[Reversible posterior leukoencephalopathy in a patient receiving cyclosporin therapy]

We reported a case of reversible posterior leukoencephalopathy syndrome (RPLS) that occurred during cyclosporin A (CyA) therapy for fulminant hepatitis. A 22-year-old man was given an intravenous drip of interferon-beta, metylprednisolone sodium succinate and CyA, and also received plasma exchange and hemodiafiltration. On the 7th day of the intravenous CyA therapy, in which its dose had been increased from 60 mg/day to 84 mg/day, he became somnolent and had headache, double vision, hallucination and then a generalized tonic-clonic seizure. The blood CyA concentration increased to a level as high as 455 ng/ml. Brain computed tomography (CT) scan without contrast medium revealed symmetric low-density areas in the bilateral occipital white matter and partly in the cortex. T2-weighted magnetic resonance imaging (MRI) showed an increased signal intensity, and single-photon emission CT using 99 mTc showed a hypoperfusion of cerebral blood flow in those areas. After CyA administration was changed to 100 mg/day orally to decrease its uptake in the blood, his consciousness and vision recovered within 4 weeks. Then abnormalities in MRI findings completely disappeared. On the basis of the clinical course and time-sequential change of serum CyA level in this patient, he was diagnosed as having RPLS caused by CyA therapy. Recently, the number of cases of RPLS has increased in the Western countries. However, there are few reports of RPLS after CyA therapy in Japan. From this case, we emphasize that careful following up the patient's neurological findings during CyA therapy is very important and that a cranial MRI is an essential tool for the diagnosis of RPLS.