A high level of disease-fighting white blood cells known as eosinophils in the blood... An eosinophil count is a blood test that measures the quantity of eosinophils in your body. Abnormal eosinophil levels are often discovered as part of a routine complete blood count (CBC) test

Explanation:
Allergic asthma is characterized by inflammation and narrowing of the airways in response to allergens, leading to symptoms such as wheezing, coughing, and shortness of breath. A blood test can be useful in diagnosing and monitoring asthma, as it can provide information about the immune response and the presence of inflammation in the body.

In this case, the blood test showed an abnormal increase in the number of leucocytes, which are white blood cells responsible for fighting off infections and regulating the immune response. The specific type of leucocytes that displayed an abnormal increase in number in Meghna's blood test is eosinophils.

Role of Eosinophils:
Eosinophils are a type of granulocyte white blood cell that play a crucial role in allergic responses and parasitic infections. They are primarily involved in combating multicellular parasites, such as helminths, by releasing toxic proteins and enzymes that can kill the parasites. Additionally, eosinophils are also involved in modulating the immune response and participating in allergic reactions.

Increased Eosinophil Count in Allergic Asthma:
In the context of allergic asthma, an increase in eosinophil count is commonly observed. This is because eosinophils are recruited to the lungs in response to the inflammation triggered by allergens. Once in the lungs, eosinophils release various inflammatory mediators, including cytokines, chemokines, and leukotrienes, which contribute to the asthma symptoms and the ongoing inflammation.

Diagnostic Significance:
The abnormal increase in eosinophil count in Meghna's blood test is indicative of ongoing allergic inflammation and can help confirm the diagnosis of allergic asthma. Monitoring the eosinophil count over time can also be useful in assessing the effectiveness of treatment and managing the disease.

Conclusion:
In summary, an abnormal increase in eosinophil count is commonly observed in allergic asthma. Eosinophils play a crucial role in allergic responses and their recruitment to the lungs contributes to the inflammation and symptoms associated with allergic asthma. Monitoring the eosinophil count can aid in diagnosis, treatment, and management of the disease.