Abstract: PO1409
A Rare Case of Immunotactoid Glomerulopathy Associated with Rheumatoid Arthritis
Session Information
- Glomerular Diseases: Fibrosis and Extracellular Matrix
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1201 Glomerular Diseases: Fibrosis and Extracellular Matrix
Authors
- Seneriz, Ramon A., Jackson Memorial Hospital, Miami, Florida, United States
- Rodriguez, Juanly N., Jackson Memorial Hospital, Miami, Florida, United States
- Zuo, Yiqin, Jackson Memorial Hospital, Miami, Florida, United States
Introduction
Immunotactoid glomerulopathy (ITG) is a rare disease that is characterized by nephrotic range proteinuria, hematuria, hypertension, and kidney failure. It is most commonly associated with hematologic disorders. Rarely it presents as a polyclonal process and associated with autoimmune disorders such as rheumatoid arthritis (RA).
Case Description
A 50-year-old woman with a medical history of rheumatoid arthritis without treatment who was recently diagnosed with hypertension (174/82 mmHg) with elevated serum creatinine (Scr 2.2mg/dL). She lost follow-up and returned to emergency department 5 months later complaining of worsening edema, fatigue, foamy urine, and joint pain for which she was taking NSAIDs daily. Further workup showed Scr of 3.0 mg/dL, proteinuria (urine protein to creatinine ratio 14 g/g), hematuria (5 RBCs/HPF), positive ANA (1:160), rheumatoid factor (140), and cyclic citrullinic peptide (30.4), negative for ANCA, dsDNA, cryoglobulins, Hepatitis B and C, HIV, SPEP, UPEP, and serum free light chains with normal complement levels.
A renal biopsy showed diffuse thickening of the glomerular basement membranes with focal segmental endocapillary hypercellularity by light microscopy. There is polyclonal IgG-dominant smudgy/chunky capillary loop staining with mesangial extension with lesser IgM and C1q by immunofluorescence and numerous subepithelial deposits and occasional subendothelial deposits, which exhibit a microtubular substructure with hollow cores arranged focally in parallel arrays and measuring 11-72 nm with an average of 34 nm by electron microscopy. A Congo red is negative for amyloidosis.
She was treated with low dose prednisone (10mg/day) for her RA. Upon follow up it was noted her Scr decreased to 1.4mg/dL but nephrotic range proteinuria persisted.
Discussion
ITG is a rare glomerulopathy. Determining the clonality and the underlying etiology is essential for the management. This case is associated with RA and presents as a polyclonal ITG. The exact treatment for this condition is unknown. Will continue following her closely as historically ITG caries a poor renal prognosis.