Abstract: TH-PO620

An Unusual Case of Presumed Lecithin-Cholesterol Acyltransferase Inhibitor

Session Information

Category: Nephrology Education

  • 1302 Fellows and Residents Case Reports

Authors

  • Katout, Mohammad, OSU Nephrology, Columbus, Ohio, United States
  • Fussner, Lynn A, The Ohio State University Wexner Medical Center, Columbus, Ohio, United States
  • Brodsky, Sergey V., OSU, Columbus, Ohio, United States
  • Nadasdy, Tibor, Ohio State University, Columbus, Ohio, United States
  • Ayoub, Isabelle, None, Columbus, Ohio, United States
Background

Lecithin-cholesterol acyltransferase (LCAT) is a glycoprotein produced predominantly by the liver. LCAT binds mainly to HDL particles and contributes to HDL maturation and cholesterol homeostasis. LCAT deficiency is a rare autosomal recessive disease, however an immune-mediated, acquired form has been reported. In both situations lipoprotein deposition in the glomeruli may lead to end stage kidney disease. This case illustrates the challenge of managing acquired LCAT deficiency when the underlying etiology is unclear.

Results

A 27 y old woman transferred to our center for worsening shortness of breath over 2 months. She already received 1g of rituximab and was on prednisone for concerns of an underlying auto-immune disease. Diagnostic work up was significant for AKI, hemolytic anemia, thrombocytopenia, hyperbilirubinemia, high ferritin, low HDL (3mg/dl), + ANA,+ SSA and bilateral pulmonary infiltrates. Kidney biopsy showed lipoprotein deposits in the widened sub-endothelial space with some mesangial and intracellular deposits(see figure). Some features of TMA were noted. Lung biopsy showed NSIP and isolated intravascular foreign material. LCAT activity was checked, but after rituximab infusion and having been on prednisone for 2 weeks, and it was normal. LCAT genetic testing didn’t show sequence variants.
The patient was continued on high dose prednisone. Cytopenia and hyperbilirubinemia resolved. Her HDL level began normalizing (up to 20 mg/dl) and AKI resolved. She had a mild improvement in respiratory symptoms.

Conclusion

Immune-mediated acquired LCAT deficiency may be difficult to diagnose. In this case clues to the presence of an inhibitor of LCAT included response to steroids and negative genetic testing. Confirming an underlying auto-immune disease remains a challenge for future decisions regarding immunosuppressive therapy to prevent further organ damage.