Eosinophilia
From Wikipedia, the free encyclopedia
| ICD-10 | D72.1 |
|---|---|
| ICD-9 | 288.3 |
| DiseasesDB | 4328 |
| eMedicine | med/685 |
Eosinophilia is the state of having high eosinophil granulocytes in the blood. The reference range is between 0 and 0.5 x 109 eosinophils per litre of blood. Blood eosinophilias are classified in reactive (roughly, allergic) and non reactive eosinophilias
- Diagnostic procedure and investigations for blood eosinophilia
Diseases that feature eosinophilia:
- Parasitic infections
- Allergic disorders
- Some drug reactions
- In cholesterol emboli
- Churg-Strauss syndrome
- Some forms of chronic myeloid leukaemia
- Hodgkin's Disease
- Addison's disease
The release of interleukin 5 by T cells, mast cells and macrophages stimulates the production of eosinophils.
When does Eosinophilia occur?
Eosinophilia occurs in a wide range of conditions. Its commonest causes in the UK are allergic diseases such as asthma and hay fever, whereas worldwide the main cause is parasitic infection. It can also occur in relation to common skin diseases, medicine reactions, and parasitic infections. Other rarer causes include:
- 1. Lung diseases, eg Loeffler's syndrome
- 2. Vasculitis (inflammation of blood vessels), eg Churg-Strauss syndrome
- 3. Some tumours, eg lymphoma
- 4. Liver cirrhosis
- 5. Some antibody deficiencies; not typically AIDS
- 6. Other rarer skin diseases, eg dermatitis herpetiformis
- 7. Uknown causes, labelled hypereosinophilic syndrome.
How does Eosinophilia occur?
Increased numbers of eosinophils are produced to fight off allergic disease or parasitic infections. This is helpful in combating parasitic infections but not in cases of allergic diseases as they accumulate in tissues and cause damage. For example, in asthma, eosinophilia causes damage to the airways of the lung.
What are the symptoms of eosinophilia?
The symptoms of eosinophilia are those of the underlying condition. For example, eosinophilia due to asthma is marked by symptoms such as wheezing and breathlessness, whereas parasitic infections may lead to abdominal pain, diarrhoea, fever, or cough and rashes.
Medicine reactions often give rise to skin rashes, and they often occur after taking a new drug.
Rarer symptoms of eosinophilia can include weight loss, night sweats, lymph node enlargement, other skin rashes, and numbness and tingling due to nerve damage.
Hypereosinophilic syndrome
Hypereosinophilic syndrome is a condition where there is no apparent cause for eosinophilia.
This rare condition can affect the heart, resulting in heart failure with breathlessness and ankle swelling, cause enlargement of the liver and spleen, resulting in swelling of the abdomen, and give rise to skin rashes.
How is Eosinophilia diagnosed?
Eosinophilia in the bloodstream is diagnosed from a simple blood test. Tissue eosinophilia is diagnosed by the examination of the relevant tissue. For example, a piece of skin tissue can be removed (a skin biopsy) and examined under a microscope.
What can a doctor do?
Once a diagnosis has been made your family doctor can help to establish the cause of the condition. Simple skin or blood tests may be performed to confirm specific allergies, such as pollen or dust mite allergy. Parasitic infection can be determined by analysing blood and stool samples.
You may also be asked whether you are taking any new medicines in case it is the result of a side effect, and about foreign travel for possible parasitic infection.
A pet dog can occasionally be a source of a parasitic infection called Toxocara canis.
When to refer to a specialist?
If your GP cannot make a diagnosis, then you may be referred to a hospital specialist. The choice of specialist will depend on your symptoms. But it will usually be a haematologist (blood disorder specialist).
Further tests may include blood tests to measure levels of antibodies, chest X-ray, CT scans of the chest and abdomen, skin or lung biopsies, examination of the bone marrow, and bronchoscopy.
Treatment
Treatment tackles the underlying cause of the condition, whether it is an allergy, a medicine reaction, or a parasitic infection. These treatments are usually effective, and fairly non-toxic.
Treatment for hypereosinophilic syndrome is oral corticosteroid therapy, usually starting with prednisolone (eg Deltacortril) at single daily doses of 30-60mg. If this is not effective, a chemotherapeutic agent is administered.
Living with eosinophilia
In most cases, when the cause of eosinophilia is identified, treatment significantly reduces the symptoms of the condition. Corticosteroids, both local (inhaled, topical), and systemic (oral, intramuscular, intravenous), are used to manage several allergic conditions and reduce the number of eosinophils.
In hypereosinophilic syndrome there is a high risk of damage to the heart and other major organs. In some cases a blood cell tumour known as a T-cell lymphoma may also develop, so patients must be carefully monitored.
