Posterior leukoencephalopathy syndrome (PLES) is an edematous brain lesion which predominantly affects the cerebral white matter. It can be drug induced and has been described as calcineurine inhibitors (CI) related neurotoxicity. Although the mechanism still unclear, but disruption of blood brain barrier and effect on vascular endothelium with release of potent vasoconstrictors may be a possible pathogenesis.
We retrospectively report four post kidney transplant patients treated with calcineurine inhibitors who developed PLES. Three of these patients were on tacrolimus and one was on cyclosporine A. Mean age was 28 years (range 16-36), 3 females and one male. Mean interval from transplantation to onset of the syndrome was 18 months (range 4-72 months). Apart from hypertension, no risk factors could be identified. Three patients had mild to moderate hypertension and only one was severely hypertensive. The presenting neurological features were recurrent generalized tonic clonic seizures, altered mental status and visual disturbances. MRI changes were confined to white matter with subcortical edema mainly including parieto-occipital lobes. Clinical and investigational work up was done for exclusion of CNS infections, hypertensive encephalopathy, ischemic infarcts and progressive multifocal leukoencephalopathy. No significant correlation was detected with any of serum level neither of creatinine, sodium, calcium, cholesterol, nor with platelet counts, CI drug level or blood pressure at presentation. Complete clinical and neuroimaging recovery occurred with proper control of hypertension and either reduction of dose of CI (three patients) or discontinuation (one patient). Follow up of patients for 18 months showed neither recurrence nor other complications. PLES may develop in post kidney transplant patient treated with CI. Complete neurological recovery is the outcome with early recognition and management by proper control of hypertension and discontinuation or reduction of dose of CI.