The use of cyclosporine in a boy with a prior episode of posterior encephalopathy.

We report the case of a 12- year-old Japanese boy who was receiving cyclosporine (Cs A) for steroid-dependent nephrotic syndrome despite a prior episode of Cs A-associated posterior encephalopathy. At the third relapsing of nephrotic syndrome, Cs A was initiated. Eight days after the Cs A therapy, the boy was admitted to the University Hospital of Tsukuba because of generalized convulsion. Magnetic resonance imaging (MRI) showed hyperintense lesions involving the bilateral parieto-occipital region. Cs A was discontinued, and cyclophosphamide was started. The boy had a 6-month drug-free period after the cyclophosphamide treatment and then relapsed three more times in the following 5 months. As the prednisolone dosage could not be decreased to less than 2 mg/kg/48 h, the patient was re-challenged with Cs A 1 1/2 years later. Blood pressure and serum Cs A levels were measured frequently, an anti-hypertensive drug was given, and MRI was done four times to detect hyperintense lesions. He has been receiving Cs A for 9 months, and MRI has revealed no abnormalities. At the latest follow-up, dated 12 April 2004, he was in a remissive state of nephrotic syndrome. This is the first report of giving Cs A to a nephrotic child who had a previous history of Cs A-associated posterior encephalopathy.