A RARE PRESENTATION OF CONCURRENT ANTI-GBM DISEASE AND IGA NEPHROPATHY: A CASE REPORT
Dr Bryony Beal1, Dr Jason Chen2, Dr Elaine Phua1, Dr Yvonne Shen1
1Department of Renal Medicine, Royal North Shore Hospital, Sydney, Australia, 2Department of Anatomical Pathology, Royal North Shore Hospital, Sydney, Australia
Background: Anti-GBM disease is a rare glomerulonephritis, often characterised by rapidly progressive crescentic renal disease. Whilst this condition has been noted to co-exist with other renal pathologies, namely ANCA vasculitis and membranous nephropathy, cases of concurrent anti-GBM and IgA nephropathy are rare. These patients appear to have a milder phenotype with improved prognosis. Herein we present an additional case of this rare dual pathology.
Case Report: A 50-year-old woman of Asian heritage presented with microscopic haematuria, macroalbuminuria and preserved renal function. Initial renal biopsy revealed mesangial expansion and hypercellularity, with immunofluorescence consistent with IgA nephropathy. She was commenced on anti-proteinuric therapy. On follow up, her serum creatinine rose from 70mmol/L to 117mmol/L. Repeat renal biopsy demonstrated features of IgA nephropathy, now alongside new cellular and fibrocellular crescents and linear IgG staining of the glomerular capillary wall consistent with anti-GBM disease. Her anti-GBM antibody titre was 43. There was no evidence of pulmonary haemorrhage and she did not require renal replacement therapy. She was commenced on plasma exchange, oral cyclophosphamide and corticosteroids. Her anti-GBM titres rapidly fell and were undetectable by week three. She has clinically stabilised, without further deterioration in renal function, though with persistent proteinuria. Repeat biopsy demonstrated improvement in disease activity.
Conclusion:Whilst IgA nephropathy is the most common glomerulonephritis, anti-GBM disease is rare, and the co-existence of these pathologies is even more uncommon. Concurrent disease, as in our case, appears to portend an improved prognosis in comparison to anti-GBM disease alone, with fewer cases of pulmonary haemorrhage, milder renal manifestations and reduced dialysis dependency. This case adds to the limited literature, providing further insights into this atypical presentation and associated renal outcomes.
Biography:
Dr Bryony Beal is a Renal registrar currently completing her Nephrology Advanced Training through the East Coast Renal Network, NSW, Australia. She received her medical degree from The University of Newcastle, Australia, and completed her residency and Basic Physician Training through Royal North Shore Hospital, Sydney, with an interest in chronic kidney disease leading her to subsequently pursue a career in Nephrology.