Churg-Strauss syndrome, also known as allergic granulomatosis, is an autoimmune disorder characterized by accumulated antibodies, inflammation of blood vessels, and abnormal clustering of white blood cells. An allergic reaction or asthma may precede the syndrome’s development by several years. Although Churg-Strauss syndrome patients may have a prior history of pulmonary disease, the syndrome tends to impair kidneys or other organs or to cause nerve damage in affected areas. Diagnosis is difficult because early symptoms mimic common flu. Lung tissue infiltrations (short-term or persistent), fever, and weight loss are often initial signs. Prompt diagnosis and treatment (with corticosteroids) increase a patient’s chances of resuming a normal life. Onset typically occurs from 15-70 years of age, and the disease affects both males and females.