Abstract: TH-PO183

A Case of Collapsing FSGS Presenting with ANCA Positive Pulmonary Renal Syndrome

Session Information

Category: Nephrology Education

  • 1302 Fellows and Residents Case Reports

Authors

  • Bonifant, George C., Icahn School of Medicine at Mount Sinai/St Luke’s-Roosevelt Hospital Center, New York, New York, United States
  • Smith, Steven D., Icahn School of Medicine at Mount Sinai/St Luke’s-Roosevelt Hospital Center, New York, New York, United States
  • El Hachem, Karim, Icahn School of Medicine at Mount Sinai/St Luke’s-Roosevelt Hospital Center, New York, New York, United States
  • Rehman, Mubasshar, Icahn School of Medicine at Mount Sinai/St Luke’s-Roosevelt Hospital Center, New York, New York, United States
Background

Most cases of HIV-negative collapsing FSGS are idiopathic. However, a growing list of disorders, including mixed connective tissue diseases such as Sjogrens syndrome and SLE, are being reported to cause this lesion

Methods

A 22 y/o female with Sjogren’s syndrome and pericarditis presented with dyspnea and cough. She complained of chronic nasal congestion, anosmia, pleurisy, dry mouth and Raynauds. There were basilar rales, facial acne, pale conjunctiva but no edema or arthritis on exam. Serum creatinine was 1.47 mg/dl (0.6 six months prior). Chest x-ray showed bibasilar airspace consolidations. She developed hemoptysis and respiratory failure requiring intubation. Bronchoscopy showed blood throughout the tracheobronchial tree thought due to diffuse alveolar hemorrhage. Urine protein creatinine ratio was 6.8g/g with an active urine sediment: dysmorphic RBCs and RBC casts. Negative serologies: HIV, parvo B virus, dsDNA, anti-GBM, anti-PR3, C3, C4. Positive serologies: anti SSA/SSB, anti-MPO. She received pulse steroids, cytoxan and plasmapheresis for presumed ANCA vasculitis. Creatinine peaked at 3.6 and improved to 2.0mg/dl with treatment. Renal biopsy showed focal and segmental glomerulosclerosis with collapsing features. Electron microscopy showed podocyte foot process effacement and no immune-type electron dense deposits or tubuloreticular inclusions. Outpatient treatment continues with oral prednisone

Conclusion

The patient presented as pulmonary renal syndrome and an active urine sediment with high titer anti-MPO Ab. Suspicion was high for ANCA vasculitis with expected pauci-immune crescentic GN on biopsy. Instead, collapsing glomerulopathy was diagnosed. Collapsing lesions can resemble crescents (pseudocrescents) and our case was reviewed by several renal pathologists to confirm the diagnosis. This challenges the notion that biopsy isn't necessary when pretest probability for pauci-immune glomerulonephritis is high. We propose that this patient's collapsing glomerulopathy is due to her collagen vascular disease (Sjogren's) and is analogous to lupus podocytopathy