Transient D-Penicillamine-Induced Nephrogenic Diabetes Insipidus during Treatment of a Patient with Cystinuria <br/>—D-Penicillamine-Induced Nephrogenic Diabetes Insipidus

Abstract

Background: Diabetes insipidus (DI) is a rare disorder characterized by inappropriate polyuria and hypo-osmolar urine. It is caused by inadequate production of antidiuretic hormone, in response to hypothalamic osmoreceptor-stimulation, from the pituitary gland (central DI) or resistance to its action at terminal distal convoluted tubules and collecting ducts (nephrogenic DI). Most cases of nephrogenic DI are caused by drugs, especially chronic lithium use. The Case: A 46-year-old man manifested such a disorder 8 months following d-Penicillamine (d-P) therapy for cystinuria. The drug was discontinued and the patient was managed conservatively with high fluid intake, diet low in protein and salt as well as alkalization of urine with Urolyte U to a pH > 7.5. Six weeks later, such side effect disappeared. Our patient had developed such phenomenon: a) without significant liver or renal disease to account for cumulative toxicity, and b) with a conventional dosage range of d-P. Such isolated toxicity indicates inherited a predisposition to this side effect. Conclusion: DI is a potential side effect of d-P therapy that is nephrogenic in site, transient in prognosis and an isolated phenomenon likely to reflect genetic predisposition.