Abstract: FR-PO625
Monoclonal Tissue ANA as an Initial Clue to Lupus Podocytopathy
Session Information
- Glomerular Diseases: Lupus and Vasculitis
November 04, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1302 Glomerular Diseases: Immunology and Inflammation
Authors
- Guez, Gilad S., LewisGale Medical Center, Salem, Virginia, United States
- Fernandez, Nicole, LewisGale Medical Center, Salem, Virginia, United States
- Elsanjak, Abdelaziz A., LewisGale Medical Center, Salem, Virginia, United States
Introduction
Lupus podocytopathy (LP) is a rare renal manifestation of lupus without immune complex-mediated pathogenesis. By electron microscopy (EM), there is diffuse podocyte foot process effacement (PFPE), without glomerular capillary wall immune complexes. By light microscopy (LM), glomeruli may be normal or may exhibit mesangial hypercellularity or focal segmental glomerulosclerosis (FSGS); however, proliferative lupus nephritis (LN) is absent. LP is currently not included in the LN classification and may not be recognized without careful clinic-pathologic correlation. This case displays the FSGS variant of LP with monoclonal tissue ANA as the first finding of lupus with good treatment response.
Case Description
19-year-old female was admitted for generalized edema. Labs showed anemia, proteinuria (urine protein/Cr=10.3), microhematuria, hypoalbuminemia, and normal renal function.
Renal biopsy LM showed the tip lesion variant of FSGS (Fig. 1A). By IM, there was low level mesangial IgG/IgM staining. Tubular cell nuclei stained for IgG (Fig.1B) with IgG1 heavy chain and kappa light chain restriction. EM showed extensive PFPE (Fig. 1C) and tubuloreticular inclusions (Fig. 1D), but no capillary wall deposits. The findings were suspicious for LP. Serologies were positive for ANA and dsDNA. Skin biopsy showed lupus dermatitis.
She was started on prednisone, tacrolimus and hydroxychloroquine. Prednisone was replaced with mycophenolate mofetil for maintenance, and remission was acheived.
Discussion
The FSGS variant of LP has low rates of remission with steroids alone. This case shows that robust immune suppression may improve prognosis. LP has histologic similarities with minimal change disease and primary FSGS, so clues from the IF/EM and clinical history help in diagnosis. Monoclonal tissue ANA is a rare finding and was helpful in diagnosing LP in this biopsy.
Fig. 1