Vascular occlusion: Atypical presentation of neurobrucellosis as a sequelae to Brucella abortus infection

Neurobrucellosis is a serious complication of brucellosis, a zoonotic infection caused primarily by Brucella melitensis.¹ It accounts for 5%–7% of brucellosis cases, has varied clinical features and may manifest as part of systemic brucellosis or as isolated disease.^2,3

A 23-year-old male presented with a history of fever for 7 days and decreased communication, along with abnormal behaviour for 1 day. He lived in a rural area and reared livestock, but did not consume raw milk. On examination, the patient was agitated and disoriented. His lower limbs had increased tone, neck rigidity was present, and the Babinski was bilateral extensor. All other systems were within normal limits. His haemoglobin was 13.7 g/dl, and leucocyte count was 5610/cmm. Liver function, renal function, urine analysis, and serum electrolytes were normal. Cerebrospinal fluid (CSF) analysis showed proteins: 198 mg/dl; glucose: 18 mg/dl (concomitant blood glucose 117 mg/dl), adenosine deaminase: 3.2 U/L, and microscopy: total leucocyte count of 260 cells/cmm with lymphocytic pleocytosis. Initial CSF culture was sterile and negative for herpes simplex virus 1 and 2, and cryptococcus. A cartridge-based nucleic acid amplification test on CSF was negative. The chest X-ray was normal. Tuberculin sensitivity and IFNg release assay were also negative. Vasculitis work-up (antinuclear antibody, perinuclear anti-neutrophil cytoplasmic antibody, cytoplasmic antineutrophil cytoplasmic antibody) was negative. The neuroimaging findings are shown in Figs. 1–3. Serology was positive for Brucella via Rose Bengal Test (RBT) (Fig. 4), with borderline IgM and positive IgG antibodies. CSF polymerase chain reaction (PCR) confirmed Brucella, with serum agglutination test titre of 1:80. Cultures yielded Brucella abortus (Fig. 5), with speciation confirmed through PCR (Figs. 6,7). The patient was started on ceftriaxone, doxycycline, and rifampicin. At discharge, the patient was afebrile but had cerebellar ataxia and neck titubation. All drugs were continued for 3 months. After 3 months, the patient was afebrile, had a normal appetite, but still had ataxia, incoordination, and neck titubation. Patient declined a repeat spinal tap.

Close

FIG 1.

Axial fluid-attenuated inversion recovery image showing multiple hyperintensities in the cerebellum on both sides

Export to PPT

Close

FIG 2.

Computed tomograph angiography showing non opacified right posterior cerebral artery

Export to PPT

Close

FIG 3.

Computed tomography angiography showing non-opacified V4 segment of the left vertebral artery

Export to PPT

Close

FIG 4.

Rose Bengal plate test–serum agglutination (left), negative control (right)

Export to PPT

Close

FIG 5.

Growth of smooth colonies on Brucella selective medium

Export to PPT

Close

FIG 6.

Brucella sp., identification using JPF/JPR primers: Lanes 1 ladder 100 bp; 2 test sample, 3 reference sample, 4 empty lane, 5 positive control, 6 empty lane forward primer (JPF) reverse primer (JPR)

Export to PPT

Close

FIG 7.

Brucella abortus identification using IS711/Brucella abortus/Brucella melitensis primers: Lanes 1 1 kb ladder; 2 to 4 random Brucella suspected samples, 5 to 8 Rose Bengal plate test positive samples, 9 test sample, 10 to 12 animal outbreak samples

Export to PPT

In India, the incidence of human brucellosis varies regionally, ranging from 0.8% in Kashmir to 19.83% in Maharashtra.⁴ Patients typically present with fever, headache, hearing loss, seizures, and altered sensorium. Patra et al. (221 cases), showed that meningitis was the most common manifestation (32.6%). Others reported VIII nerve involvement, encephalitis, cerebellar involvement, polyradiculopathy, and myelitis.⁵ Vascular complications are rare, presenting as stroke or venous thrombosis, likely due to Brucella-induced vasculitis, endothelial injury, and prothrombotic state.^6,7 The imaging findings can be divided into normal, inflammation, white matter changes, and vascular changes.⁸ The Istanbul-3 study found the most common magnetic resonance imaging pattern to be inflammatory, including meningeal enhancement, abscesses, granulomas, nerve root enhancement, and arachnoiditis. White matter changes manifest as hyperintense lesions on T2-weighted images.⁹ CSF findings include lymphocytic pleocytosis, raised protein, and hypoglycorrhachia.⁵ Confirmation is by positive blood or CSF culture or detection of Brucella antibodies in serum or CSF using standard agglutination tests or enzyme-linked immunosorbent assay. Management includes dual- or triple-combination therapy with doxycycline, rifampicin, trimethoprim-sulphamethoxazole, streptomycin, or ceftriaxone for 3–6 months.¹⁰