Incidence and features of dual anti-GBM-positive and ANCA-positive patients.

AIMS: Goodpasture's syndrome, glomerulonephritis and pulmonary haemorrhage, may be due to a variety of causes. Rarely, patients with Goodpasture's syndrome present with both anti-glomerular basement membrane (GBM) and antineutrophil cytoplasmic antibody (ANCA). The aim of this report was to determine the incidence, clinical features, management and outcomes of patients presenting with concurrent ANCA and anti-GBM disease in Auckland.
METHODS: Potential patients were identified by an electronic search of serology for ANCA and anti-GBM antibody, diagnostic renal biopsy, or in-hospital admissions using ICD9 and ICD10 codes between 1998 and 2008. A retrospective case-note review of all potential cases was performed.
RESULTS: Six cases were identified: two women and four men. The incidence was estimated at 0.47 cases per million people per year. The mean age of presentation was 59 years (range 25-85 years). One patient was a smoker and two patients were ex-smokers. All subjects were anaemic, had haemoptysis and an abnormal chest X-ray at presentation. The mean creatinine at presentation was 225 µmol/L (range 126-406 µmol/L); all patients had haematuria and proteinuria. All patients received corticosteroids and cyclophosphamide. Two patients were not plasma exchanged and died. Four patients received plasma exchange and are alive. One patient had a clinical relapse 6 years after their initial presentation and is on renal replacement therapy.
CONCLUSION: Concurrent ANCA and anti-GBM disease is rare. The mortality rate is high. Aggressive immunosuppression with steroids, cyclophosphamide and plasma exchange can induce remission and preserve renal function. Long-term monitoring for relapses should occur.