Polyarteritis Nodosa

Polyarteritis Nodosa (PAN) is a rare and serious autoimmune disease. I t involv es immune cells attacking the arteries, the blood vessels that transport pure blood to the organs. The consequence is swelling of the arteries, leading to damage or blockage. Thus, organs get deprived of blood and hence oxygen.

The disease was first found in 1866 by Kussmaul and Maier. They discovered inflamed nodules in medium-sized arteries during a patient’s autopsy.

What is Vasculitis?

Vasculitis means inflammation of the blood vessels in the body. The inflammation can weaken the vessel walls and cause many problems. Blood vessels may become narrow or even close completely.

They may stretch and form bulges called aneurysms. In some cases, vessels can burst and bleed into tissues. PAN is a type of vasculitis. It affects only medium-sized arteries and not the small or large ones.

Symptoms of Polyarteritis Nodosa

Symptoms of PAN vary between individuals, as the disease can affect multiple organs and systems in the body. Common symptoms of PAN include:

Fever, fatigue, and general feeling of being unwell
Sudden weight loss and loss of appetite
Muscle aches and joint pain
Abdominal pain or cramping
Skin problems: red or purple spots, bumps, or ulcers
Nerve issues: pain, numbness, or tingling in hands and feet
High blood pressure (especially if kidneys are involved)
Heart or kidney complications in severe cases
Nervous system problems: seizures, memory issues, confusion

Causes of Polyarteritis Nodosa

PAN is not cancerous, inheritable, or contagious. It is a disease of the immune system and blood vessels. The exact cause of PAN is still unknown, but it is primarily an autoimmune disorder marked by the immune system attack ing the body’s own blood vessels.

Sometimes PAN is linked to infections like hepatitis B, though vaccination has reduced such cases. Some people may develop PAN after certain drug use or allergic reactions. The disease has also been seen in people who use amphetamines or other harmful drugs.

Diagnosis of Polyarteritis Nodosa

Diagnosing PAN is challenging because it looks like other diseases. Doctors start with symptom review and physical examination. Tests are done to determine affected organs.

Blood tests can reveal signs of inflammation or anaemia.
Urine tests check for kidney damage.
Imaging, like X-rays, CT, or MRI scans identifies affected areas.
Confirmation test also requires an arteriogram (injects dye to visualise vessels on X-ray) or biopsy (studying tissue samples to find inflammation in the arteries).

Treatment of Polyarteritis Nodosa

PAN treatment works by lowering inflammation and preventing organ injury. It often continues for months or longer. Most patients can manage symptoms well with the following treatment:

Regular cases: Corticosteroids such as prednisone or prednisolone are common medications. They help calm the immune response against blood vessels.
Severe cases: D octors add immunosuppressants like cyclophosphamide. This medicine helps control the disease when steroids alone aren’t enough. Antiviral drugs may be needed if hepatitis B is involved.

Summary

PAN is a rare condition that involves inflammation of medium-sized blood vessels. It harms multiple organs lik e the kidneys, heart, nerves, and skin. Typical symptoms include tiredness, fever, weight loss, and pain. PAN is connected to immune system problems and sometimes hepatitis B infection.

Doctors diagnose PAN with blood and urine tests and a few scans. Treatment includes the use of corticosteroids, immunosuppressants, and antiviral drugs, depending on the severity of the case.

FAQs

Q1. How is hepatitis B infection linked to the pathogenesis of PAN?

Hepatitis B virus infection leads to the deposition of immune complexes in the walls of the medium-sized arteries. It leads to inflammation and vascular injury, thus contributing to PAN development.

Q2. What is ANCA testing in PAN?

Anti-Neutrophil Cytoplasmic Antibodies (ANCA) testing involves detecting autoantibodies against neutrophil proteins. The ANCA testing is generally negative in PAN, allowing distinguishing it from ANCA-associated small vessel vasculitis.

Q3. Why are corticosteroids used in PAN?

Corticosteroids reduce immune-mediated inflammation, making them effective against PAN.