Lab Tests for Vasculitis

Vasculitis is a term that is used to describe a group of conditions characterized by inflamed blood vessels. If there is not a clear, obvious cause for the condition, then it is typically referred to as primary vasculitis. When there is a cause, it is called secondary vasculitis. There are a lot of things that can cause secondary vasculitis, such as allergic reactions to medication, infection with hepatitis C, auto-immune diseases such as rheumatoid arthritis, and even complications related to lymphoma or leukemia. 

Vasculitis can affect veins, arteries, and capillaries, resulting in narrowed vessels that limit the circulation of blood and can cause tissue or organ damage. A weakened vessel can lead to an aneurysm, which may, in turn, cause life-threatening internal bleeding. 

There are a lot of different kinds of vasculitis, and they are classified based on the size and type of the blood vessel affected. Understanding the different types and they’re sometimes confusing or nebulous symptoms is important for recognizing the condition so that people can get appropriate treatment. 

The Types of Vasculitis and their Symptoms 

Vasculitis is a systemic illness. This means that symptoms can often be non-specific. Some of the most common symptoms are easily confused with other diseases that cause inflammation, for example: 

  • Loss of appetite 
  • Fatigue 
  • Weight loss 
  • Aches and pains 
  • Fever 

The symptoms might come on suddenly or could gradually surface over a period of several months. The order of onset, presentation, and type of symptoms can vary massively. Some people experience localized symptoms specific to the type of vasculitis that they are suffering from, and this can help to characterize the condition more clearly in some cases, but not everyone’s condition results in the same symptoms, so diagnosis is not easy. 

Laboratory Test

Complete Blood Count (CBC) testing is a test that checks the red blood cells and hemoglobin and can help to diagnose anemia. It also looks at the white blood cell count, which may be increased if someone has an infection, or reduced if they have had treatments that may weaken the immune system. Some types of vasculitis can cause increased white blood cell counts. One example is Eosinophilic Granulomatosis with Polyangiitis (EGPA). 

C-reactive protein (CRP) testing can identify cases of inflammation within the body. 

Erythrocyte sedimentation rate (ESR) testing is another test that can detect inflammation, and it can identify certain types of vasculitis,  with this test also detects the presence of inflammation and can be increased in several types of vasculitis, such as microscopic polyangiitis and granulomatosis with polyangiitis being one example. 

Creatinine testing is used to assess the functioning of the kidneys. Reduced kidney function is sometimes present in vasculitis. 

Liver panels help to determine if liver function is impaired. 

Urinalysis looks for red blood cells and protein in the urine, which can be a sign of kidney inflammation. 

Anti-neutrophil cytoplasmic antibody (ANCA) testing looks for a marker that can be often be found in patients with certain systemic vasculitis diseases. 

Complement is a test for the part of the immune response, which is something that is often reduced in people with vasculitis.