Abstract
A 76-year-old male Caucasian patient was treated in our hospital for acutely decompensated heart failure due to restrictive cardiomyopathy. Acute-on-chronic kidney failure developed with serum creatinine rising from 160 to 345 μmol/L (1.8-3.9 mg/dL); therefore, a kidney biopsy was performed. Besides secondary focal-segmental glomerulosclerosis and minimal amyloidosis, histological analysis showed zebra bodies in the cytoplasm of some podocytes, suggesting renal phospholipidosis (PL). Possible causes for this storage disorder encompass Fabry's disease, in rare cases silicosis, and an iatrogenic drug-induced aetiology. The main suspects are cationic amphiphilic drugs, such as amiodarone and chloroquine. The only cationic amphiphilic drug our patient had taken was the anti-anginal ranolazine, a compound not yet associated with PL. The patient had taken ranolazine for diastolic dysfunction over a period of 9 months until 6 weeks before renal biopsy. In the absence of a hereditary disorder, silicosis and well-known pharmaceutical triggers, a causative role of ranolazine seems likely, and this drug should be considered in the differential diagnosis of drug-induced PL.