Henoch-Schönlein purpura (IgA vasculitis): symptoms, causes and recovery

Henoch-Schönlein purpura, abbreviated to HSP, is a condition in which small blood vessels become inflamed. The NHS describes it as affecting the blood vessels and causing a spotty rash, and says it is not usually serious but can sometimes lead to kidney problems.

Doctors now often use the name IgA vasculitis. Kidney Research UK explains that vasculitis is a group of conditions that cause inflammation of the blood vessels, and that IgA vasculitis can happen in people of all ages but is most common in children under 10.

The NHS says HSP is more common in children, though adults can get it too. Kidney Research UK says the kidney risk is higher when the condition happens in adults.

Kidney Research UK explains the mechanism. IgA is an antibody, a protein made by everyone that usually helps protect the lining of the airway, throat and gut. When abnormal versions of IgA are produced, they can become trapped in small blood vessels and cause inflammation. This usually happens after an infection, most commonly in the throat or gut.

When the kidneys are involved it is called IgA vasculitis nephritis, where blood and protein leak into the urine. The sources we read do not describe any way to prevent HSP.

The main symptom, according to the NHS, is a rash with raised red or purple spots that look like small bruises or blood spots. It usually appears on the legs, bottom, tummy, chest or back, and there may be lots of spots or only a few. Some people also have pain or swelling in joints such as the knees and ankles, and tummy pain.

Kidney Research UK adds that children and adults may have an illness before the symptoms appear, and lists the rash on the feet, ankles, back of the legs, buttocks, back and arms; joint pain and swelling, particularly in the ankles, knees and elbows; tummy pain; feeling or being sick; constipation or diarrhoea, with blood or mucus in stool or vomit; and tiredness.

If the kidneys are affected, there may be blood in the urine (visible or found only on a dipstick test), protein in the urine, passing urine less often or in smaller amounts, high blood pressure, and swelling of the eyes, feet and legs.

The NHS says to ask for an urgent GP appointment or get help from NHS 111 if you or your child have a rash that does not fade when a glass is pressed against it, but you do not feel unwell. This could be HSP.

Call 999 or go to A&E if a rash does not fade under the glass and you feel very unwell, for example it hurts to look at bright lights or there is a stiff neck, because this could be something serious such as meningitis. The NHS explains the test: press the side of a clear glass firmly against the skin and check whether the spots can still be seen through it. On brown or black skin, check paler areas such as the palms of the hands and soles of the feet. Do not drive to A&E.

Kidney Research UK says there is no single test for vasculitis. Doctors usually look at the symptoms and blood pressure and do a urine dipstick test to look for blood or protein.

Other tests may include a blood test for IgA, though IgA vasculitis can still be present without a raised level, a skin or kidney biopsy to look for IgA in the tissue, and an ultrasound scan to exclude other kidney causes.

The NHS says there is no treatment for HSP itself. It usually gets better in a few weeks, and you can usually rest at home until you feel better. Paracetamol can ease pain. The NHS says not to take ibuprofen without speaking to a doctor because it could harm the kidneys, and Kidney Research UK also says ibuprofen is best avoided if there are concerns about kidney inflammation.

Kidney Research UK says that in most cases treatment is not needed because symptoms improve without intervention, usually within a month but sometimes longer, with careful monitoring, usually at home, for several weeks until recovery. Some people need to adjust diet or fluid intake or take medicines for high blood pressure or protein loss in the urine, and immune-dampening medicine is sometimes needed for severe symptoms or kidney inflammation.

The NHS says you may need to go into hospital if HSP affects the kidneys, where you may be given strong medicines such as steroids. It says HSP can sometimes be severe and last several months, and that you can get HSP more than once, so you should seek medical advice quickly if the symptoms come back.

The NHS says you will have regular check-ups for 6 to 12 months to check how well the kidneys are working. You will usually be asked to provide a urine sample and have your blood pressure measured at each appointment, which may be at home, at the GP surgery or in hospital.

Kidney Research UK says all patients need urine checks for the first six months after diagnosis, and for longer if symptoms have not fully recovered. Most people make a full recovery and any kidney problems usually settle without treatment, according to the NHS, but there is a small chance of permanent kidney damage (chronic kidney disease), which is why the check-ups matter. Kidney Research UK says 1 to 2 in every 100 children with IgA vasculitis go on to develop kidney failure, and that the figure is higher in adults.

The NHS says HSP cannot spread to others. Your child can go back to school or nursery when they feel well enough, and adults can return to work as soon as they feel up to it.

Neither the NHS nor Kidney Research UK describes a specific diet for HSP. Kidney Research UK says some patients may need to change diet or fluid intake to manage high blood pressure, protein loss in urine or other complications, and that is a decision for the kidney team rather than a general rule.

On the NHS, a non-fading rash is assessed urgently through NHS 111, a GP or A&E. The NHS says the regular urine and blood pressure checks may be done at home, at the GP surgery or in hospital.

The NHS says you may need to go into hospital if HSP affects the kidneys. The sources we read do not describe anything specific that private care adds for HSP; the follow-up checks matter more than the setting.