Churg-strauss syndrome in the pediatric age group.

The rate of reporting of childhood Churg-Strauss syndrome (CSS) has increased lately because of either increased awareness to the disease or a real increase in incidence. It is defined as one of the antineutrophil cytoplasmic antibody-associated vasculitides, but the antineutrophil cytoplasmic antibody positivity is less reported in pediatric cases. The cause of CSS remains unknown. Several lines of evidence suggest genetic predisposition, which may entail inherited tendency to dysregulation of the cellular immune system. With the addition of leukotriene receptor antagonists to the treatment regimen of asthma, an association to CSS was presumed. However, the nature of this relationship remains to be elucidated. In addition, some environmental factors seem to provoke transient effects that resemble the disease. Patients' symptoms are defined by various degrees of eosinophilic inflammation and necrotizing vasculitis, which may affect any organ. Three clinical stages have been described in the clinical evolution of CSS: prodromal phase involving allergic rhinitis and asthma (usually without family history of atopy), a second phase that involves peripheral eosinophilia and eosinophilic tissue infiltration, and the hallmark of the final phase is systemic vasculitis. Pulmonary disease is a central feature of pediatric CSS, but other manifestations include skin lesions, testicular pain, hypertension, seizures, and nephropathy. More subtle presentations in children include cervical lymphadenopathy, acute abdominal pain, deep venous thrombosis, oral ulceration, multiple colonic ulcers, chorea, bilateral optic neuropathy, and retinal artery occlusions. Churg-Strauss syndrome patients usually respond well to corticosteroid therapy. Several trials reported additional benefit from cyclophosphamide, azathioprine, and methotrexate, whereas the therapeutic effects of etanercept, plasma exchange, and intravenous immunoglobulin therapy are controversial. The relapse rate is approximately 25% to 30%, but corticosteroids have significantly increased survival, which now approaches greater than 75% at 5 years. However, there is limited information about survival or long-term outcome in childhood.