Myelitis and Polyradiculoneuropathy With Severe Pain: Unusual Neurological Manifestations as Presenting Symptoms of Brucellosis.

Brucellosis, an endemic zoonosis in Portugal, is a multisystem disease, presenting with neurological manifestations in up to 25% of cases. Neurobrucellosis diagnostic criteria include evidence of central nervous system invasion, either by documenting increased blood-brain barrier permeability that normalizes after treatment or by Brucella isolation. We report 2 patients with systemic brucellosis presenting with neurological symptoms: A 28-year-old female with progressive hemiparesis associated with severe refractory thoracic and lumbar pain, whose spinal magnetic resonance imaging identified longitudinally extensive myelitis. Brucella agglutination test was positive in blood; however, cerebrospinal fluid cytochemical, serological testing, and cultures were negative. A 58-year-old male with intermittent fever in the evening, associated with severe refractory cervical and lumbar spinal and radicular pain. Blood workup identified leukocytosis, elevated inflammatory markers and positive Brucella agglutination test. Cerebrospinal fluid presented mild protein increase and negative serological testing and cultures. Electromyogram revealed demyelinating polyradiculoneuropathy. In both cases, antibiotic therapy induced symptom resolution. Despite the neurological presentation, no evidence of direct nervous system infection was found. An indirect mechanism appears to be involved, such as a parainfectious syndrome or circulating endotoxins release by the bacteria. Brucellosis should be considered in patients presenting with inflammatory neurological symptoms in endemic regions. Prompt diagnosis and treatment are important as chronic infection has significant morbidity.