Abstract: PUB166
Kidney Biopsy During Active Pulmonary Embolism: When ANCA Positivity Is Not Enough and Venous Thromboembolism Is the Disease Declaring Itself
Session Information
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Choppala, Pratheek, Corewell Health William Beaumont University Hospital, Royal Oak, Michigan, United States
- Abu-Khaled, Jamal, Corewell Health William Beaumont University Hospital, Royal Oak, Michigan, United States
- Pothugunta, Krishna, Corewell Health William Beaumont University Hospital, Royal Oak, Michigan, United States
- Garlapaty, Vamshi K., Corewell Health William Beaumont University Hospital, Royal Oak, Michigan, United States
Introduction
ANCA-associated vasculitis (AAV) with concurrent VTE creates two emergencies: biopsy hemorrhage risk versus irreversible nephron loss from untreated RPGN. Multisystem disease was misattributed to pneumonia; biopsy revealed histology that changed management.
Case Description
45M, no autoimmune history, bilateral DVT and PE. Two months prior: hemoptysis, purpura, polyarthralgias, 30-lb weight loss — attributed to pneumonia twice.
Cr 1.84 (baseline 0.76), Hgb 8.0. UA: 3+ hematuria, PCR 0.93. C-ANCA 1:320; PR3-ANCA >160. Anti-GBM negative. CT: bilateral GGOs. Heparin started.
Biopsy (heparin held 6h/resumed 4h; no hemorrhage): 9/13 crescents, fibrinoid necrosis, IF all negative, no deposits. ANCA crescentic GN, pauci-immune; Berden crescentic class.
Methylprednisolone 500mg ×3d; rituximab 1g+cyclophosphamide 750mg day 4; prednisone 80mg; apixaban. Discharge Cr 2.12.
Discussion
Systemic synthesis. Hemoptysis, hematuria, purpura, and weight loss in isolation delayed diagnosis. A unified assessment would have prompted ANCA testing earlier.
Biopsy during anticoagulated VTE is feasible and indispensable. Major bleeding <1% (Corapi CJASN 2012; KDIGO 2024). Tissue confirmed pauci-immune histology and Berden crescentic class, predictor of renal survival, justifying RTX+CYC. Serology cannot provide this. PEX deferred per PEXIVAS 2020.
Novel: VTE in AAV is the disease's procoagulant phenotype. NET formation and tissue factor complete Virchow's triad. VTE risk is 7-22x higher in active AAV. Immunosuppression treated nephritis and thrombophilia. Anticoagulation: the bridge. Immunosuppression: the destination.
Acknowledgment
The author thanks Dr Jamal Abukhaled, Dr Krishna S. Pothugunta, and Dr Vamshi Garlapaty for their mentorship, clinical guidance, and feedback on this case presentation. Writing assistance was provided by Claude (Anthropic, claude-sonnet-4-6); the author takes full responsibility for all content.