# Diffuse Alveolar Haemorrhage and Goodpasture Syndrome > Diffuse alveolar haemorrhage and Goodpasture syndrome for NEET-PG Medicine: anti-GBM antibodies, renal biopsy, lavage findings and plasma exchange. - Canonical URL: https://prepelephant.com/topics/neet-pg/medicine/diffuse-alveolar-haemorrhage-and-goodpasture-syndrome - Exam / course: NEET-PG · Subject: Medicine - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-08 - Last updated: 2026-10-08 - Reference basis: Harrison's Principles of Internal Medicine; Oxford Handbook of Clinical Medicine; KDIGO Clinical Practice Guideline for Glomerulonephritis - How to cite: "Diffuse Alveolar Haemorrhage and Goodpasture Syndrome", PrepElephant, https://prepelephant.com/topics/neet-pg/medicine/diffuse-alveolar-haemorrhage-and-goodpasture-syndrome ## Direct answer Diffuse alveolar haemorrhage is bleeding into the alveolar spaces that causes haemoptysis, falling haemoglobin and diffuse infiltrates, and Goodpasture syndrome is the anti-glomerular basement membrane antibody disease that produces it with rapidly progressive glomerulonephritis. Diagnosis rests on anti-GBM antibody testing and a renal biopsy showing linear immunoglobulin G along the basement membrane, since lung and kidney are often affected together. Treatment is urgent plasma exchange with high-dose corticosteroids and cyclophosphamide, and dialysis decisions depend on the degree of renal recovery. ## What you must remember - **Diffuse alveolar haemorrhage:** haemoptysis, anaemia and diffuse alveolar opacities on imaging; bronchoalveolar lavage returns progressively bloodier fluid on serial aliquots. - **Anti-GBM target:** antibodies attack the alpha-3 chain of type IV collagen in the non-collagenous NC1 domain of the basement membrane. - **Renal picture:** rapidly progressive glomerulonephritis with crescents and linear immunoglobulin G deposition on immunofluorescence. - **Triggers and genetics:** smoking and hydrocarbon exposure precipitate disease, and an HLA-DR15 association is described. - **Plasma exchange:** removes circulating antibodies and is most useful when started before dialysis is required, alongside methylprednisolone and cyclophosphamide. - **Other causes:** ANCA vasculitis, systemic lupus, coagulopathy and idiopathic pulmonary haemosiderosis must be excluded before labelling disease as Goodpasture. - **Monitoring:** anti-GBM titres and creatinine guide treatment duration, and haemoglobin is monitored and transfused as needed during active bleeding. ## A pathway from haemoptysis to diagnosis A 27-year-old smoker presents with two weeks of haemoptysis, breathlessness, a haemoglobin of 8 g/dL and rising creatinine, with red cells and casts in the urine. The chest CT shows bilateral ground-glass shadowing. 1. **Confirm alveolar bleeding:** bronchoscopy with lavage shows progressively bloodier aliquots, and haemosiderin-laden macrophages appear later. 2. **Check serology:** a positive anti-GBM assay supports the diagnosis. 3. **Confirm on the kidney:** a kidney biopsy with linear immunoglobulin G deposition confirms it, so a lung biopsy is rarely needed. 4. **Start treatment without waiting:** pulse methylprednisolone, daily plasma exchange and cyclophosphamide, with smoking cessation and transfusion support. 5. **Weigh dialysis:** if the kidney has already reached dialysis-level failure with little reversible damage, plasma exchange offers less benefit, and the team weighs ongoing renal replacement against recovery. A normal chest film would not exclude the diagnosis, because the lungs can look clear early. Diffusing capacity for carbon monoxide is often raised during active bleeding, because haemoglobin in the alveolar spaces takes up the gas. It is therefore a clue to bleeding rather than a measure of lung damage. ## Where the exam tries to catch you Examiners build these traps into stems that mix haemoptysis with renal failure. - **Trap:** picking anti-MPO from a stem that offers both anti-GBM and anti-MPO options. — **Correct:** anti-MPO and anti-PR3 belong to ANCA vasculitis such as microscopic polyangiitis or granulomatosis with polyangiitis, which gives pauci-immune glomerulonephritis without linear deposits. - **Trap:** treating with plasma exchange alone. — **Correct:** the right answer always combines plasma exchange with immunosuppression. - **Trap:** reading an IgA-dominant glomerulonephritis with haemoptysis as anti-GBM disease. — **Correct:** that pattern points to IgA vasculitis or other IgA disease instead. - **Trap:** missing a systemic cause in a young patient with haemoptysis and renal failure. — **Correct:** check for systemic lupus, since lupus nephritis and diffuse alveolar haemorrhage can coexist. Goodpasture disease is the answer when the stem mentions linear staining and smoking as a precipitant. ## Frequently asked questions ### Which antibody confirms Goodpasture syndrome? Anti-glomerular basement membrane antibody, detected by ELISA, confirms Goodpasture syndrome, and its target is the alpha-3 chain of type IV collagen. A renal biopsy showing linear immunoglobulin G along the basement membrane supports the diagnosis when serology is equivocal. ### What does bronchoalveolar lavage show in diffuse alveolar haemorrhage? Bronchoalveolar lavage in diffuse alveolar haemorrhage returns progressively bloodier fluid on serial aliquots, which distinguishes alveolar bleeding from a single airway source. Haemosiderin-laden macrophages appear later, as a marker of repeated haemorrhage. ### Why is plasma exchange used in anti-GBM disease? Plasma exchange removes circulating anti-GBM antibodies quickly, and it is usually combined with corticosteroids and cyclophosphamide. Its benefit for kidney recovery is greatest when started before dialysis becomes necessary. ### Can ANCA-associated vasculitis cause diffuse alveolar haemorrhage? Yes, microscopic polyangiitis and granulomatosis with polyangiitis both cause diffuse alveolar haemorrhage, but the antibodies are anti-MPO or anti-PR3 rather than anti-GBM. Serology and the pattern of renal biopsy findings separate the two diagnoses.