‘Complete blood count’

WELLNEWS

Victor Dumaguing

In most laboratory requests, it is written as CBC, which a lot of patients, even professionals-except perhaps those in health sciences, take the letter “c” to mean “complete; thus patients who gave 5ml of their blood-venous- go home thinking that the results would include their blood levels of sugar, cholesterol, uric acid, BUN, creatinine etc and be disappointed of the “incomplete results.”
    Most doctors or their medical secretaries write the words, “cbc differential” if they want to know the immune capabilities of the patient in terms of his/her white blood cells-soldiers of the body- with the word “differential” meaning how much each of the different leukocytes are there per 100 white blood cells counted.
    An adult human has 5000 ml of blood within his/her circulatory system, some amounts of the 5 liters are extracted depending on the clinical needs of the patient. For patients in serious conditions in which there is a big concern about the relationship off oxygen and carbon dioxide affecting the ph of the blood, the doctor would request ABG-arterial blood gases; the sample is carefully extracted from arteries- radial in the wrist, femoral in the groin and at times, carotid in the neck.
    In medical missions sponsored by civic organizations with the participation of generous pharmaceutical companies, the so-called screening laboratory tests-usually for blood sugar, cholesterol, triglycerides, uric acid etc, blood samples are for the most part done thru aseptic, sterile finger pricking –capillary blood- by the doctor or medical technologists or a trained health professional, with the results available after a few minutes, with the appropriate prescription made immediately.
    For CBC differential, venous blood is extracted from the vein in the ante-cubital area, or the area opposite the elbow. Normal WBC is 5000-10,000 cu mm, neutrophils 60-65, lymphocytes 25-30, monocytes 0-2, basophils 0-1, eosinophils 2-5 with slight variations but the total should always be 100 white blood cells counted. 
    At this juncture, it must be emphasized that different laboratories have normal values depending on their unit measurements; example, some use the mo don’t be surprised if the normal WBC count is from 4.0-11.0 in your result, the good thing about laboratory results now include the “normal ranges” of results whether white blood cells sugar, cholesterol and other clinical parameters.
    An elevated or high WBC count means “infection”; so the “differential would provide useful information. A High WBC, and neutrophils-also called PMN for polymorphonuclears- indicate an “acute” infection- infection which has a sudden onset, meaning earlier the patient is well, the all of a sudden, he/she is not well, example is a pupil caught in the rain going home and after a few hours, complains of sore throat, difficulty of swallowing and starts running a fever. A doctor consult yields big tonsils, with a diagnosis of “acute tonsillitis. Our professor in microbiology had emphasized that the level of WBC is a reflection of the virulence or pathogenicity of the microbe, while the level of neutrophils indicates the ability of immune system of the patient to cope up with the infection, thus the presence of young neutrophils in the blood- stabs and bands- means the body is trying its best to mount a defensive response.
    Lymphocytosis or elevated levels of lymphocytes-smallest white blood cells- means that the patient is suffering from chronic- long standing lingering illness- an example is tuberculosis, leprosy or in certain cases, viral infections.
Monocytes-the biggest WBC- with is unique horse-shoe or kidney-shaped form- is within normal levels in most microbial infections, except in certain rare forms of leukemia.
    Basophils too should normally 0-2 in most CBC differential; with the added fact that, aside from mast cells, basophils could also be a source of histamine.
    Eosinophils deserve some focus because an elevated level should make the doctor ask questions as to whether the person has some allergies to food/meds, asthma, allergic rhinitis, eczema/atopic dermatitis and with a lot of tact and diplomacy, request for a stool exam because the patient might be having helminthiasis, that’s parasitism in simple terms, yes, worms.
    By the way, the complete blood count differential request, does NOT include anemia concerns-red blood cell, hemoglobin hematocrit- and for those worried about dengue, chikungunya- NOT platelet count.
    Dear readers, this article is for general information only and does not claim to be the standard by which your lab results should be evaluated for or against. In clinical practice, there are myriad variations and combinations in the ratio of different white blood cells or leukocytes depending on the peculiar health status of the patient. Thus, an open, honest candid communication between you and your family physician is of paramount importance.