CSS, also known as allergic granulomatosis angiitis, is a systemic vasculitis. CSS is marked by three distinct symptoms: asthma; eosinophilia, evidenced by an excessive number of eosinophils in the blood and tissues; and vasculitis involving the skin, lungs, nerves, kidneys, and other organs. Nerve involvement may also occur in CSS, causing pain, tingling, numbness, and muscle wasting in the hands and feet. Because CSS patients may not show any visible signs of active disease, current methods of monitoring disease progression usually represent a period of extended inflammation and disease activity. Thus, patients may go untreated during a period of undetectable disease when damage might be preventable. This study will use novel scientific methods to identify new biomarkers that can be used to monitor disease activity in CSS patients. These biomarkers may be used to help direct clinical care for CSS patients and assist in future drug development.

Study visits will occur monthly for the first year, then every 3 months thereafter for the remainder of the study. Blood and urine collection will occur at every visit. A physical exam and medical and medication history will occur every 3 months; also, participants will be asked to complete several questionnaires to assess disease activity, health status, and tobacco, alcohol, and drug use. Participants may have additional study visits if a disease flare or disease-related complications occur during the study.