Abstract: TH-PO094

IgA Dominant Membranoproliferative Glomerulonephritis

Session Information

Category: Glomerular

  • 1004 Clinical/Diagnostic Renal Pathology and Lab Medicine

Authors

  • Andeen, Nicole K., University of Washington, Seattle, Washington, United States
  • Troxell, Megan L., Stanford University School of Medicine, Stanford, California, United States
  • Smith, Kelly D., University of Washington, Seattle, Washington, United States
  • Jefferson, J. Ashley, University of Washington, Seattle, Washington, United States
  • Akilesh, Shreeram, University of Washington, Seattle, Washington, United States
  • Alpers, Charles E., University of Washington Medical Center, Seattle, Washington, United States
  • Finn, Laura S., University of Washington / Seattle Children''s Hospital, Seattle, Washington, United States
  • Higgins, John Patrick, Stanford University, Stanford, California, United States
  • Kambham, Neeraja, Stanford Medical Center, Stanford, California, United States
  • Najafian, Behzad, University of Washington, Seattle, Washington, United States
  • Nicosia, Roberto F., VA Puget Sound HCS, Seattle, Washington, United States
Background

IgA dominant membranoproliferative glomerulonephritis (MPGN) has morphologic and clinical features distinct from IgA nephropathy, lupus, and IgA dominant infection related glomerulonephritis. We sought to better understand the clinical and pathologic characteristics of this disease.

Methods

Native kidney biopsies from 2000 through 2016 with IgA dominant deposition by IF and diffuse MPGN features were retrospectively identified. Cases with only focal or segmental MPGN features, exudative features, prominent subepithelial deposits, other significant nephropathies, or findings of Henoch Schonlein purpura were excluded.

Results

25 biopsies from 21 patients were identified from 5 institutions. The cases were subclassified into two groups: 1) patients without known underlying medical conditions (idiopathic, n=12) and 2) patients with significant gastrointestinal disease or cirrhosis from various etiologies (GI, n=9). The idiopathic group consisted of 9 men and 3 women, with a median age of 38 (range 11-68) years, who typically presented with nephrotic range proteinuria, hematuria, mild renal insufficiency, normal lupus serologies and serum complement levels, and no history of bacterial infection. At a median time of 3 years, 7 had available follow-up. Two progressed to end stage kidney disease, one of whom had recurrent IgA dominant glomerulonephritis in the allograft less than one year post transplant; two had persistent disease with increasing chronic features on repeat biopsy, and three had persistent renal insufficiency and/or proteinuria. From the GI group, follow up was available for 7 patients. At a median time of 2 months after biopsy (range 9 days – 13 months), 6 died and the 7th became dialysis dependent.

Conclusion

IgA dominant MPGN represents a rare but distinct pathologic entity that occurs as an idiopathic form or in association with significant gastrointestinal disease or cirrhosis. The idiopathic form has a poor prognosis, with persistent or progressive disease despite immunosuppressive therapy and recurrence post-transplant. The GI-associated form is associated with death or renal failure within a year of biopsy due to underlying complex medical conditions. Recognition of IgA dominant MPGN may help better define prognostic factors and therapeutic interventions.