with ChurgÐStrauss syndrome have circulating ANCA that is usually antimyeloperoxidase.

6.1.9.5 Diagnosis

Diagnosis of ChurgÐStrauss syndrome is based on both pathological and clinical Þndings. Demonstration of necrotizing small-vessel vasculitis and eosinophilic necrotizing intraand extravascular granulomas on biopsy material conÞrms the diagnosis of ChurgÐStrauss syndrome in a patient with compatible multisystem clinical Þndings and laboratory tests (most importantly asthma and peripheral blood eosinophilia) [318, 319, 322Ð327]. Involved tissues more commonly biopsied for diagnosis are lung, skin, and peripheral nerves.

6.1.10Granulomatosis with Polyangiitis (Wegener)

Granulomatosis with polyangiitis (Wegener) is a systemic disease of unknown etiology characterized, as it was originally described, by granulomatous inßammation of the upper and lower respiratory tract, necrotizing vasculitis, and nephritis [327Ð329]. A description of classic pathological Þndings is shown in Table 6.9. Aside from this fulminant, active, generalized, or disseminated form of the disease, an indolent form called limited, initial, or locoregional GPA also may occur [330Ð334]. In the limited form of GPA, the respiratory tract is involved and the

kidneys are spared; chronic hemorrhagic rhinitis, sinusitis, otitis, ulcerations in the oral cavity, nasolacrimal duct obstruction, orbitopathy, conjunctivitis, keratitis, scleritis, or uveitis also may occur [331Ð337]. Pathologically, involved tissues reveal necrotizing granulomatous inßammation and vasculitis. A highly limited form of GPA has been described by our group [338] in patients with only ocular or orbital disease on the basis of a constellation of histopathological Þndings and a positive laboratory test (ANCAs).

Untreated GPA is rapidly fatal, particularly once there is functional renal impairment; onset of renal disease is associated with a mean survival of 5 months, with a 1-year mortality rate of 82% of patients and a 2-year mortality rate of 90% [330]. Therapy with systemic corticosteroids and immunosuppressive agents may induce remission in 93% of patients [337]. It is imperative, therefore, to establish the diagnosis and initiate appropriate treatment as early as possible in the course of the disease.

6.1.10.1 Epidemiology

GPA (Wegener) is a rare disease that typically occurs in patients between 40 and 60 years of age, although presentation at ages ranging from 7 to 75 has been reported [337, 339]. The disease occurs slightly more frequently in men than in women, with a ratio up to 1.5:1 [330, 337, 340]. GPA (Wegener) may affect blacks and Hispanics, but is most commonly seen in Whites [337].