What are the other Names for this Condition? (Also known as/Synonyms)

• Allergic Angiitis
• Allergic Granulomatous Angiitis
• Churg-Strauss Vasculitis

What is Churg-Strauss Syndrome? (Definition/Background Information)

• Churg-Strauss Syndrome is a rare autoimmune disorder affecting small blood vessels and airways of the lungs.
• It causes allergic rhinitis, asthma, and increased eosinophils in blood (eosinophilia). Different individuals can have different set of signs and symptoms.
• It cannot be transmitted from person to person. It cannot be inherited from parents or transmitted to children.
• It can be confused with a disorder called polyarteritis nodosa with which it shares some similarities. Churg-Strauss Syndrome is different from Polyarteritis Nodosa.

Churg-Strauss Syndrome can occur in three stages:

• First stage (allergic stage) is called the prodromal stage, which is characterized by asthma and allergic rhinitis due to inflammation of airways of the lungs.
• The second stage (Eosinophilic stage) is characterized by increased number of eosinophils in the blood called hypereosinophilia. This increased number of eosinophils (termed as “peripheral eosinophilia”) causes tissue damage in the lungs and gastrointestinal tract.
• The third stage (Vasculitis stage) is characterized by inflammation in the blood vessels called Vasculitis. This Vasculitis disrupts blood in different types of organs such as lungs, kidney, heart, peripheral nerves and brain that may lead to a severe and life threatening situation. This stage can eventually lead to necrosis and is potentially life threatening.

Not all individuals will have all the three stages as described above. 

Who gets Churg-Strauss Syndrome? (Age and Sex Distribution)

• Both males and females are affected by Churg-Strauss Syndrome.
• No specific racial, ethnic or geographical predisposition or restriction is seen
• Usually the condition diagnosed between 35 to 50 years
• It is a very rare disorder with estimated 2 to 5 new cases per year per 1 million people.

What are the Risk Factors for Churg-Strauss Syndrome? (Predisposing Factors)

• Churg-Strauss Syndrome is common in individuals who have history of allergic rhinitis and asthma
• Family history (meaning having a family member with Churg-Strauss Syndrome does not increase the risk

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Churg-Strauss Syndrome? (Etiology)

• The cause of Churg-Strauss Syndrome is unknown. 
• Currently active Research is being performed to determine the cause. Some scientists believe that it is caused by abnormal immune system after a bacterial or a viral infection. 

What are the Signs and Symptoms of Churg-Strauss Syndrome? 

The signs and symptoms of Churg-Strauss Syndrome occurs in three stages and are described as follows:

Stage 1 is the Allergic stage is also called prodromal stage and  is characterized by :

• Asthma
• Allergic rhinitis
• Nasal polyps
• Sinusitis
• Frequent running nose 

The second stage is called Eosinophilic stage. The second stage (eosinophilic stage) is characterized by increased number of eosinophils in the blood called hypereosinophilia. This increased number of eosinophils causes tissue damage in the lungs and gastrointestinal tract. The symptoms during this stage include:

• Night sweats
• Fever
• Abdominal pain
• Joint pain
• Skin rashes
• Body aches
• Gastrointestinal bleeding
• Asthma
• Cough 

The eosinophilic stage can last months or years, and its symptoms can disappear, only to return later. Individuals may experience the third stage simultaneously.

The third stage (Vasculitis stage) is characterized by inflammation in the blood vessels called Vasculitis. This Vasculitis disrupts blood in different types of organs such as: 

• Lungs
• Kidney
• Heart
• Peripheral nerves
• Brain (which may lead to severe and life threatening situation)

During this stage the symptoms may include: 

• Chest pain,
• Abdominal pain due to decreased blood flow to various organs
• Perforation of intestines
• Appendicitis
• Pain in abdomen due gallbladder inflammation
• Severe damage to heart muscles due to myocarditis

In many cases, damage to the kidney may not be readily apparent. Symptoms due to kidney damage occur after the kidneys have been severely damaged.

How is Churg-Strauss Syndrome Diagnosed?

• A thorough physical examination and complete medical history

There are sets of criteria that need to be met before a diagnosis of Churg-Strauss Syndrome is made. There are six listed criteria and in order to diagnose at least 4 of the 6 criteria have to be present. The diagnosis can be challenging at times and requires coordination between different groups of physicians.

The American College of Rheumatology 1990 criteria for diagnosis of Churg-Strauss Syndrome lists the following six criteria:

• Asthma
• Eosinophils greater than 10% of a differential white blood cell count
• Presence of Mononeuropathy or polyneuropathy
• Non-fixed pulmonary infiltrates
• Presence of paranasal sinus abnormalities
• Histological evidence of extravascular eosinophils

For diagnostic purposes, an individual has Churg–Strauss syndrome (CSS) if at least 4 of these 6 criteria are present. The presence of any 4 or more of the above 6 criteria yields a sensitivity of 85% and a specificity of 99.7%.

• A high percentage of individuals have a history of chronic and usually severe asthma History ofasthma. Asthma usually is a new symptom in most individuals. In some individuals there may be an increase in severity of a pre-existing asthma.
• Increased number of eosinophils in the blood called hypereosinophilia. This increased number of eosinophils (termed as “peripheral eosinophilia”) is usually greater than 10% on a differential of total white blood cells.
• Damage to nerves with nerve symptoms called either Mononeuropathy or polyneuropathy. Mono neuropathy means that a single nerve is damaged whereas poly neuropathy means that more than one nerve is damaged. More the number of nerves damaged would result in greater neurological signs and symptoms
• A chest X-ray can identify inflammation of the lungs causing migratory episodes of pneumonia like changes. This means the inflammation in the lungs comes and goes. The region of lungs affected also changes with time. This can be demonstrated when periodic chest X-rays are performed.
• Frequent episodes of sinusitis, running nose, headaches and abnormalities in the x ray of sinuses of face due to inflammation and densities in sinus cavities (means that tissue appears dense on radiology images when examined by a radiologist)
• Diagnostic tissue biopsies and analysis of the affected tissue showing increased eosinophils (tissue eosinophilia). This is a finding that is determined by a pathologist who examines the tissue under a microscope.
• Blood test for autoantibodies: Half of the patients with Churg-Strauss Disease have positive blood test for autoantibodies called anti-neutrophil cytoplasmic antibodies (ANCA) which are expressed in a pattern called “p-ANCA”. This specific pattern helps the healthcare providers in arriving at the diagnosis. Having a positive blood test is very helpful. A negative blood test for these specific autoantibodies does not mean that individual does not have Churg-Strauss disease.   In such case a scenario the healthcare provider relies on other testing to arrive at a diagnosis
• A biopsy of the tissue: A biopsy of the tissue is sent to the laboratory where a pathologist examines the nodule under microscope to arrive at a conclusion that aids in definitive diagnosis. A biopsy is not needed for a definitive diagnosis and often may not be performed.
• Urine test for presence of blood and protein
• X rays and CT scans of affected areas may be performed depending on the types of symptoms and signs.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis. 

What are the possible Complications of Churg-Strauss Syndrome?

Possible complications of Churg-Strauss Syndrome include:

• Due to decreased blood flow to various organs
• Perforation of intestines
• Appendicitis
• Pain in abdomen due gallbladder inflammation and severe damage to heart muscles due to myocarditis
• Damage to heart muscle due to inflammation is called myocarditis

How is Churg-Strauss Syndrome Treated?

• Treatment for Churg–Strauss syndrome includes medications such as: glucocorticoids (such as prednisolone), Azathioprine and Cyclophosphamide (which decreases the immune response and inflammation) 

The above medications have to be given lifelong in some cases. In cases of complications such as perforation of intestines, severe bleeding in the intestines, appendicitis, inflammation of gall bladder and collection of fluids around the heart, may often require surgery.

How can Churg-Strauss Syndrome be Prevented? 

Currently there are no methods to prevent Churg–Strauss syndrome. 

What is the Prognosis of Churg-Strauss Syndrome? (Outcomes/Resolutions) 

The prognosis depends on the risk stratification of Churg–Strauss syndrome developed by The French Vasculitis Study Group. According to this system there is a five-point system ("five-factor score" or FFS) that uses the presence of signs and symptoms to predict the risk of death in Churg–Strauss syndrome. These five factors include:

• Reduced renal function (creatinine >1.58 mg/dL or 140 μmol/l)
• Proteinuria (>1 g/24h)
• Gastrointestinal hemorrhage
• Infarction
• Pancreatitis
• Involvement of the central nervous system
• Cardiomyopathy

The lack of any of these factors indicates that an individual has a mild form of Churg–Strauss syndrome and a five-year mortality rate of 11.9%.

The presence of 1 factor indicates severe disease, with a five-year mortality rate of 26%,

If 2 or more factors are present then it indicates a very severe disease with a expected five year mortality rate of 46%.

Additional and Relevant Useful Information for Churg-Strauss Syndrome:

It was first described by and named after two pathologists scientists; Jacob Churg (1910–2005) and Lotte Strauss (1913–1985). The ICD-10 codes for Churg–Strauss syndrome is - ICD-9447.6