Symptoms of small vessel vasculitis are related to the affected vessels and commonly include fever and malaise. Vasculitis is characterized by blood vessel walls with inflammation, which can lead to decreased blood flow and vascular obstruction. Small vessel vasculitis is mainly classified into antineutrophil antibody (ANCA)-associated vasculitis and immune complex small vessel vasculitis. Most patients with ANCA-associated vasculitis have systemic symptoms, such as fever, arthralgia, myalgia, malaise, loss of appetite, weight loss and other systemic symptoms; the skin and mucous membranes are most often involved, manifested by oral ulcers, rash, purpura; common manifestations of the eye, such as conjunctivitis, keratitis, etc.; there can also be a cough, headache, confusion, convulsions, hematuria, angina pectoris, abdominal pain and so on. Immunocomplex small vessel inflammation can be manifested as fever, edema, oliguria, hematuria, proteinuria, hemoptysis, etc. There can also be abdominal distension, nausea and other digestive symptoms. When the above symptoms should be taken seriously, it is recommended to go to the hospital in a timely manner, to clarify the cause of the disease, and follow the doctor’s instructions to standardize the treatment.