Neurological involvement in brucellosis; clinical classification, treatment and results

The aim of this retrospective study was to describe and to categorize different clinical pictures of patients with neurobrucellosis in our clinic, and present demographical and laboratory data about the patients. Hospital records of 430 patients with brucellosis between 2003 and 2009, were retrospectively reviewed. Out of 430 patients, 19 (4.4%) had neurobrucellosis. These patients were classified into four groups: Meningitis group (n= 14, 13 cases of subacute/chronic meningitis, one case of acute meningitis), encephalomyelitis group (n= 3, one case of meningoencephalomyelitis, one case of cerebellar abscess and one case of transverse myelitis), polyradicular group (n= 1, Miller-Fisher Syndrome), and others (n= 1, one case of intradural abscess). Ten patients (52.6%) were female, and the mean age of the patients was 48.8 years. About 47.4% of the patients had fever, 26% of the patients had neck stiffness and 5% of the patients were in an unconscious state. Out of 19 patients, 18 underwent lumbar puncture and they had positive brucella antibody test in cerebrospinal fluid (CSF) by standard tube agglutination method. Brucella spp. Were grown in four patient's blood culture and one patient's CSF culture. There were cranial nerve involvement in five cases, the most frequent being the sixth cranial nerve. Out of 19 patients, three recovered with sequela (paraparesis, hearing loss, dementia and sphincter disfunction) and 16 patients recovered completely. Although neurobrucellosis is most frequently presented as subacute/chronic meningitis, it may be associated with different clinical pictures. The classical triad of meningitis (fever, neck stiffness, unconsciousness) is rarely seen in brucellosis-related meningitis. Brucellosis should be kept in mind in patients with unexplained neurological findings particularly in areas where brucellosis is endemic. In addition, a current classification of neurobrucellosis, related to involved location of nervous system, clinical picture and pathogenesis, is needed.