A Case of Idiopathic Basal Ganglia Calcification Associated with Membranoproliferative Glomerulonephritis

Idiopathic basal ganglia calcification (IBGC) is a syndrome in which bilateral cerebral calcification occurs despite the absence of abnormal calcium metabolism. A 17-year-old Japanese female was admitted for investigation of intermittent proteinuria from the age of 12 years. On admission, her blood pressure was 126/60 mmHg and her serum creatinine was 0.8 mg/dL. Although computed tomography revealed bilateral striopallidodentate calcinosis, her level of intelligence and neurological findings were normal, as were the results of endocrine tests including parathyroid hormone. Asymptomatic IBGC was diagnosed. Renal biopsy showed membranoproliferative glomerulonephritis. Peritoneal dialysis was started for end-stage renal failure when she was 24 years old. Pyramidal and extrapyramidal signs started to develop at the age of 27 years and progressed, resulting in death from aspiration pneumonia at the age of 32 years. Post-mortem revealed bilateral calcification of the basal ganglia, dentate nucleus, thalamus, and centrum semiovale. On light microscopy, there was circumferential calcification of the media and intima of affected vessels in the brain, including small arteries, small veins, and capillaries, and luminal narrowing was seen. On electron microscopy, layers of differing electron density were arranged in concentric laminae. This is the first report of IBGC with bilateral and symmetrical cerebral calcification accompanied by membranoproliferative glomerulonephritis resulting in end-stage renal failure.