Dr. Casper Franssen is a nephrologist and chief of the dialysis unit at the University Medical Center Groningen, the Netherlands. He has a longstanding interest in patients with vasculitis like anti-glomerular basement membrane disease and ANCA-associated vasculitis. His thesis (1999) focussed on the differences in clinical presentation and pathophysiology between patients with anti-proteinase 3 and anti-myeloperoxidase associated vasculitis. Dr. Franssen also has an interest in other rare diseases like atypical HUS and hyperoxaluria and research. His research interests also include acute renal failure and the effect of hemodialysis on the perfusion and function of vulnerable organs like the heart and the brain.