Enfermedad renal por depósito idiopático de cadenas livianas: Caso clínico / Kidney involvement in idiopathic light chain disease: Report of one case

ABSTRACT

Idiopathic Light Chain disease (ILCD) is a systemic disease characterized by a deposit in different organs of light chain monoclonal immunoglobulins, produced by an abnormal clone ofB cells. It is usually found in the course ofa plasma cell dyscrasia and in other lymphoproliferative alterations; however it may occur in absence of any hematologic disease and is denominated as idiopathic. We report a 51-year-old mole admitted to the hospital due to anasarca. Laboratory evaluation showed a serum creatinine of 1.4 mg/dl, a serum albumin of1.6 g/dl, a serum cholesterol of 687 mg/dl and a proteinuria of 5.3 g/day Light chains with a predominance of a monoclonal component were identified in urinary proteins by electrophoresis and kappa chains were identified by immunofixation. A renal biopsy showed a diffuse nodular glomerulopathy with a 35% tubular atrophy and interstitial sclerosis. Electrón microscopy confirmed light chain deposition. The bone marrow biopsy showed a myeloid hyperplasia. Thepatient was initially treated with methylprednisolone and plasmapheresis with a reduction in serum creatinine and disappearance of urinary kappa component. Albuminuriapersisted and a malnutrition-inflammatory complex syndrome was diagnosed. Hemodialysis with ultrafiltration was started along with cyclophosphamide. Thepatient receivedhemodialysisforsixmonths and continued with methylprednisolone.