Henoch-Schonlein purpura, sometimes known as HSP, is an autoimmune condition that causes inflammation in the tiny blood vessels of the skin. It is not clear what triggers the condition, but it often appears a few weeks after an upper respiratory infection such as strep or mycoplasma.
HSP is most common in children and the majority of cases appear between ages 2 and 11, but the condition is seen in all ages. Adult Henoch-Schonlein is often more severe than childhood cases. However, the majority of both children and adults recover without long-term effects.
The three primary symptoms of Henoch-Schonlein include a rash that begins as red papules and progresses into deep red or purple spots. The rash is typically seen on the lower legs and buttocks but can appear on other parts of the body including the arms, face and trunk. Abdominal pain and swollen, painful joints make-up the triad of symptoms.
Renal involvement occurs in approximately half of all individuals who have HSP. Small amounts of blood in the urine in a warning sign and tests may also reveal protein in the urine. Most renal issues resolve within six months, but a small number of those afflicted will progress to a renal insufficiency or renal failure over time. Bowel obstruction is a less common symptom but one that is seen in a small number of Henoch-Schonlein cases.
Often dermatologists diagnose Henoch-Schonlein purpura simply by observing the triad of symptoms. If other diseases cannot be ruled out, blood tests, urinalysis, skin biopsy and kidney biopsy may be recommended.
There is no specific treatment for Henoch-Schonlein purpura, and the rash typically goes away within four to six weeks. In addition to rest and fluids, your dermatologist may recommend a mild over-the-counter preparation, such as Tylenol or ibuprofen, for discomfort. Blood and urine tests may be done periodically for several months to monitor kidney function.