Vasculitis (Inflammation of blood vessels)

Overview

Vasculitis is a diverse set of illnesses defined by vascular inflammation. They have clinical, laboratory, and pathophysiologic aspects in common. The clinical and pathological aspects vary depending on the location and kind of blood vessels involved. Vasculitis can arise as a primary process or as a result of another underlying condition.

What is Vasculitis?

Vasculitis is an inflammation of the blood vessels, which are the tubes that transport blood throughout the body. Vasculitis can affect three different types of blood vessels:

• Arteries – take blood from the heart to different parts of the body such as organs (for example kidneys) and tissues (for example skin)
• Veins – take blood back to the heart
• Capillaries – tiny vessels between the arteries and the veins where oxygen and other materials pass from the blood into the tissues.

Vasculitis Causes

The etiology of different vasculitis is unknown; however, numerous risk factors that enhance the incidence and prevalence of vasculitis have been identified in the literature, including location, age, ethnicity, gender, genetic and environmental variables. Takayasu disease is more common in South Asian nations than in other parts of the world. Kawasaki disease affects young children under the age of five, whereas giant cell arteritis (GCA) affects the elderly. There is evidence that the prevalence of GCA has grown by a factor of 2 to 5 during the last 50 years.

Takayasu disease is more frequent in women (9 to 1) than in men, although Behcet disease is more severe in men, with a larger prevalence of advanced ocular disease. GCA and granulomatosis with polyangiitis (GPA) are more common in white people.

Which diseases are associated with Vasculitis?

The following are diseases that are associated with vasculitis:

• Polyarteritis nodosa

Polyarteritis nodosa is a rare multisystem illness characterized by extensive inflammation, thinning, and atrophy of small and medium-sized arteries. Blood vessels in any organ or organ system, including those feeding the kidneys, heart, gut, neurological system, and/or skeletal muscles, may be impacted. Destruction to affected arteries can cause unusually high blood pressure (hypertension), "ballooning" (aneurysm) of an artery wall, the production of blood clots (thrombosis), the restriction of blood flow to certain tissues, and/or tissue damage and loss (necrosis) in affected locations.

Weight loss, fever, a general sensation of bad health (malaise), weariness, weakness, headache, muscular pains (myalgias), and/or stomach discomfort are common symptoms. Although the actual etiology of polyarteritis nodosa is unknown, many experts believe the condition is caused by immune system malfunctions.

Hypersensitivity vasculitis refers to a variety of vasculitic disorders that affect the upper and lower respiratory tracts as well as the kidneys. They are typically the result of an allergic response to an unknown antigen.

• Wegener’s granulomatosis

Wegener's granulomatosis is a rare collagen vascular condition that often begins with a localized inflammation of the upper and lower respiratory tract mucosa and proceeds to a widespread inflammation of the blood vessels (vasculitis) and kidneys (glomerulonephritis). Other symptoms may include nasal ulcerations with subsequent bacterial infection, middle ear infection (otitis media) with hearing loss, cough, blood expectoration (hemoptysis), and inflammation of the thin membrane covering the exterior of the lungs and the interior of the chest cavity (pleuritis). It is unknown what causes Wegener's granulomatosis.

Lymphomatoid granulomatosis is a rare, progressive vascular disease characterized by lesions infiltrating and destroying veins and arteries. These lesions can affect several regions of the body, particularly the lungs. It can be either benign or cancerous.

• Buerger’s disease

Buerger's disease, also known as thromboangiitis obliterans, is a rare condition that primarily affects young to middle-aged male smokers. It is distinguished by the constriction or obstruction (occlusion) of the veins and arteries of the extremities, resulting in decreased blood flow to these regions (peripheral vascular disease). Legs are more commonly afflicted than arms. The first sign in most cases is severe discomfort in the lower arms and legs when resting.

Furthermore, affected people may develop sores (ulcers) on their extremities, numbness and tingling, as well as a lack of normal blood flow to their fingers and/or toes when exposed to cold temperatures (Raynaud's phenomenon), and/or inflammation and clotting of certain veins (thrombophlebitis). The specific etiology of Buerger's disease is unknown; nevertheless, the majority of those affected are smokers.

• Churg-Strauss syndrome

Churg-Strauss syndrome is an uncommon condition characterized by

• The development and accumulation of an unusually large number of specific white blood cells (eosinophils), 
• Inflammation of blood vessels (angiitis or vasculitis), and 
• Inflammatory nodular lesions in several organ systems (granulomatosis). 

Fever, a general sensation of weakness and exhaustion (malaise), loss of appetite (anorexia), and weight loss are also signs of Churg-Strauss syndrome. Asthma or allergies are frequently associated with it. The precise causes of Churg-Strauss syndrome are unknown. 

• Henoch-Schonlein purpura

Henoch-Schonlein purpura is a rare, self-limiting inflammatory illness of the tiny blood vessels (capillaries). It is the most prevalent kind of pediatric vascular inflammation (vasculitis) and causes inflammation in tiny blood vessels. Henoch-Schonlein purpura symptoms typically appear rapidly and include headache, fever, lack of appetite, cramping stomach discomfort, and joint pain. Typically, red or purple blotches form on the skin (petechial purpura).

This disorder can cause inflammation in the joints, kidneys, digestive system, and, in rare cases, the brain and spinal cord (central nervous system). Although the specific etiology of Henoch-Schonlein purpura is unknown, research indicates that it may be an autoimmune illness or, in rare cases, a severe allergic reaction to particular offending chemicals (e.g., foods or drugs).

• Behcet’s syndrome

Behcet's syndrome is a rare chronic relapsing inflammatory condition marked by ocular inflammation and mouth and genital ulcers. The reason is unknown. Areas of abnormal skin changes (ulcers or lesions) of the mouth and genitals that tend to recur spontaneously are symptoms. Other bodily systems, such as the joints, blood vessels, central nervous system, and/or digestive tract, may also be affected. 

• Kawasaki syndrome

Kawasaki syndrome, also known as mucocutaneous lymph node syndrome, is a juvenile inflammatory condition characterized by fever, skin rash, enlarged lymph nodes (lymphadenopathy), artery inflammation (polyarteritis), and blood vessel inflammation (vasculitis). Inflammatory alterations in blood arteries generate damaging lesions, which can lead to issues with the liver, gallbladder, and, most importantly, the heart.

The most common cause of acquired cardiac disease in children is Kawasaki syndrome. The specific etiology of Kawasaki syndrome is uncertain, however it may be linked to two previously undiscovered staphylococcus and streptococcus bacterium strains. 

• Urticarial vasculitis

Hypocomplementemic urticarial vasculitis is an uncommon illness marked by repeated bouts of vasculitis and urticaria accompanied by fever, arthritis, and stomach discomfort. Other symptoms include swelling (angioedema), ocular inflammation, and/or inflammation and degeneration of the capillary clusters (renal glomeruli) that filter the blood as it passes through the kidneys (glomerulonephritis). A chronic obstructive lung condition may occur in some circumstances. It is uncertain what causes hypocomplementemic urticarial vasculitis.

Primary angiitis of the central nervous system (CNS), also known as isolated vasculitis of the CNS, is rare disorder characterized by vasculitis of the CNS. The physical findings and symptoms of this condition are determined by the individual blood vessels of the central nervous system that are damaged.

There are other conditions that may be characterized by inflammation of certain blood arteries (vasculitis). Giant cell arteritis, polymyalgia rheumatica, lupus, essential mixed cryoglobulinemia, cutaneous necrotizing vasculitis, Cogan's syndrome type I, Takayasu's arteritis, and rheumatoid arthritis are among these disorders.

Vasculitis Symptoms

Vasculitis is a broad word for inflammation of blood vessels. This inflammation narrows the interior of the channel and can block blood flow to the tissues (ischemia). A shortage of blood can cause tissue destruction (necrosis), blood clot development (thrombosis), and, in rare circumstances, vessel wall weakness or ballooning, which can lead to rupture (aneurysm).

Arteries and veins of various sizes and locations throughout the body might be impacted. Vasculitis can be confined or isolated to a single organ or site, such as the skin, brain, or certain internal organs. In certain circumstances, vasculitis can affect many bodily locations or organs at the same time (systemic or generalized). It can arise on its own or as a result of a variety of other diseases.

Because vasculitis may impact so many different physiological systems, the symptoms are many. Muscle discomfort, joint pain, fever, weight loss, lack of appetite (anorexia), headache, or widespread weakness may occur depending on the system involved. Mouth ulcers, hoarseness, night sweats, high blood pressure (hypertension), stomach discomfort, diarrhea, blood in the urine (hematuria), or kidney (renal) failure may also occur.

Eye irritation and poor vision are additional symptoms, and blindness can develop in extreme cases. When the respiratory system is implicated, there may be sinus inflammation, runny nose, asthma, a cough with or without blood (hemoptysis), shortness of breath (dyspnea), nosebleeds (epistaxis), or lung membrane irritation.

When vasculitis affects the skin, there may be flat and red lesions (macules), nodules, and hemorrhages beneath the skin (purpura). These lesions can appear anywhere on the body, although they are more common on the back, hands, buttocks, inside of the forearms, and lower extremities. These skin problems might occur only occasionally or on a frequent basis. They often last a few weeks and may leave darker patches or scars. There may be wheel-like lesions that produce acute itching (urticaria) in some cases of vasculitis, as well as ring-shaped lesions and ulcers. In extreme instances, blister-like lesions (vesicles, bullae) may form.

Vasculitis Diagnosis

When suspecting vasculitis workup should include:

• A complete blood cell count (CBC) (usually associated with neutrophilia, anemia, and thrombocytosis),
• Kidney function (may be abnormal in renal involvement from GPA, Churg-Strauss etc), 
• Liver function studies, 
• Erythrocyte sedimentation rate (ESR) 
• C-reactive protein (CRP), [elevation in acute phase reactants noticed in most vasculitis], 
• Serologies for viral hepatitis (hepatitis B in PAN), 
• Serum cryoglobulins, and 
• A urinalysis with urinary sediment. 

Anti-neutrophil cytoplasmic antibodies (ANCA), anti-nuclear antibodies (ANA), complement levels (low complement levels associated with mixed cryoglobulinemia), immunoelectrophoresis (monoclonal gammopathies can occur in Hepatitis C related vasculitis), and a work-up to rule out vasculitis mimics such as infections should be performed.

• Imaging

In patients with respiratory symptoms, a radiographic examination, such as a chest x-ray or high-resolution computed tomography (HR-CT), is recommended. Many vasculitides require a biopsy of the affected tissue to be diagnosed. In situations of suspected GCA, a temporal artery biopsy should always be included in the workup. Skin biopsies of purpuric lesions and renal biopsies in glomerulonephritis patients offer good diagnostic yields.

For individuals with suspected GPA, CT sinus imaging may be required. To detect big artery lesions, vascular imaging techniques such as magnetic resonance imaging (MRI), MR angiograms, CT angiograms, vascular ultrasonography, and positron emission tomography (PET) may be employed.

Vasculitis Treatment

The kind of vasculitis determines the treatment. If an offending antigen is identified, such as hepatitis infection, it should be treated accordingly alongside the vasculitis treatment plan. Treatment plans are based on the exact diagnosis as well as the degree or breadth of the condition. Treatment for any vasculitis typically consists of three components: remission induction, remission maintenance, and monitoring.

Glucocorticoids, with or without immunosuppressive drugs, are the first-line therapy for patients with vasculitis. The kind of vasculitis influences the immunosuppressive drugs used. Methotrexate (MTX), azathioprine (AZA), mycophenolate (MMF), cyclophosphamide (CYC), rituximab (RTX), intravenous immunoglobulin, plasma exchange, and other medications have all been utilized in various vasculitis therapy regimens.

Once the illness is in remission, moderate, downward glucocorticoid titration should begin to maintain disease control while minimizing the risk of medication toxicity. For monitoring purposes, patients and clinicians should be aware of the short-term and long-term harmful side effects of therapeutic drugs.

Steroids, commencing at dosages of 40 to 60 mg per day, in single or split doses, are used to treat Giant cell arteritis (GCA). In individuals with a high suspicion of GCA, glucocorticoid therapy should begin immediately. In individuals who have recently lost eyesight, intravenous pulse steroids are an alternative. Steroids should be gradually tapered off after remission. Methotrexate and azathioprine can be used as steroid substitutes. Tocilizumab was recently licensed for the treatment of GCA.

Differential Diagnosis

Vasculitis has various mimics; thus, thorough differential examination is required when evaluating such individuals. Infections such as infective endocarditis, histoplasmosis, and gonococcal infection can all resemble vasculitis. Because the treatment of vasculitis necessitates the use of immunosuppressive medicines, all patients with suspected vasculitis should have a complete infection test. Coagulopathies such as antiphospholipid syndrome and thrombotic thrombocytopenic purpura, neoplasms such as atrial myoma and lymphoma, and medication toxicity such as cocaine and levamisole can all cause symptoms similar to vasculitis.

Prognosis

The long-term survival of vasculitis patients is strongly dependent on the diagnosis, response to therapy, adverse medication effects, and the presence of infections. In one research, the 1-, 2-, and 5-year survival rates in ANCA-associated vasculitis were 88 percent, 85 %, and 78 percent, respectively. In comparison to the overall population, the mortality ratio was 2.6. Deaths are reported as a result of both active vasculitic illness and therapeutic effects.

Complications

The type of vascular implicated determines the sort of vasculitis complications. Large vascular involvement with vasculitides such as GCA, Takayasu, or Kawasaki can result in consequences such as acute myocardial infarction, stroke, mesenteric ischemia, aortic syndromes (including dissection or intramural hematoma), or critical extremities ischemia.

Alveolar hemorrhage, renal failure, and intestinal ischemia are all life-threatening complications of small-vessel vasculitis. GCA, polyarteritis nodosa, and Behcet illness are all known to cause aneurysm development. AAV and Behcet disease have a higher rate of deep venous thrombosis and pulmonary embolism than other vasculitides.

Conclusion 

Vasculitis is an autoimmune-related blood vessel inflammation. It occurs when the body's immune system mistakenly targets a blood vessel. It can occur as a result of an infection, a medication, or another condition. The reason is frequently unknown. Vasculitis can cause damage to the arteries, veins, and capillaries. Arteries are blood arteries that transport blood from the heart to the organs of the body. Veins are the blood veins that return blood to the heart.

Capillaries are small blood vessels that join the arteries and veins. When a blood artery gets inflamed, it might narrow, making it more difficult for blood to pass through, close entirely, preventing blood from passing through, or expand and weaken to the point where it bulges. An aneurysm is a kind of protrusion. If it bursts, it might cause serious internal bleeding. Symptoms of vasculitis vary, but typically include fever, edema, and an overall feeling of being sick. The primary objective of therapy is to reduce inflammation. Steroids and other anti-inflammatory medications are frequently beneficial.