IMG-17. Expanding the radiological spectrum of Bing-Neel syndrome: a case report

Bing-Neel Syndrome (BNS) is a rare neurological complication of lymphoplasmacytic lymphoma (LPL), also known as Waldenström macroglobulinemia (WM). It has been reported in approximately 0.8% of patients with LPL1. It is more common in older men. Clinical presentations are heterogeneous, and MRI findings are variable, with the most common being leptomeningeal enhancement2. Here, we present a case of a woman with atypical MRI findings. A 59-year-old woman presented to the neurology clinic for evaluation of transient neurological deficits, including loss of consciousness and nonsensical speech. Her medical history was significant for monoclonal gammopathy of undetermined significance (MGUS), which later progressed to IgG-predominant LPL, MYD88 p.L273P positive, diagnosed approximately 10 years earlier. At evaluation, she reported fatigue, weight loss, and cognitive slowing, though her neurological examination was unremarkable. Brain MRI showed confluent T2 FLAIR hyperintensities in the bilateral white matter without enhancement. Spinal MRI revealed diffuse T2 hyperintensity extending to the conus, also non-enhancing. Cerebrospinal fluid analysis demonstrated lymphocytic pleocytosis and markedly elevated protein (316 mg/dL). Given concern for BNS, she was referred to neuro-oncology. Due to the atypical imaging findings, she underwent an extensive workup that excluded infectious, autoimmune, and paraneoplastic etiologies. She was ultimately diagnosed with BNS and started on a Bruton’s tyrosine kinase (BTK) inhibitor. BNS remains a diagnostic challenge due to its rarity, heterogeneous clinical presentation, and variable MRI findings. Diagnostic delays often result in delayed treatment. This case adds to the literature by illustrating a patient who presented with atypical MRI findings, which contributed to a delayed diagnosis. A high index of suspicion is warranted in patients with a history of LPL who present with neurological symptoms and abnormal imaging, even in the absence of typical leptomeningeal enhancement. Although the prognosis for BNS remains poor, recent advances in treatment, when implemented early, may prolong survival2.