Clinical characteristics of neurological involvement in post-treatment Lyme disease syndrome: part 1

Background: Lyme borreliosis (LB) is a prevalent vector-borne infectious disease both in our country and abroad. The term "post-treatment lyme disease syndrome" (PTLDS) is utilized to describe symptoms that emerge within six months of a laboratory-confirmed Borrelia burgdorferi infection and persist for at least six months following the completion of an appropriate course of antibiotic therapy. Aim: to investigate the specific features of neurological involvement as a manifestation of PTLDS and to identify the risk factors associated with its development. Materials and Methods: the study enrolled 91 patients with a definitive diagnosis of LB who presented with neurological symptoms that developed within six months after undergoing the recommended course of antibacterial therapy. Comprehensive clinical, therapeutic, and neurological assessments were performed, incorporating epidemiological data and medical histories regarding typical LB manifestations. Results: the clinical spectrum of neurological involvement was significantly dominated by symptoms of encephalopathy and radiculopathy, with polyneuropathy observed less common; isolated cases of encephalomyelitis and facial nerve palsy were also recorded. Concurrent involvement of both the central and peripheral nervous systems was identified in 41.8% of cases. PTLDS was characterized by a general infectious syndrome (11.0% of subjects) and a combination of neurological and musculoskeletal syndromes (38.5% of patients), with arthralgia occurring significantly more common than myalgia or arthritis. Conclusion: neurological pathology in PTLDS manifests as diverse syndromes involving the central and peripheral nervous systems. Key factors predisposing patients to the development of PTLDS include late diagnosis, and consequently, delayed antibiotic initiation, early infectious dissemination, multiple or repeated tick bites, and the development of neuropsychological disturbances or chronic pain. Keywords: Lyme borreliosis, post-Lyme syndrome, post-treatment Lyme disease syndrome, PTLDS, neurological involvement. For citation: Baranova N.S., Ostapenko Ya.S., Ovsyannikova L.A., Spirin N.N., Baranov A.A., Bykanova M.A. Clinical characteristics of neurological involvement in post-treatment Lyme disease syndrome: part 1. RMJ. 2026;4:7–12. DOI: 10.32364/2225-2282-2026-4-2