Pulmonary Renal Syndromes - OnePager Summary Autoimmune ANCA vasculitis (AAV): GPA (granulomatous with polyangiitis), EGPA (eosinophilic granulomatosis w polyangiitis), MPA (microscopic polyangiitis) Anti-basement membrane: Goodpasture Pulmonary Renal Syndromes (PRS) are life-threatening diseases with pulmonary hemorrhage (DAH) & renal failure (glomerulonephritis). Although pulmonary and renal involvement is the defining feature, PRS can affect many organs: • Pulmonary: pulmonary hemorrhage (DAH), asthma in EGPA, tracheal (subglottic stenosis) in GPA, pulmonary nodules, asthma (EGPA) • Renal: (AKI, proteinuria, hematuria) • Inflammatory eye disease: scleritis, uveitis, episcleritis • ENT: sinus, nasal, hearing loss, saddle nose deformity • Cardiac (in EGPA) • Digital ischemia • Cutaneous: palpable purpura 2/2 vasculitis, ulcers, nodules • Neuro: neuropathy, mononeuritis multiplex WORKUP & DIAGNOSIS Labs: • BMP (quantify renal injury), Coags (r/o coagulopathy) • CBC w differential (check eosinophil count for EGPA) • Auto-antibodies: ANCA antibody, Anti-GBM antibody • Urine: UA, Urine protein to creatinine (UPC) ratio • Cardiac: consider BNP, troponin if concern for EGPA • ESR and CRP (non-specific, ESR usually low in anti-GBM) Other tests: • CT chest to evaluate pulmonary involvement • Bronchoscopy: confirm DAH, r/o infection • Echocardiogram for EGPA (↓ LVEF, pericardial effusion) • PFTs (outpatient; increased DLCO after recent DAN) • EMG/NCS for mononeuritis multiplex/neuropathy Diagnosis of PRS: Biopsy (gold standard) or serologies + symptoms (not-optimal but may be necessary) PULMONARY FINDINGS: • AAV or Goodpasture's cause pulmonary capillaritis leading to diffuse alveolar hemorrhage (DAH) • Diffuse ground glass or consolidative opacities with sparing of the lung periphery is typically seen on chest CT. • BAL reveals increasing blood retum in serial lavages and hemosiderin laden macrophages (diagnostic of DAH) RENAL FINDINGS: • U/A: microscopic or gross hematuria, RBC casts, low grade proteinuria • Path: rapidly progressive (crescentic) glomerulonephritis (fibrinoid necrosis, hypercellular glomeruli, & cellular crescents) • IF staining patterns in crescentic GN by Nick Mark MD @nickmmark and Mithu Maheswaranathan MD @MithuRheum #PRS #Pulmonary #Renal #Syndromes #differential #diagnosis #management #treatment
