Wien Klin Wochenschr. 2002 Jul 31;114,13-14:574-9. Cystic forms of Borrelia burgdorferi sensu lato: induction, development, and the role of RpoS. Murgia R, Piazzetta C, Cinco M. Dipartimento di Scienze Biomediche, sez. Microbiologia, Università degli Studi di Trieste, Trieste, Italy. rmurgia@dsbmail.units.it 60It has been demonstrated recently that cells of Borrelia burgdorferi sensu lato, the etiological agent of Lyme disease, transform from mobile spirochetes into nonmotile cystic forms in the presence of certain unfavourable conditions, and that cystic forms are able to reconvert to vegetative spirochetes in vitro and in vivo. T he purpose of this study was to investigate the kinetics of conversion of borreliae to cysts in different stress conditions such as starvation media or the presence of different antibiotics. Using the same experimental conditions we also investigated the possible role in cyst formation of RpoS, an alternative sigma factor that controls a regulon in response to starvation and transition to stationary phase. We observed that beta-lactams penicillin G and ceftriaxone, the antibiotics of choice in Lyme borreliosis treatment, favoured the production of cysts when used with serum-depleted BSK medium. In contrast, we observed a low level of cyst formation in the presence of macrolides and tetracyclines. In order to elucidate the role of the rpoS gene in cyst formation we analyzed the reaction of the rpoS mutant strain in comparison with its wild-type in different conditions. Under the same stimuli, both the wild-type borrelia and the rpoS knock-out isogenic strain produced cystic forms with similar kinetics, thus excluding the participation of the gene in this phenomenon. Our findings suggest that cyst formation is mainly due to a physical-chemical rearrangement of the outer membrane of Borrelia burgdorferi sensu lato leading to membrane fusion and controlled by different regulation mechanisms. 87.5: Acta Neurol Scand. 2002 Oct;106(4):205-8. Chronic symptoms are common in patients with neuroborreliosis -- a questionnaire follow-up study. Vrethem M, Hellblom L, Widlund M, Ahl M, Danielsson O, Ernerudh J, Forsberg P. Division of Neurology, University Hospital, Linköping, Sweden, Division of Neurophysiology, University Hospital, Linköping, Sweden. magnus.vrethem@lio.se OBJECTIVES: The existence of chronic neuroborreliosis is controversial. The aim of our study was to investigate the existence and kind of persistent symptoms in patients previously treated because of neurological symptoms as a result of neuroborreliosis. MATERIALS AND METHODS: A total of 106 patients with neuroborreliosis, according to established criteria, and a control group of 123 patients with Borrelia induced erythema migrans diagnosed in a general practitioner office were studied. A questionnaire was sent to patients and controls concerning their health situation. Time from onset of neurological symptoms to the questionnaire send out was 32 months, mean, for the patients with neuroborreliosis and 33 months , mean, for the controls. RESULTS: Fifty per cent of the individuals in the patient group compared with 16% of the individuals in the control group showed persistent complaints after their Borrelia infection, P < 0.0001. The most significant differences between the groups were the presence of neuropsychiatric symptoms such as headache, attention problems, memory difficulties and 61depression. Paresthesia, pain and persistent facial palsy was also significantly more common in patients treated because of neuroborreliosis. CONCLUSION: Our study shows that persisting neurological symptoms are common after a neuroborreliosis infection. The pathological mechanisms that lay behind the development of chronic symptoms, however, are still uncertain
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