What is anti-GBM disease?
Anti-GBM disease is caused by autoantibodies (usually IgG) directed against the alpha-3 chain of collagen IV — the structural protein in the basement membranes of:
- Kidney glomeruli (capillary filters)
- Lung alveolar capillaries
The antibodies bind, trigger complement, and recruit neutrophils that destroy the basement membrane.
In Kidneys
- Rapidly progressive glomerulonephritis with crescent formation
- Can go from normal creatinine to dialysis within 1-2 weeks
- Often the only manifestation in older adults
In Lungs
- Alveolar haemorrhage — coughing blood, breathlessness, anaemia
- Smokers and those exposed to hydrocarbons (paint thinners, fuels) have much higher lung disease
- In non-smokers, lung disease is much less common
KIDNEY + LUNG = 'Goodpasture's syndrome' (historical eponym). Kidney only = anti-GBM disease.
Who Gets It
- Very rare: ~1 per million per year in UK
- Bimodal age peaks: 20-30 (often with lung involvement) and 60-70 (often kidney only)
- Slight male predominance in young; equal in older
- HLA-DR15 strongly associated
- Often follows viral infection, influenza, or environmental trigger
- Up to 30% are also ANCA positive ('double-positive') — important for prognosis
Symptoms and emergency diagnosis
Renal Symptoms
- Visible blood in urine
- Frothy urine (proteinuria)
- Falling urine output
- Ankle swelling
- Fatigue, breathlessness (from anaemia or fluid)
- Rising creatinine on routine blood test
Lung Symptoms
- Cough
- Breathlessness
- Haemoptysis (coughing blood) — can be massive
- Iron deficiency anaemia from chronic alveolar bleeding
- Crackles on examination
- Diffuse infiltrates on chest X-ray/CT
INVESTIGATIONS (URGENT — same day):
- ANTI-GBM ANTIBODY blood test
- ANCA (PR3, MPO)
- Creatinine, eGFR (often rising rapidly)
- Urine ACR, microscopy (red cells, red cell casts)
- FBC (anaemia)
- Coagulation
- Chest X-ray ± CT
- Bronchoscopy if pulmonary haemorrhage suspected
Kidney Biopsy
- Crescentic glomerulonephritis (often 80-100% of glomeruli have crescents)
- Linear IgG deposition along glomerular basement membrane on immunofluorescence (pathognomonic)
- Should be performed urgently — do NOT delay treatment waiting for biopsy
TREATMENT STARTS ON SUSPICION — confirmed anti-GBM antibody + crescentic GN clinical picture is enough.
Kidney Vitality is a daily multivitamin developed by a UK Consultant Nephrologist using renal nutrition principles. It contains no added potassium, magnesium, phosphorus or iron, and no herbal blends. See the formulation.
Treatment — combined and urgent
STANDARD REGIME — all three started together:
1. Plasma Exchange (Plex)
- Daily for 14 days or until anti-GBM antibody undetectable
- Removes circulating antibody
- 4L per session, fresh frozen plasma or albumin replacement
- Needs central line
2. Corticosteroids
- IV methylprednisolone 500-1000 mg ×3 days
- Then oral prednisolone 1 mg/kg/day
- Slow taper over 6 months
3. Cyclophosphamide
- Oral 2 mg/kg/day (max 200 mg)
- Continue for 3 months total
- Then stop — disease rarely relapses
- Bone marrow monitoring (weekly FBC)
- Reduce dose if eGFR < 30 or age > 60
Adjuncts
- Co-trimoxazole 480 mg daily (PCP pneumonia prophylaxis)
- Bone protection (calcium, vitamin D, bisphosphonate)
- PPI gastric protection
- Antifungal prophylaxis with high-dose steroids
- MESNA with cyclophosphamide (bladder protection)
- Antiemetics
- Stop smoking IMMEDIATELY — smoking dramatically worsens lung disease
- Avoid hydrocarbon exposure
Newer
- Rituximab considered in some cases (especially if cyclophosphamide contraindicated)
- Imlifidase (IdeS) — cleaves circulating IgG; under study
- Emergency haemodialysis if needed (does not preclude treatment)
Prognosis and what to expect
KIDNEY OUTCOMES depend on presentation:
GOOD prognosis if:
- Creatinine < 500 µmol/L at start
- Not yet dialysis-dependent
- Few crescents on biopsy (< 50%)
- No oliguria
→ 80-90% kidney recovery
POOR prognosis if:
- Creatinine > 500 at start
- Dialysis-dependent at presentation
- > 85% crescents on biopsy
- Oliguria/anuria
→ < 10% recover off dialysis
In the latter group, current guidance suggests NOT starting heavy immunosuppression unless lung haemorrhage is also present (no kidney benefit, high infection risk). Always individualised.
Lung Outcomes
- Usually fully recover with treatment
- Lifelong small reduction in lung function tests
- Stop smoking is non-negotiable
Relapse
- Very rare unlike ANCA vasculitis (< 3%)
- Lifelong follow-up still recommended
- Annual anti-GBM, urine, creatinine, BP
Transplant
- Wait 6-12 months after anti-GBM becomes negative
- Living donor or deceased donor
- Rarely recurs in graft
- Outcomes excellent — equivalent to other causes
Living with anti-GBM disease
EARLY POST-TREATMENT (months 0-6):
- Frequent clinic visits — weekly to monthly
- Watch for infection on immunosuppression
- Recovery often slow; emotional support important
- Physiotherapy and rehabilitation
- Patient organisations: Kidney Care UK
LATER (year 1 onwards):
- 3-6 monthly nephrology review
- Annual anti-GBM antibody
- BP, urine ACR, creatinine
- Lifelong avoidance of smoking, hydrocarbon exposure
- Cardiovascular risk factor optimisation
- Address mental health — this is a traumatic illness
If Dialysis-dependent
- Decisions about transplant
- Modality choice (HD vs PD)
- Holiday dialysis planning
- Diet and lifestyle adjustments
- See our Preparing for Dialysis and Dialysis Diet guides
Family
- Not inherited (sporadic)
- Family screening not needed
If You Smoke Or Work With Solvents
- Smoking quintuples lung disease risk in anti-GBM
- Hairdressers, painters, mechanics, petrol station workers — discuss occupational exposure with team
- Even cured patients should avoid these triggers lifelong
