Henoch-Schönlein purpura (IgA vasculitis)
Causes and risk factors
The disease is most common in children aged 4 to 10 years and often occurs after an upper respiratory tract infection. Men and women get ill with the same frequency. In adults, it is less common, but, unlike children, it can have a chronic course.
This is a disease in which there is inflammation of small blood vessels (vasculitis) due to the accumulation of immune complexes in their walls (a complex of specific antibodies with the antigen to which it is directed). As evidenced by a biopsy of the lesion, the antibody involved is of type IgA.
Which are the symptoms?
The disease is characterized by the appearance of purple, towering, non-itchy spots on the skin, which emerge mainly on the extremities and in pressure zones. With arthritis, large joints (ankle and knee) are affected with a temporary and migrating nature of pain.
Often there are complaints of abdominal pain (colic) with complications in the form of nausea, vomiting, symptoms of acute abdominal pain.
Kidney damage may appear when other manifestations have already disappeared. It is characterized by the presence of traces of blood and protein in the urine, and, very rarely, impaired renal function.
How is it diagnosed?
How is it treated?
In children, the disease ceases independently and does not require special treatment. In adults, kidney damage, if chronic, may require steroid or possibly immunosuppressive therapy.