Incidence of Neurobrucellosis from Central India: A Hospital Based Study

Introduction: Despite being a rare complication, neurobrucellosis can be a major cause of neurological morbidity and mortality if not adequately diagnosed and treated. Aim: In the present study, we report utility of antibody based immunoassay protocol for diagnosis and incidence of neurobrucellosis in suspected cases with neurological complications in our hospital. Materials and Methods: This was a prospective cohort study conducted in Central India Institute of Medical Sciences, Nagpur, Maharashtra, India (April 2015 to March 2016). A total of 60 suspected participants with neurological abnormality were prospectively recruited and screened for the disease using commercially available IgG and IgM antibody detection kits. Conventional tests like Standard Tube Agglutination Test (STAT) and Rose Bengal Test (RBT), Brucella culture were also performed to compare positivity rates of evaluated tests in Cerebrospinal Fluid (CSF). Clinical characteristics were summarised in terms of percentages for categorical variables, i.e., age groups, gender, signs and symptoms. All statistical analysis was carried out using MedCalc software version 10.1.2.0. Results: A total of 13 patients showed IgG positivity against Brucella while 7 cases were positive for IgM antibody out of 60 screened cases. The sensitivity and specificity of both IgG and IgM assay was aroud 100%, 82% and 100%, 83% respectively. About 6 (10%) cases showed positivity for both IgG and IgM antibodies. About 9 (64%) out of 14 IgG/IgM positive cases showed positivity in STAT, while 8 (57%) cases showed agglutination in RBT. Only 1 (1.3%) patient showed culture positivity and was positive for IgM, STAT and RBT. Among neurological complications, meningitis was a major complication observed in 7 (50%) of IgG/IgM positive cases whereas hydrocephalus was found in 6 (43%) instances. Conclusion: Doctors should take the likelihood of neurobrucellosis in the patients exhibiting high risk for brucellosis with unexplained neurological behaviour. Diagnosis of neurobrucellosis using an Enzyme-linked Immunosorbent Assay (ELISA) based detection assay showed good sensitivity and specificity and therefore should be used as adjunct tests with other convential assays for rapid screening and treatment initiation in neurobrucellosis cases.