Pediatric neurobrucellosis and atypical Guillain-Barré syndrome: an intriguing case unveiled.

Brucellosis, a chronic zoonotic disease with a significant global burden, particularly in endemic areas, can also present as neurobrucellosis, a rare complication. We report a case of polyradiculoneuropathy in a pediatric patient resulting from this uncommon presentation. A 5-year-old girl presented with progressive asymmetric lower limb weakness for two weeks that progressed to a loss of ambulation in four weeks. She also had flu-like symptoms and persistent high-grade fever. Her history was notable for ingesting raw milk before the onset of fever. Initial examination revealed meningismus signs and fever. She had bilateral weak hip flexion graded 4/5 on the Medical Research Council (MRC) scale, weak right and left knee flexion (3/5 and 4/5, respectively), and weak right ankle dorsiflexion (4/5). She also had diminished reflexes throughout. The patient exhibited a clinical picture resembling Guillain-Barré Syndrome (GBS) after admission as her weakness progressed. Cerebrospinal fluid (CSF) analysis revealed no cell counts, elevated protein levels (1545 mg/dL), and normal glucose levels (3.34 mmol/L). Blood and CSF cultures were negative, but the serum antibody titer was elevated at 1:1280 against Brucella melitensis and Brucella abortus species. Lumbosacral MRI showed diffuse enhancement of the lower nerve roots. A nerve conduction study (NCS) demonstrated axonal and demyelinating polyradiculoneuropathy. The patient regained her strength three months after presentation, following a course of antibiotics. When evaluating patients with atypical manifestations resembling GBS, brucellosis should be considered an important differential diagnosis in endemic areas.