Q. I am 25 years old. I underwent a CBC yesterday. One month back I had red rashes with itching on my feet, legs and hands. My eosinophil count was 1050 and 16%. The doctor prescribed Zentel and Benocite Forte, which I took for one month. Yesterday my blood count showed 183 and 3% eosinophil, but lymphocytes were 49% (against a normal of 30-45%). I still have some red rashes on my chest and down chest. What is the cause for the rise in lymphocyte count? All other differential count and RBC/WBC are normal.
White blood cells in the blood (leukocytes) comprise granulocytes (cells with granules in their cytoplasm) and mononuclear cells. Granulocytes are of three types – neutrophils, eosinophils and basophils while mononuclear cells are lymphocytes and monocytes.
The normal total leukocyte (white blood cells or WBCs) count varies with the age of a person. It also has a diurnal cycle, i.e. counts vary during a 24 hour day. Normally, they range from 4000 to 10,000 per ml in an adult. Leukocytosis is an increase above the accepted normal range of total leukocytes while leukopaenia is a decrease below the accepted normal range. Usually only one type of cell is responsible for this increase or decrease, but there may be a simultaneous increase / decrease in several cell types. The counts may go up due to an increase in any component of the white cells, i.e. neutrophils (called neutrophilia), lymphocytes (called lymphocytosis), monocytes (called monocytosis), eosinophils (called eosinophilia) or basophils (called basophilia). In contrast, a fall in these cells is referred to as neutropaenia, lymphopaenia, monocytopaenia, etc. This can be judged by a differential leukocyte count. The range of each of these cells also varies with the age of an individual. There are numerous causes for an increase or decrease in neutrophils, lymphocytes, etc.
Eosinophils are a type of WBCs produced in the bone marrow that contain proteins that contribute to the immunologic responses against infectious disease agents and to tissue damage in allergic and autoimmune diseases. Normally, the absolute eosinophil count in the blood is around 500 per microlitre but it can increase in: allergic conditions (asthma, allergic rhinitis, drug reactions), infectious diseases (especially worm infestation), some connective tissue diseases, malignancies, etc.
Your eosinophilia was likely a response to the rashes (the cause of which should be determined) and the counts have fallen as a response to treatment.