[A case of Staphylococcus aureus meningitis associated with cryoglobulin-related renal failure and clinically mild encephalitis/encephalopathy with a reversible splenial lesion].

A 59-years old man, having untreated hypertension and diabetes, was admitted to our hospital because of lumbago and fever. A T2-weighted image of spine showed increased signal intensity of vertebra at L3 and L4. Methicillin-susceptible staphylococcus aureus (MSSA) infection was confirmed by blood culturing. Cerebrospinal fluid (CSF) analysis showed pleocytosis. Diagsosis of pyogenic spondylitis with bacterial meningitis was made. Diffusion-weighted magnetic imaging of the brain disclosed a focal hyperintense lesion in the corpus callosum which showed a low coefficient in the apparent diffusion coefficient mapping. This finding suggests a clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS). His symptoms temporarily ameliorated by antibiotic therapy. Two weeks later, however, his conscious level rapidly worsened to comatose state. Concomitantly he developed acute renal failure with severe proteinuria. Serum serology showed a positive cryoglobulin test. Mechanical ventilation, hemodialysis and steroid pulse therapy improved his consciousness with a resultant complete recovery of all symptoms. We emphasize the possible complications in some cases of MERS.