Abstract: PO1506
Anti-LRP2 Nephropathy in a Patient with Chronic Lymphocytic Leukemia
Session Information
- Glomerular Diseases: The Excitement of Clinical Cases
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Tran, Derek, St Mary Medical Center, Langhorne, Pennsylvania, United States
- Yang, Chien-Wen, Penn Medicine, Philadelphia, Pennsylvania, United States
- Israni, Avantika, St Mary Medical Center, Langhorne, Pennsylvania, United States
- Geara, Abdallah Sassine, Penn Medicine, Philadelphia, Pennsylvania, United States
- Lee, Al Jonathan, St Mary Medical Center, Langhorne, Pennsylvania, United States
Introduction
Anti-LRP2/anti-Brush Border nephropathy is a newly identified autoimmune tubulointerstitial nephritis triggered by circulating antibodies to low-density lipoprotein receptor-related lipoprotein 2 (LRP2). We present a case of anti-LRP2 nephropathy in a patient with chronic lymphocytic leukemia (CLL).
Case Description
A 74-year-old Caucasian male patient known to have CLL presented following a fall with a forearm laceration. At presentation, he had acute renal failure (sCr of 5.04 mg/dL) and severe thrombocytopenia (platelets of 11,000/u). Additional evaluation showed positive ANA and p-ANCA. The patient had proteinuria of 1754 mg/g of creatinine. The kidney biopsy showed moderate interstitial fibrosis and tubular atrophy involving 30-40% of the renal cortex. The tubular epithelium showed reactive-appearing nuclei as well as cytoplasmic thinning with loss of the proximal tubular brush border. Immunofluorescence showed IgG (3+) and C3 (3+) for the glomeruli capillary and the TBM. There was focal staining of the brush borders by IgG with positive LRP2 stain in the TBM. Electron microscopy revealed numerous subepithelial electron-dense deposits. The serum anti-LRP2 antibody titer was 1:100. The patient was started on dexamethasone and rituximab with improvement of the thrombocytopenia. Plasmapheresis was prescribed for 5 sessions, the creatinine continued to worsen (sCr of 7.73 mg/dL), and the anti-LRP2 titer did not improve. The patient is being transitioned to renal replacement therapy.
Discussion
The mechanism that links the ABBA disease with lymphoproliferative disease is still unknown. The current reported cases suggest an association between direct lymphoma renal infiltration, progression of the lymphoproliferative disease and the presence of the ABBA disease. However, in our reported case, the patient’s underlying CLL was stable without evidence of renal infiltration. The poor response to treatment in this case is consistent with the poor outcomes of many anti-LRP2 reported cases. The renal biopsy on this patient also showed membranous glomerulonephritis. We presented a case with anti-LRP2 nephropathy/ABBA disease with concurrent CLL without evidence of kidney infiltration which responded poorly to immunosuppression therapy. The prognosis of ABBA associated paraneoplastic syndrome with underlying CLL warrants future investigation.