Kidney Week

Abstract: TH-PO535

A Patient with PLA2R Membranous Nephropathy and “Non-Depletion” After Rituximab

Session Information

• Trainee Case Reports - I
  October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Trainee Case Reports

• 1202 Glomerular Diseases: Immunology and Inflammation

Authors

• Hanna, Wael A., Lehigh Valley Hospital, Breinigsville, Pennsylvania, United States

Wael A. Hanna,

• Duffy, Margaret, Valley Kidney specialists, Allentown, Pennsylvania, United States

Margaret Duffy,

• Saqib, Mohammad N., Valley Kidney specialists, Allentown, Pennsylvania, United States

Mohammad N. Saqib,

Introduction

Rituximab failure in patients with membranous nephropathy with nephrotic syndrome has been described in the literature. We present a case of PLA2R membranous nephropathy who progressed immunologically and did not show evidence of B cell depletion despite use of rituximab.

Case Description

A 62 year-old man with history of hyperlipidemia and hypertension presented with sudden onset lower extremity edema. Labs revealed sCr 1.1 mg/dL, albumin 2.9 g/dL, total cholesterol 235 mg/dL, triglycerides 116 mg/dL, and LDL 132 mg/dL. He had 12.5 grams of protein/24 hour urine collection. ANA, C3, C4, hepatitis panel, serum and urine electrophoresis were all negative/ unremarkable. A renal biopsy was performed which revealed membranous nephropathy that stained positive for PLA2R. Proteinuria and renal function deteriorated despite maximal ARB therapy for >3 months. He was given rituximab infusion 1 g IV every 2 weeks x 2 doses in November 2017. PLA2R antibody titers, CD19 count, sAlb, and sCr were obtained after 2, 4, and 5 months from rituximab therapy as shown in Table 1. Unfortunately given the extent of immunologic progression, we considered treatment failure in this patient and decided against additional rituximab infusions.

Discussion

We present a case with a rare and relatively severe phenotype of PLA2R membranous nephropathy who did not show evidence of B cell depletion and had persistent PLA2R titer progression despite treatment with rituximab. In patients PLA2R membranous nephropathy with nephrotic phenotypes, the use of immunologic biomarkers to ascertain early response is critical in deciding whether to continue or to consider alternative treatments. Novel therapeutic targets such as newer generation anti-CD 20 agents (ie ofatumumab) and plasma cell targets may be helpful in patients with relapsing or rituximab resistant disease. Furthermore, additional biomarkers (eg long-lived plasma cell markers, CD38 and CD138) may be useful while assessing response.

Table 1