Abstract: SA-PO225
Where’s the Clone? Successful Treatment of Monoclonal Gammopathy of Renal Significance with Type 1 Cryoglobulinemia with Plasma-Cell Directed Therapy
Session Information
- Trainee Case Reports - V
October 27, 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
- Onuchic-Whitford, Ana Claudia, Brigham and Women's Hospital / Massachusetts General Hospital, Boston, Massachusetts, United States
- Klepeis, Veronica E., Massachusetts General Hospital, Boston, Massachusetts, United States
- Allegretti, Andrew S., Massachusetts General Hospital, Boston, Massachusetts, United States
Introduction
Type 1 cryoglobulins are monoclonal immunoglobulins produced by clonal expansion of B cells. They are often associated with an overt hematologic malignancy, but sometimes occur without identification of a monoclonal cell population. We describe a case of type 1 cryoglobulinemia with a rare crystalline morphology on renal pathology and without an evident monoclonal population, that had excellent response to plasmapheresis and plasma-cell directed therapy.
Case Description
A healthy 61 year old woman initially presented with one year of intermittent knuckle swelling in cold weather and bilateral calf pain. She later developed generalized weakness and was admitted with hypertensive emergency, AKI [serum creatinine (SCr) 2.0 mg/dL], edema, livedo reticularis, and blurry vision. Workup was notable for dysmorphic red cells on urine sediment, 2 grams of proteinuria, low complements, normal serum calcium, serum Kappa/Lambda ratio 5.73, IgG kappa M spike, and 2% type I cryoprecipitate. Renal biopsy showed crescentic and necrotizing cryoglobulinemic glomerulonephritis with crystalline morphology of monoclonal IgG1 kappa (see Figure). Bone marrow biopsy showed no clonal cell population. The patient was treated with pulse steroids, plasmapheresis, and maintained on cyclophosphamide, bortezomib and dexamethasone, resulting in rapid improvement of symptoms and SCr to 0.96 mg/dL after 7 weeks.
Discussion
This case illustrates a classical presentation of monoclonal gammopathy of renal significance, where renal damage ensues from cryoglobulin deposition, likely produced by a monoclonal population not detectable by standard testing. Treatment of this hidden population by clonal cell-directed therapy resulted in excellent renal and symptomatic recovery. Additionally, pathology images reveal the assembly of monoclonal immunoglobulins into crystals, a rare variant of cryoglobulinemia.