133 Hydroxychloroquine-Induced Lipidosis: Boon for Lupus Nephritis Becomes Bane

Abstract

HYDROXYCHLOROQUINE-INDUCED LIPIDOSIS: BOON FOR LUPUS NEPHRITIS BECOMES BANE Nidhi Jindal, Fotios Koumpouras, Teresa McHale, Sheldon Bastacky, Kelly Liang; University of Pittsburgh, Pittsburgh, PA, USA Hydroxychloroquine (HCQ) is commonly used to treat systemic lupus erythematosus (SLE) and lupus nephritis (LN). We report an interesting case of HCQ-induced lipidosis that was clinically thought to represent worsening LN. A 24 year old Caucasian male with LN class IV-G diagnosed on renal biopsy in 2007 was treated initially with cyclophosphamide (CYC) for 6 months and high-dose steroids followed by tapering prednisone. He was started on mycophenolate mofetil (CellCept) in Feb 2008 along with prednisone and HCQ. In Sept 2008, 24-h urine protein was 2.8 g/day. He had a flare of LN in May 2009 treated with CYC and Solu-Medrol, and he required hemodialysis until July 2009. Renal function was normal until Sept 2009 when creatinine rose to 1.4 mg/dl. In Oct 2009, urine protein increased to 7.8 g/day, and he had foamy urine, abdominal pain, nausea, and vomiting. Due to suspected LN flare or onset of class V LN, CellCept was increased from 1 g to 1.5 g orally twice daily. A renal biopsy revealed no evidence of immune-mediated renal disease, making progression of LN unlikely. Rather, it showed mesangial infiltration by foamy macrophages with lamellated lysosomal inclusions (myeloid bodies), and subendothelial deposits of lipoid material, consistent with HCQ-induced lipidosis. Fabry’s disease was excluded by normal serum alpha-galactosidase A level of 0.192 U/L (normal range 0.075-0.457 U/L). HCQ was discontinued, and he recovered normal renal function with proteinuria decreasing to 0.83 g/day in Nov 2009 and 0.38 g/day in Feb 2010. Rarely, HCQ may cause morphological abnormalities that mimic Fabry’s disease and often presents with similar clinical manifestations. It can erroneously be interpreted as either progression of LN or Fabry’s disease, and renal biopsy is useful in diagnosis. Knowledge of the rare occurrence of HCQ-induced lipidosis is important in the management of LN patients, and it must be considered in SLE patients presenting with worsening renal function and proteinuria. Withholding HCQ is the recommended treatment and can lead to remarkable improvement of renal function and proteinuria.