Vasculitis, simply put, is blood vessel inflammation. But vasculitis is far from a simple subject. It is not one, but a multitude of diseases with a wide variety of manifestations, ranging from skin involvement alone to widespread life-threatening damage to multiple organs.
The size of the inflamed blood vessels largely determines the type of vasculitis that is experienced. Blood vessels that are undergoing inflammation may occlude, narrow, or in the event of bigger vessels, expand. The complications found in various kinds of vasculitis are caused by this process. These illnesses can generally be categorised into small, medium, & large vessel vasculitis, however there is often overlap in specific patients.
Vasculitis is a broad term that covers a variety of distinct diseases, although frequently blood vessel irritation is recognised without being able to diagnose a particular condition. Cryoglobulinemic vasculitis, Henoch-Schönlein purpura, leukocytoclastic cutaneous vasculitis, & microscopic polyangiitis are all examples of small vessel vasculitis (MPA).
Polyarteritis nodosum (PAN), Wegener's granulomatosis (WG), Churg-Strauss syndrome (CSS), and primary angiitis of something like the central nervous system are among the conditions regarded as types of medium vessel vasculitis (PACNS). Last but not least, Takayasu's arteritis and giant cell arteritis (GCA) are disorders that mostly manifest as big vessel vasculitis (TA). Giant cell arthritis (GCA) is covered in-depth elsewhere (see the section on Polymyalgia Rheumatica/GCA).
The aforementioned ailments are thought to be main types of vasculitis, but many other illnesses are connected to what is thought to be secondary vasculitis. Different types of vasculitis have been linked to a variety of illnesses, including infections (HIV, hepatitis B or C, microbial, fungal), cancers (leukaemia, lymphoma, solid tumours), drugs (PTU, hydralazine, antibiotics), and other rheumatic conditions (rheumatoid arthritis, systemic lupus Sjögren's syndrome). When vasculitis is identified, therefore, it is prudent to search for potential secondary causes, which can greatly influence how the patient is treated.
The capillaries, which are small blood vessels that are frequently invisible to the unaided eye and carry blood to different parts of the body, come to mind when we talk about small blood vessels. Small blood arteries feeding the nerves, kidneys, lungs, or intestines could become inflamed and may cause harm in these tissues, however the skin is most frequently involved in a patient with small vessel vasculitis. The main characteristics of various kinds of microvascular vasculitis are presented in Table 1.
Purpura, which appears as elevated red or purple spots and can range in size from a pinpoint to an inch in diameter, is the common finding when the skin is implicated. Skin ulcers, painful red nodules, and a lacy red or purple rash known as livedo are other findings that can suggest a diagnosis of vasculitis.
Other organs that have blood vessel inflammation may experience more severe problems. Mononeuritis multiplex, a nerve condition, can result in numbness or paralysis in an arm or leg. Patients with this condition frequently experience "wrist drop" or "ankle drop," respectively, which refers to difficulty moving a hand or foot. Examples of diseases that can present in this fashion include MPA and cryoglobulinemic vasculitis. Renal involvement can decrease kidney function and cause blood or protein to appear in the urine. Pain near the kidneys is nearly never present with this. Kidney dysfunction frequently complicates HSP and MPA. In MPA patients, small blood vessels inside the lung may also become inflamed, resulting in lung damage that may appear to be influenza on chest x-rays.
Medium-sized vessels are too little to be assigned a name, yet they are large enough to be referred to as arteries or veins. Inflammation of these blood vessels frequently results in the organ in question losing its blood supply, which has the possibility of causing extremely serious harm. PAN typically only exhibits inflammation of the size of vessel, in contrast to many illnesses that are primarily thought to be medium vessel vasculitis (WG, CSS, and PACNS, for example). Table 2 provides a summary of the salient characteristics of different vasculitis types. Numerous variations of medium vessel vasculitis attack the kidneys. PAN causes increased blood pressure because sections of the kidney may lack blood flow. When the kidneys are affected by WG or CSS, blood or protein may appear in the urine, which can occasionally lead to renal failure. Lung disease is typically absent in PAN, but it is frequently present in WG, often accompanied with cavities or nodules inside the lung tissue, and is almost always present in patients with CSS, which is linked to asthma. The sinuses, eyes, or trachea (or "windpipe") may become inflamed or injured in WG, and less frequently in CSS.
Although less frequent in WG, individuals with PAN or CSS may experience cardiac and digestive system involvement, which can lead to life-threatening complications & damage. PACNS, a rare disorder that causes strokes, headaches, confusion, and fever, only affects the brain.
However, other types of vasculitis, such as PAN and CSS, can also affect the brain and harm important nerves, as is the case with small vessel vasculitis.
We shall concentrate on TA, another significant form of big vessel vasculitis, as GCA is covered elsewhere (see Polymyalgia Rheumatica/Giant Cell Arteritis section). Despite the fact that both these conditions affect the same blood arteries, they affect people of different ages; TA primarily affects young Asian women, while GCA primarily affects elderly Caucasian adults. A "big" vessel affected by vasculitis is typically one that is significant enough to have a name. The main blood vessel inside the body, the aorta, and its branches are frequently impacted.
The most common finding when large vessels become inflamed is pain in the region that blood vessel supplies. While headaches and jaw pain are the most common features of GCA, patients with TA most commonly will have pain in an arm due to narrowing of its large blood vessels. Claudication is a symptom that is increased when the patient uses their arm. Dizziness, fainting spells, and strokes are less frequent symptoms of constricted blood arteries leading to the brain. The aorta typically dilates when it is inflamed, which cause heart murmurs & strain just on heart can muscle.
In order to confidently diagnose vasculitis, it is ideal to have evidence of the affected blood vessels' inflammation. It may be difficult to perform the procedures necessary to diagnose vasculitis in this fashion, but the investment in these kind of efforts is sensible given the risks associated with misdiagnosed and uncontrolled vasculitis as well as the risks associated with therapy.
Reviewing the patient's symptoms and the results of the physical examination is the first step in any successful evaluation. An expert practitioner may suspect vasculitis if several of the issues mentioned above are present. Generally speaking, vasculitis must be taken into account if unexplained fever and injury to any organ occur, especially when it cannot be predicted (a stroke inside a young child, for example).
Laboratory tests typically demonstrate elevations in markers of inflammation, such as the sedimentation rate and C-reactive protein. These tests, however, are also elevated in patients with a number of other inflammatory diseases and infections are not specific enough to make a diagnosis. Blood counts can reveal elevations in specific types of white blood cells implicated in inflammation, and blood chemistry studies can indicate consequences of vasculitis, such as reduced kidney function (particularly useful in patients with suspected CSS). The easiest way to identify kidney involvement early is to collect a urine sample and test it for blood and/or protein.
Studies on immune system anomalies and antibodies tests may shed more light on the patient's issues.
The rheumatoid factor and antinuclear antibody are markers for RA and SLE or Sjögren’s syndrome but may be elevated in certain forms of vasculitis or may indicate that the vasculitis is secondary to one of these illnesses. In some types of vasculitis, the blood levels of complement, a protein that can help with diagnosis, are low whenever the immune system is active. Several kinds of vasculitis can be detected in patients by measuring cryoglobulins, proteins that thickens the blood in colder temperatures. Antineutrophil cytoplasmic antibody may be the most practical antibody marker (ANCA).
This antibody, which was only recently found, is a significantly more accurate marker for several different types of vasculitis, particularly WG. Positive ANCA test results are also frequently seen in other disorders like CSS and MPA. Additionally, in some patients, the ANCA might be used as a marker for disease severity.
In order to rule out any potential secondary causes of vasculitis, additional laboratory tests may be necessary. Tests for exposure to hepatitis, HIV, and other infections are worthwhile in addition to some of the antibody tests indicated above, especially in those who are at risk for these conditions. The fact that hepatitis C infection is typically linked to cryoglobulinemic vasculitis is notable and has a significant effect on treatment.
Despite all the tools mentioned above that can be used to identify vasculitis, a biopsy of the region where the disease is still most active or in the region where this type of procedure can be done most easily is the "gold standard" for a certain diagnosis. If there are abnormalities, this is easiest to do on the skin, but it can be done on other organs reasonably safely as well. The risk of taking a biopsy from these regions is typically warranted in cases where the kidney, intestines, lungs, or even other organs are in danger. This is the most straightforward method of clearly capturing blood vessel irritation, which can be seen under the microscope in real time.
An arteriogram, or angiography, is a viable alternative in cases where larger blood arteries are thought to be implicated or where a biopsy would be risky. The target blood vessels are dyed during this operation, and the alterations are then seen under an x-ray viewer.
Although smooth channel narrowing, dilation, or a "beaded" appearance are all signs of vasculitis, it is still important to separate these symptoms from cholesterol plaques in the veins, especially in elderly individuals. A magnetic resonance (MRI) or magnetic resonance angiography (MRA) may show changes indicative of vasculitis, especially in the brain. However, despite being less strenuous on the patient, these tests are less precise than the usual arteriogram in identifying blood vessel abnormaliti
The myriad disorders that fall under the umbrella term of vasculitis are as diverse as the appropriate treatment for vasculitis. The rarity of many of these ailments makes it challenging to locate thorough research with sound design. In order to treat many of these conditions, the practitioner is left to rely on a combination of the finest knowledge available, his or her own experience, and judgement.
Treatment for vasculitis that affects only the skin, like LCV, is determined by the disease's severity and symptoms. In some people, the vasculitis may go away on its own, improve once a medication is stopped, or respond to other potential triggers. The majority of individuals need some kind of treatment, which may include antihistamines, colchicine (marketed as Plaquenil), which is also prescribed to treat gout as well as other inflammatory diseases, dapsone (used to treat leprosy and other skin conditions), or hydroxychloroquine (used to treat RA or SLE). Corticosteroids are only necessary in severe situations. These drugs temporarily reduce inflammation, but long-term usage is linked to weight gain, bone thinning, cataracts, blood sugar rise, and other negative effects (see Medications section).
The situation alters when vasculitis complications impact other organs. Aggressive treatment is required for these patients. High-dose corticosteroids should be used as the first line of treatment for the majority of patients with these forms of vasculitis. Steroids may be the only treatment required in individuals with PAN, MPA, CSS, PACNS, TA, or GCA. If a satisfactory response is shown, the dose can be decreased and subsequently stopped. Immunosuppressive medications including cyclophosphamide (CYC), azathioprine (AZA), methotrexate (MTX), or a more recent therapy called mycophenolate mofetil (MMF, brand name Cellcept) have been used successfully in individuals with persistent damage or more severe disease. Numerous of these treatments have potential adverse effects that need to be carefully watched for, including infection, a decrease in blood counts, including liver damage.
The scenario is unique for WG patients. A combination of steroids and oral CYC can now put this illness, which was historically nearly always deadly, into remission in up to 90% of patients. Many authorities advise switching to maintenance therapy with the other medications (MTX, AZA, or MMF) once the condition is under control because side effects are an issue with the long-term use of CYC.
Certain types of vasculitis are being studied in relation to more recent drugs that have been employed in treating other rheumatic disorders. These medications, also referred to as biologic offer guidance, must be injected or injected into a vein. Examples include tumour necrosis factor inhibitors, rituximab, a medication that blocks the activities of certain white blood cells, and interferon, a medication that also has action against viruses like hepatitis. All of these drugs should only be used in cases when usual treatment has faltered or has been linked to unacceptable adverse effects until better research are available.
Treating the underlying problem is prudent when another disease or exposure has caused the vasculitis. An illustration of this is the treatment of hepatitis C-associated cryoglobulinemia, which is best handled by combining corticosteroids to lessen acute inflammation and antiviral therapy to get rid of the virus.
As previously indicated, withdrawal of the suspected medicine can be done when drug-induced vasculitis is suspected, but only with the treating physician's approval.
Many types of vasculitis, such as PAN, MPA, CSS, PACNS, or GCA, may need treatment for about 2 years before therapy can be gradually discontinued. Other disorders (such as WG and TA) frequently need therapy for longer durations or are more likely to relapse if treatment is stopped. The appropriate length of therapy for every individual patient must be determined under the careful observation of the treating physician. Although diagnosing and treating the many varieties of vasculitis can be difficult, with the help of a skilled and meticulous doctor, patients can expect the best results.
