[Neutrophil anticytoplasmic antibodies in a patient with Wegener's granulomatosis: therapeutic implications of its detection and relation to clinical activity].

The case of a patient with a multisystemic process characterized by polyarthritis, hemoptysis, leucocytoclastic vasculitis, renal failure and ulcerated lesions in the palate and nasal bone is reported. The existence of antineutrophil anticytoplasmic antibodies (cytoplasmatic pattern) was proven by indirect immunofluorescence with an initial serum titration of 1:1.600. Detection of these antibodies permitted the establishment of immunosuppressive treatment when the clinical situation of the patient was considered serious (pulmonary hemorrhage with progressive diminution of the hematocrit). Four days after the initiation of treatment the histopathological results of the palate and nasal mucous biopsies were received and were compatible with Wegener's granulomatosis. Serial determination of the titers of these antibodies demonstrated a close correlation with the clinical biological activity of the process. Indeed, 3 days after initiation of the immunosuppressive treatment the concentration of the same had reduced to half, something which has not been previously reported. It is concluded that high specificity and sensitivity of antineutrophil anticytoplasmic antibodies with a cytoplasmatic pattern for Wegener's granulomatosis may contribute to the improvement, not only of the diagnosis but also to the prognosis, in permitting the immediate initiation of therapeutic measures when the clinical situation of the patient thus requires.