|What is Henoch-Schönlein purpura (HSP)? |
What causes HSP?
What are the Symptoms?
What is the Treatment?
What can I do?
What is the long term outlook?
HSP is a condition where there is inflammation of blood vessels. It is one of a family of conditions called vasculitis. The names of some the various types of vasculitis are: microscopic polyarteritis, Wegener’s granulomatosis, Henoch-Schönlein purpura and polyarteritis nodosa (Click here for more details on vasculitis).
The cause is immunological. That is, the white blood cells and antibodies (natural defences) that are present to fight off infection are damaging the body by mistake. The body’s defences against infection are very powerful and many diseases are due to their overactivity such as asthma, rheumatoid arthritis and diabetes in young people.
In HSP blood vessels in particular are damaged. Doctors do not understand fully why this happens and the condition is quite rare. HSP with kidney involvement affects 5 - 10 people per million population per year.
The trigger that starts HSP varies from person to person. Sometimes it is a ‘flu-like infection’, sometimes it appears to be an operation or a bacterial infection. The condition is commoner in the spring and autumn than in the summer and is commoner in younger people, unlike other types of vasculitis which are commoner in older people.
These are variable and almost every case is different from each other. Often the only symptom is a feeling of tiredness and general ill health. Blood vessels in all parts of the body can be affected; here are some of the commoner symptoms:-
- Skin: small blood vessels in the skin can become damaged by HSP, causing them to burst, causing a rash with small red blotches. This is most commonly seen on the lower legs and the buttocks.
- Kidneys: the specialised small blood vessels in the kidney which filter blood to make urine seem especially sensitive. The damage to the kidney can cause blood to appear in the urine as well as kidney failure in severe cases.
- Joints: inflammation around the joints can cause pain and stiffness.
- Other parts of the Body: abdominal (tummy) pain is quite common in HSP, and although almost every part of the body may be affected in some cases of HSP, the majority of cases are restricted to the skin, kidneys, joints and tummy.
In some cases, especially if there is no involvement of the kidneys, the condition may go away on its own without the use of drugs other than simple painkillers if the joints are inflamed. Steroid (prednisolone) treatment is required in some cases (Click here for more details on steroid treatment).
The easiest way to see if there is kidney involvement in HSP is to test the urine for blood with a dipstick. If this is negative, the kidneys are unlikely to be involved. If it is positive, blood tests to measure the function of the kidneys will give an indication as to the severity of involvement. If there is a suspicion of severe kidney involvement, a kidney biopsy may be advised.
If there is kidney involvement, treatment may be advised with a combination of steroids (prednisolone) and cyclophosphamide. These are both powerful drugs that reduce the activity of the immune system, reducing the activity of HSP. High doses of these drugs are normally given for the first 3-6 months after which doses are reduced to maintenance levels. Some treatment is needed for at least 2 years.
These drugs can cause serious side effects and very careful monitoring is required for the sake of safety. The main side effect is infection. There is a risk of severe urine infection or pneumonia during the first few months of treatment and any fevers or possible infection should be reported urgently to your doctor.
Unfortunately it seems there is nothing you can do in your lifestyle or diet that will stop you getting HSP. Similarly, there is little you can do that would prevent you getting a relapse. However, what you do still makes an enormous difference to your health:-
- Remember to take your medication at the times prescribed. Doctors often change the doses of tablets, so make sure you know exactly what has been advised. If in doubt about the dosage of tablets, ’phone up your Doctor and check.
- Report possible complications of treatment such as symptoms of infection at an early stage.
- Take regular exercise. People with HSP lose a lot of muscle strength during illness. Ask for advice about sensible regular exercise.
- Eat well. You will probably lose some body weight with HSP in its early stages. Even if you have a weight problem, this weight loss is usually a bad thing, because it is your muscle and not your fat that is lost. Please take advice from the renal dietitians about regulating your diet properly.
Most people with HSP recover completely, and do not get problems with their health in the future. A few people get recurrent attacks of rash and joint pain, sometimes with kidney involvement. These may merit treatment with steroids, but may settle down over a period of a couple of years.
Occasionally there seems to be more severe damage of the kidneys, either with large amounts of protein in the urine, or reduced level of kidney function on blood tests. If this happens, the blood pressure should be treated intensively (Click here for information on controlling blood pressure), and further consideration will be given to the possible value of steroids in protecting the kidneys against severe long term damage. However, this circumstance is rare, and many people have perfectly normal long term kidney function, even if they have low levels of protein in the urine.
The National Kidney Federation cannot accept responsibility for information provided. The above is for guidance only. Patients are advised to seek further information from their own doctor.