[Rapidly progressing dementia as the presenting symptom of Waldenstrom's macroglobulinemia: findings from magnetic resonance imaging of the brain in Bing Neel syndrome].

CASE REPORT: A 68 year old male with no relevant clinical history was admitted to hospital because of symptoms of cognitive impairment (attentional deficit, short term memory disorders and behavioural disorders), accompanied by apraxia of gait and rectal and urinary incontinence. Results of a general clinical exploration were normal. In the MRI study of the brain numerous areas of hypersignal were observed in different arterial territories, which stood out in the T2, FLAIR and, above all, in diffusion weighted sequences. Analytical studies showed hypergammaglobulinemia with monoclonal IgM k and a bone marrow biopsy revealed infiltration by plasmatic cells. Bing Neel syndrome was diagnosed. CONCLUSIONS: We underline this exceptional form of presentation of Waldenstrom's macroglobulinemia and highlight the findings of diffusion weighted MRI, which suggested multiple infarcts for which a neoplastic vascular obstruction mechanism similar to that involved in malignant angioendotheliomatosis is posited.