Exploring Childhood Vasculitis: Types, Risk Factors, and Prognosis

Introduction

Vasculitis includes a broad category of diseases, all involving inflammation of blood vessels. It is rare in children (below the age of seventeen). When the blood vessels are involved, it affects the blood flow, giving rise to multiple problems; some may even be of serious concern.

What Is Childhood Vasculitis?

Vasculitis, inflammation of the blood vessels, happens when the body's immune system attacks one or more blood vessels. This self-attack on blood vessels causes inflammation which narrows or blocks the blood vessel completely. In some rare cases, the blood vessels can stretch up to form an aneurysm (bulge in the blood vessel) or become weak and rupture. Rupturing of blood vessels can cause internal bleeding and be serious if it involves organs like the heart and lungs.

Vasculitis can affect the veins (carry blood from organs to the heart), arteries (carry blood from the heart to organs), or capillaries (which connect small arteries and veins).

What Causes Childhood Vasculitis?

The exact cause of vasculitis is not known. However, researchers believe genetic and environmental factors could cause it. Depending on the possible cause, vasculitis can be:

• Primary Vasculitis - when vasculitis is specific to an organ or a systemic disease.

• Secondary Vasculitis - when vasculitis is caused as a symptom of an underlying disease (HIV), medications (minocycline), cancer (lymphoma), or any other autoimmune conditions (rheumatoid arthritis)

What Are the Types of Childhood Vasculitis?

Childhood vasculitis is classified based on the size of the affected blood vessel and the presence or absence of granuloma.

• Predominantly Large Vessel Vasculitis - the aorta and its major branches: Takayasu arteritis

• Predominantly Medium Vessel Vasculitis - arteries supplying organs like the brain, heart, and kidney.

  1. Childhood polyarteritis nodosa.

  2. Cutaneous polyarteritis.

  3. Kawasaki disease.

• Predominantly Small Vessel Vasculitis - small capillaries

  1. Granulomatous - Wegener's granulomatosis, churg-strauss syndrome

  2. Non-Granulomatous - Henoch- schönlein purpura, microscopic polyangiitis, isolated cutaneous leukocytoclastic vasculitis, hypocomplementemia urticarial vasculitis.

• Other

  1. Behcet disease.

  2. Vasculitis is associated with infection, medications, or malignancies.

  3. Vasculitis is associated with connective tissue disease.

  4. Isolated vasculitis of the central nervous system.

  5. Unknown causes.

Henoch-schönlein purpura and Kawasaki disease are the common types found in children, and the other types of vasculitis rarely occur in children.

What Are the Symptoms of Childhood Vasculitis?

Symptoms vary from mild to severe depending on the size of the affected vessels, site of vessel involvement (organ or skin), vascular injury (aneurysm or rupture), and whether the underlying cause is localized or involves multiple blood vessels. Symptoms can be:

• Unexplained pain in muscles and joints.

• Headache.

• The unexplained onset of fever.

• Night sweats.

• Tiredness.

• Loss of appetite.

• Weight loss.

Symptoms may also present depending on involvement with a particular organ of the body.

• Skin - bleeding under the skin shows as red spots or purplish rash. Open sores and lumps in rare cases.

• Hands and feet - pain, swelling of the soles, and may cause numbness or weakness.

• Eyes - blurred vision, red dry, itchy eyes.

• Ear - affects the body's balance causing dizziness.

• Lungs - shortness of breath on mild exertion, site of blood when coughing.

• Abdomen - abdominal pain, cramps, diarrhea, ulcers, blood in the stool.

• Kidney - brown or dark-colored urine, may also see blood in the urine.

• Multiple blood vessel involvement shows symptoms involving organs simultaneously.

In some rare cases, severe complications may arise depending on the type of vasculitis. For example, kidney inflammation (nephritis) is commonly seen for Henoch-schönlein purpura as it attacks the blood vessels around the kidney, and since Kawasaki involves blood vessels around the heart, it may interfere with heart rate or even cause heart attacks.

How to Diagnose Childhood Vasculitis?

Symptoms being similar to many other diseases or conditions makes diagnosing vasculitis difficult. Therefore, an early and efficient diagnosis is required before the disease progresses to serious complications. On suspicion of vasculitis in a child, the pediatrician (doctor for children) may refer the child to a rheumatologist (doctor of connective tissue, muscle, and joints) who can confirm the diagnosis. Diagnosis is confirmed by:

• Blood Test - Complete blood count (CBC), erythrocyte sedimentation rate (ESR), C- reactive protein, anti-neutrophil cytoplasmic antibodies (ANCA).

• Urine Test - To check if a kidney is affected; blood and protein in the urine.

• Chest X-ray - To check if lungs are affected.

• Ultrasound - To check if the abdomen is affected.

• Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) - It is used to check if the brain is affected.

• Angiogram - It is used to show how the blood vessel is affected with the help of a dye injected into the arteries and veins.

• Biopsy - To check the inflamed blood vessel or suspected organ.

How to Treat Childhood Vasculitis?

Once the diagnosis is confirmed, the treatment must not be delayed as vasculitis can progress to a serious condition easily since it involves blood vessels. The treatment depends on the vessels involved, organ involvement, and severity of vasculitis. The treatment modalities aim to slow the progression or stop it altogether.

• Nonsteroidal Anti-inflammatory Drugs (NSAIDs) - Ibuprofen to ease the aches and pain of muscles and joints.

• Corticosteroids (Prednisolone) - A fast-acting, potent drug that fights inflammation of the blood vessels by suppressing the immune system. Prolonged use of corticosteroids has adverse side effects on health, so it must be used cautiously and for a short period under monitoring.

• Steroid-sparing Immunosuppressive or Disease-Modifying Anti-Rheumatic Drugs (DMARDs) - Cyclophosphamide, Azathioprine, Methotrexate, Mycophenolate Mofetil, or MMF (CellCept). Action is similar to corticosteroids and has a lesser side effect. However, they are slow in onset.

• Biologics - Infliximab, Rituximab, or Tocilizumab- new series of steroid-sparing immunosuppressants made from living cells that target specific immune system functions, thereby causing lesser side effects than other lines of drugs.

• Intravenous Immunoglobulin-G (IVIG) - Intravenous administration of immunoglobulin-G antibodies that are prepared from a healthy donor's plasma and have minimal side effects, can fight infections without suppressing the immune system.

• Surgery - Indicated to clear aneurysms or blocked vessels to restore blood flow. It is also indicated for serious cases where organs are involved, and life is at risk.

Some children tend to recover from vasculitis without any treatment. This is a possibility; however, a doctor's diagnosis of vasculitis is advised to prevent complications due to the progression of vasculitis. Some children may also need lifelong therapy to prevent the relapse of vasculitis and to prevent damage to any vital organ.

Conclusion

Prompt diagnosis and treatment and a positive body response towards the treatment can help one recover from vasculitis within six to twelve months. Then the medications may slowly be weaned off by the doctor depending on the individual's condition and assessing the possibility of vasculitis relapse. Treatment aims to achieve remission so young children can have a productive life.