[Apheresis in the treatment of vasculitis]

ANCA-associated vasculitides are a group of inflammatory diseases affecting medium and small vessels with a redundant and hence complex pathogenetic mechanism. Since their first identification, their dismal prognosis has forced researchers to find effective therapies. The prognosis has changed since the advent of immunomodulatory drugs like steroids, cyclophosphamide, azathioprine, mycophenolate mofetil and, more recently, biological drugs. Plasmapheresis in association with immune suppressant drugs has shown beneficial effects in some clinical trials, mostly in dialysis-dependent patients. Apheresis should remove, in a nonselective manner, pathogenetic antibodies like ANCA but also immune complexes, cytokines and inflammatory mediators. A recent meta-analysis took into account 28 randomized clinical trials studying therapeutic interventions in adult vasculitis with renal involvement, six of them scheduling plasmapheresis as adjunctive therapy to immune suppressant drugs. This association significantly reduced the need for dialysis at three (1 trial: RR 0.45, 95% CI 0.24-0.84) and twelve (5 trials: RR 0.47, 95% CI 0.3-0.75) months but not the mortality at one year. We can conclude that plasmapheresis is an effective treatment option for vasculitides with severe renal failure. It can also be considered in case of ineffectiveness of or contraindications to standard treatment.