"Borrelia seems to survive primarily in certain niches within the joints, nervous system, or skin; it is not yet known how it is able to sequester itself in these sites. The spirochete has been recovered from the joint fluid of two patients late in the illness and from lesions of acrodermatitis in one patient as much as ten years after disease onset. These findings and the response of all stages of the illness to antibiotic therapy suggest that the organism may persist, latently or symptomatically in affected tissues for years."
"From months to years after disease onset, sometimes following long periods of latent infection, patients may develop chronic neurologic manifestations of the disorder. The most common form of chronic central nervous system invovement is a subacute encephalotpathy affecting memory, mood or sleep, sometimes with subtle language disturbance.....In addition to encephalopathy, many of these patients also have peripheral sensory symptoms, either distal paresthesias or spinal radicular pain.
Borrelial encephalomyelitis...is a severe disorder characterized by spastic parapareses, ataxia, cognitive impairment, bladder dysfunction, and cranial neuropathy, ...."
The cause of this condition is diffuse and focal involvement of the brain and spinal cord owing to syphilis, usually occurring 5 to 15 years after the primary infection.