What is Henoch-Schonlein Purpura?

Henoch-Schonlein purpura is a vascular disease of the circulatory system. The primary symptoms are gastrointestinal, and also affect the skin and joints. Henoch-Schonlein purpura is more common in children, though it does occur in adults. While not chronic and rarely leading to long-term complications, in adults, the symptoms of the disease are typically more severe and last longer. The condition generally resolves on its own without treatment, and over-the-counter or prescription medication can alleviate symptoms.

Henoch-Schonlein Purpura History

The presentation of Henoch-Schonlein purpura was first described at the turn of the nineteenth century by William Heberden, a physician in London. Heberden reported on the condition of a child in his care with symptoms now understood to characterize the disease. Later in the 1800s, the namesakes of the condition, Johann Schonlein and Edouard Henoch, reported further findings on the disease. These findings included the potential cause of Henoch-Schonlein purpura as well as variations in prognoses.

Pathology of the Disease

Henoch-Schonlein purpura or HSP is defined by inflammation and leaking of the blood vessels in the intestines, joints, kidneys, and skin. It is a form of vasculitis, a broad diagnosis referring to any condition that affects the vascular system — the body’s blood vessels. White blood cells produce antibodies, which should protect the body from illness. In people with Henoch-Schonlein purpura, however, an abnormal immune response occurs, and the antibody immunoglobulin A is atypically deposited in the walls of the blood vessels. Essentially, the antibody attacks the vascular system.

Causes of Henoch-Schonlien Purpura

The cause of Henoch-Schonlein purpura is not clear. HSP most often occurs following a bacterial or viral infection such as an upper respiratory infection, chicken pox, or strep throat. Cold weather, insect bites, food allergies, and medication have also been found to trigger the antibody’s attack on the blood vessels. In spite of knowledge of these predisposing factors, experts still do not entirely understand why the immune system responds abnormally in people with HSP.

Risk Factors and Prevalence

Henoch-Schonlein purpura is primarily a disease of childhood, with 90% of all occurrences affecting individuals ten and under. The condition most commonly develops between the ages of two and six. Around 140 cases per one million people are diagnosed each year. HSP is diagnosed more frequently in boys than girls and occurs more commonly in people of Caucasian and Asian descent. Research has indicated the possibility of a genetic predisposition, as well.

Symptoms

HSP presents primarily as gastrointestinal disturbances, joint pain, and purpura or skin hemorrhages. Symptoms include stomach pain, nausea, vomiting, and painful and swollen joints. The telltale symptom of the disease is the purpura, the rash on the skin caused by leaking blood vessels. Also called blood spots, this sign can appear as small red dots or larger, darker splotches resembling bruises. If the kidneys are affected, individuals may experience blood in their urine.

Complications of Henoch-Schonlien Purpura

Long-term complications are rare but do occur, primarily in adults. The most common complication of Henoch-Schonlein purpura is kidney damage. HSP leads to renal failure in around 1% of children and up to 40% of adults. Another complication is intussusception, which causes the intestines fold upon themselves and obstruct the bowels. Pustular and vesiculobullous lesions may form on the areas affected by the purpura. Development of lesions is rare and particularly uncommon in children.

Diagnosing Henoch-Schonlien Purpura

A doctor can often diagnose Henoch-Schonlein purpura on the basis of a physical exam and a thorough history of the symptoms. If additional diagnostic testing is necessary, the patient may require a skin biopsy or urinalysis. The tissue collected in a skin biopsy reveals antibody deposits on the skin. A urinalysis can detect hematuria or proteinuria – blood or excess protein, respectively – in the urine. If the doctor suspects the kidneys are affected, he or she may call for a kidney biopsy.

Treatment

There is no one medication or therapy for Henoch-Schonlein purpura, and the disease typically resolves within several weeks. Doctors recommend rest, fluids, and over-the-counter pain and anti-inflammatory medication. Depending on the severity of the symptoms, stronger medication may be prescribed. Corticosteroids can treat joint and abdominal pain, though the drug’s benefits must be weighed against its potentially harmful side effects.

Medical Intervention

In rare cases, patients may require more invasive medical intervention to treat their symptoms and complications. Severe pain, gastrointestinal bleeding, and kidney damage can call for hospitalization. If intussusception in the bowels occurs, surgery can correct the folded intestines. Significant damage to the kidneys may require immunosuppressive medication, dialysis, or a kidney transplant.

Prognosis

Henoch-Schonlein purpura is not chronic, and serious complications are rare. There is risk of the purpura recurring when the individual resumes normal activity following the initial episode, but the rash is typically minor and other symptoms absent. Most children and adults diagnosed with HSP recover within several weeks with no long-term damage to their health. Those who experience complications of the gastrointestinal system or kidneys often receive a positive prognosis, assuming proper management of their condition. HSP is rarely fatal; death from renal failure occurs in just 1% of diagnoses.