ACA], were species-differ entiated using pulsed-field gel electrophoresis (PFGE). The isolates r evealed 15 B. afzelii, 8 B. garinii and 2 B. burgdorferi sensu stricto species according to MluI digestion. All 6 ACA isolates were identifi ed as B. afzelii species, whereas the 2 borrelial lymphocytoma isolate s were grouped into B. garinii species. 12 B. afzelii strains, includi ng 4 ACA isolates, were further investigated by digestion with 5 restr iction enzymes, Most of the strains revealed an individual pattern. No specific characteristically large restriction fragment pattern (LRFP) could be detected within the ACA and/or EM group. The ACA isolates co uld not be clearly differentiated from the EM isolates according to th e LRFP patterns. PFGE is thus a highly effective method for detecting differences among B. afzelii isolates.