Churg-Strauss syndrome Churg-Strauss syndrome (CSS) is a granulomatous small-vessel vasculitis. The cause of this allergic angiitis and granulomatosis is not known, but autoimmunity is evident with the presence of hypergammaglobulinemia, increased levels of immunoglobulin E (IgE), and perinuclear-staining (p)-ANCA. The diagnosis relies on biopsy evidence for vasculitis and at least 4 criteria among the following: moderate to severe asthma, blood eosinophilia (at least 10%), and nonfixed pulmonary infiltrates with extravascular eosinophils on biopsy [115] . Twenty-nine pediatric cases have been reported so far in the literature, with lung involvement in 72% of [116] . Anti-glomerular basement membrane disease Goodpasture syndrome is a rare disease that involves rapidly progressive kidney failure along with lung disease and is characterized by the deposition of anti-GBM antibodies. Several cases have been reported in the pediatric literature. The autoantibodies mediate tissue injury by binding to their reactive epitopes in the basement membranes. This binding can be visualized as the linear deposition of immunoglobulin along the glomerular basement membrane. The principle component of the basement membrane is type IV collagen which can be expressed as 6 different chains, from alpha1 to alpha6. The Goodpasture antigen has been localized to the carboxyl terminus of the noncollagenous domain of the alpha3 chain of type IV collagen. The anti-GBM antibody can usually be found in serum [117] . Strong evidence exists that genetics play an important role. Patients with Goodpasture disease have an increased incidence of HLA-DRB1 compared to control populations [118] .