IgA vasculitis - henoch-schonlein purpura

IgA vasculitis is inflammation of the small blood vessels. It was previously called Henoch-Schönlein purpura, or HSP.

The condition happens when an immune-system protein called immunoglobulin A, or IgA, collects in small blood vessels. The inflamed vessels can leak blood and fluid into nearby tissues.

The most visible sign is a raised purple or red-purple rash, usually on the legs and buttocks. IgA vasculitis can also affect the joints, digestive system, and kidneys.

It is most common in children, but adults can develop it as well. Most children recover fully over several weeks. Kidney involvement deserves careful follow-up because it may cause lasting damage, particularly in adults or people with more severe kidney inflammation.

IgA vasculitis is not contagious. You cannot catch it from someone who has the condition.

Symptoms may begin together or appear several days apart. The rash is often the clearest sign, but joint or abdominal symptoms can start first.

Common features include:

• A raised red or purple rash that does not fade when pressed
• Pain or swelling in the ankles, knees, feet, hands, or elbows
• Cramping or aching abdominal pain
• Nausea, vomiting, or reduced appetite
• Blood or protein in the urine, often found only through testing

The rash is called purpura, meaning bleeding beneath the skin. The spots can feel raised and may look like small bruises. They usually appear symmetrically on both legs or buttocks. They can also affect the arms, trunk, or face.

Joint pain can make walking uncomfortable, especially in younger children. Although the joints may become swollen and painful, IgA vasculitis does not usually cause permanent joint damage.

Abdominal pain can range from mild cramps to severe pain. Inflammation may cause bleeding in the digestive tract, which can lead to red blood in the stool, black stool, or bloody vomit.

Kidney inflammation may not cause obvious symptoms. When symptoms do occur, they can include dark or reddish urine, swelling around the eyes or ankles, passing less urine, or high blood pressure.

Some boys and men develop pain or swelling in the scrotum. This needs prompt assessment because other conditions, including twisting of a testicle, can cause similar symptoms and require urgent treatment.

The exact reason IgA vasculitis develops is not fully understood. It involves an abnormal immune response in which IgA collects in the walls of small blood vessels and triggers inflammation.

The condition often begins after an upper respiratory infection, such as a cold or sore throat. Less often, other infections, medicines, insect bites, or vaccinations have been reported before an episode. This does not always mean that the preceding event caused the condition.

IgA vasculitis is not usually inherited in a simple, predictable way. Having a relative with it does not mean that you or your child will develop it.

Children are affected more often than adults. Adults who develop IgA vasculitis have a greater chance of significant kidney involvement, so kidney monitoring is especially important.

There is no single blood test that confirms every case. Diagnosis is usually based on the typical non-blanching rash together with joint pain, abdominal symptoms, or signs of kidney inflammation.

An assessment may include:

• Examination of the rash, joints, abdomen, and blood pressure
• A urine test for blood and protein
• Blood tests to check kidney function, blood counts, and inflammation
• A stool test if digestive-tract bleeding is suspected

Blood tests can help assess the effects of the condition and rule out other causes, but a normal blood IgA level does not exclude IgA vasculitis.

A skin biopsy may be needed when the rash is unusual or the diagnosis remains uncertain. A small skin sample is examined for inflamed blood vessels and IgA deposits. A kidney biopsy may be recommended if there is substantial protein in the urine, reduced kidney function, or another sign of serious kidney inflammation.

Ultrasound or other imaging may be used for severe abdominal pain. It can look for complications such as intussusception, in which one section of bowel slides into another.

Urine tests and blood pressure checks remain important after the rash improves. Kidney inflammation can appear later and may have no visible symptoms.

Many cases settle without condition-specific treatment. Management focuses on relieving symptoms, watching for complications, and treating kidney or digestive involvement when necessary.

Rest, fluids, and simple pain relief may help during the acute illness. Paracetamol, also called acetaminophen, is commonly used for pain. Anti-inflammatory medicines such as ibuprofen may sometimes help joint pain, but they may be unsuitable if there is kidney involvement, dehydration, stomach bleeding, or another relevant health problem.

A corticosteroid like prednisone or hydrocortisone may be considered for severe abdominal or joint symptoms. Corticosteroids reduce inflammation. They can shorten some symptoms, but routine early use has not been shown to reliably prevent later kidney disease.

Hospital care may be needed for severe pain, an inability to drink, digestive-tract bleeding, kidney problems, or uncertainty about the diagnosis.

If the kidneys are affected, treatment is based on the amount of protein in the urine, kidney function, blood pressure, and biopsy findings when a biopsy is needed. It may include medicines that reduce blood pressure and protein leakage. More serious kidney inflammation may require corticosteroids or other medicines that suppress immune activity under specialist care.

Follow-up usually includes repeated urine tests and blood pressure measurements for several months. People with continuing blood or protein in the urine need longer monitoring, often through a kidney specialist.

Most people do not develop lasting complications. The main long-term concern is inflammation of the kidney filters, known as IgA vasculitis nephritis.

Kidney inflammation can cause persistent blood or protein in the urine, high blood pressure, or reduced kidney function. In a small minority of affected people, it progresses to chronic kidney disease. The risk is higher when there is heavy or persistent protein leakage, impaired kidney function, or severe findings on kidney biopsy.

Digestive complications are less common but may require urgent treatment. They include significant bleeding, reduced blood flow to the bowel, or intussusception. Intussusception can block the bowel and cause severe, often wave-like abdominal pain, vomiting, or bloody stool.

Rare complications can affect the lungs, brain, or nervous system. New breathing difficulty, seizures, marked confusion, weakness, or loss of consciousness requires emergency help.

There is no reliable way to prevent IgA vasculitis. The immune reaction is not fully understood, and it often follows common infections that cannot always be avoided.

Routine hygiene can reduce the spread of respiratory and stomach infections, but it cannot guarantee that IgA vasculitis will not occur. There is no established diet, supplement, or screening test that prevents it.

A recurrence cannot always be prevented either. If symptoms return, renewed urine and blood pressure monitoring may be needed even if the first episode was mild.

The rash, joint pain, and abdominal symptoms usually improve over several weeks. New groups of spots may appear while older ones fade, so the rash can seem to come and go before it settles completely.

Joint symptoms generally improve without permanent damage. Abdominal symptoms also usually resolve, although severe or worsening pain needs reassessment rather than waiting for a routine appointment.

Some people have another episode after recovering. A recurrence may involve only the rash or may bring back joint, abdominal, or kidney symptoms. It is not always as severe as the first episode, but kidney checks remain important.

Most children return to their usual activities once pain, swelling, and energy levels allow. Time away from school may be needed during the acute illness, but isolation is not required because IgA vasculitis is not contagious.

The longer-term course is mainly determined by the kidneys. If repeated urine tests and blood pressure readings stay normal, lasting kidney problems become less likely. Persistent protein in the urine, high blood pressure, or reduced kidney function may require monitoring and treatment for years.

Adults can also recover fully, but kidney disease is more likely to be significant than it is in children. Keeping follow-up appointments is important even after the rash and pain have disappeared.

Arrange prompt medical assessment for a new non-blanching purple rash, especially when it occurs with joint pain, abdominal pain, or changes in urine. A clinician needs to distinguish IgA vasculitis from infections, blood disorders, and other causes of bleeding beneath the skin.

Seek same-day medical advice for:

• Increasing abdominal pain or repeated vomiting
• New blood in the urine or noticeably dark urine
• Swelling around the eyes, legs, or ankles
• Passing less urine than usual
• New scrotal pain or swelling
• A returning rash during follow-up

Seek emergency care for:

• Severe or constant abdominal pain
• Vomiting blood, black stool, or a large amount of blood in stool
• A non-blanching rash with fever and marked illness, unusual sleepiness, or neck stiffness
• Difficulty breathing, collapse, a seizure, confusion, or sudden weakness
• Severe dehydration or an inability to keep fluids down

Routine follow-up is still needed when you or your child feels well. Attend planned urine and blood pressure checks, and report new symptoms between appointments.

Is IgA vasculitis the same as HSP?

Yes. Henoch-Schönlein purpura, often shortened to HSP, is the older name. IgA vasculitis better describes the role of IgA and blood-vessel inflammation.

Is IgA vasculitis contagious?

No. The condition itself cannot spread between people. It may follow an infection, but that does not make the vasculitis contagious.

Does the purple rash go away?

It usually fades over several weeks, although fresh spots may appear during that time. Some spots can temporarily leave darker skin marks. A returning rash can occur and should be mentioned during follow-up.

Can IgA vasculitis come back?

Yes. Some people have one or more recurrences, often within the months after the first episode. A recurrence may be milder, but urine and blood pressure checks may need to restart.

Will it damage the kidneys?

Most children do not develop lasting kidney damage. However, kidney inflammation can occur without symptoms and may sometimes persist. Adults and people with substantial protein in the urine need especially careful follow-up.

Can I exercise or go back to school or work?

Usual activities can generally restart as pain, swelling, abdominal symptoms, and energy improve. IgA vasculitis does not require isolation. More time and medical guidance may be needed if the kidneys are affected or symptoms return with activity.