[Wegener's granulomatosis: immunologic aspects of diagnosis, etiology and therapy].

Wegener's granulomatosis (WG) is a rare disease, which has, however, been diagnosed more frequently in the past few years. The etiology is unclear; the pathogenesis is only vaguely understood. The association between HLA-DR2 and/or B8 and WG indicates that there is a genetic predisposition. Without treatment WG is said to run a malignant course with a median survival time of approx. 6 months. With immunosuppressive treatment, however, it is said to be possible to induce long-term remission in about 90% of the cases. Our experience only partially confirms these figures from other countries. From the clinical point of view it is particularly important to point out that there are two phases the disease can run through: In one third of the cases WG begins with an initial stage that can last for many years, but generally does not cause any life-threatening complications. This stable phase can lead into the generalized stage. Untreated, the disease, a fulminant WG characterized by a syndrome of rapidly progressive renal failure and/or respiratory insufficiency, now rapidly leads to death. The clinical diagnosis must always be confirmed by biopsy. Whether the newly discovered disease-specific autoantibody will make a histological examination superfluous in the future is not clear, but at the moment it appears rather unlikely. This antibody against intracytoplasmic antigens of cells of the myelomonocytic line (ACPA) is found in only 60% of the cases with WG. ACPA is often demonstrable in the acute generalized phase, but also during instable partial remissions. In contrast, it is only seldom during the initial stage or in full remission. According to this experience it appears clear that we must adapt the treatment of WG to the stage the disease is in. Low-dose cyclophosphamide-cortisone treatment is considered to be a reliable treatment for the acute generalized stage. Whether the fulminant form can be influenced positively by additive (e.g., plasmapheresis) or alternative (e.g., pulse treatment with cyclophosphamide and cortisone) protocols must remain open at present. We must assume that at least the stable phase of the disease (initial stage) can be treated less aggressively. This will only be possible if close-meshed controls can be carried through at a center for vasculitis, where interdisciplinary cooperation (otorhinolaryngology-ophthalmology-general internal medicine) will make it possible to recognize any exacerbation, so often appearing unexpectedly, at an early point, so that the patient is not endangered unnecessarily.