Complete blood count with Differential (CBC with DIFF)

Complete blood count provides information about blood cells as well as measurements looking at their sizes and shapes that can be used to determine the health of an individual. These include:

– White blood cells count: These fight infections.
– Red blood cells count: These carry Oxygen.
– Total Hemoglobin: This determines the capacity to carry oxygen.
– Hematocrit: This is a more accurate estimate of total hemoglobin.
– Platelet: This helps with clotting in case of bleeding.

Measurements provided here include:

– MCV: Average volume of red blood cell.
– RDW: Measures of the variability in the size of red blood cells.
– MCH: Average amount of Hemoglobin per single red blood cell.
– MCHC: Average concentration of hemoglobin per red blood cell.

White Blood Cells

White blood cell count is commonly ordered even though it has no value as a screening test.

White blood cells:
White blood Cells include
– Mostly Neutrophils that are the most common of the white cells (60-70%). Neutrophils in circulation are mostly mature cells and are involved primarily in fighting infections.                                                                                               – Lymphocytes (30-40%)
– Monocytes (2-8%)
– Eosinophils (1-4%)
– Band or Immature Neutrophils (0-3%). These appear with severe infections when there is the recruitment of neutrophils mature or immature in a massive scale. When there are more than 10% immature neutrophils in circulation it is called bandemia.

High White blood cells and in particular Neutrophils are seen in:

– Infections such as pneumonia
– Inflammation
– Smoking
– Medications such as steroids, lithium
– Exercise / Stress
– Leukemia/Cancer

Low White blood cells or Neutrophils are seen in:
– After infections with bacteria or viruses
– Medications such as Cancer drugs
– Immune related such as in Systemic Lupus
– Vitamin Deficiency such as Vitamin B12 deficiency
– Leukemia / Cancer

Red Blood Cells

Red Blood Cells carry oxygen and changes in the number of these cells can cause significant problems. Hemoglobin is a protein that carries oxygen from lungs to the body and brings back carbon dioxide from the body back to the lungs. Hemoglobin level gives an indication of blood’s ability to carry oxygen. Hematocrit gives a more accurate estimate of hemoglobin.

Red blood cells (RBCs), Hemoglobin and Hematocrit are decreased with:
– Iron deficiency Anemia
– Bleeding
– Kidney disease
– Cancer
– Medications
– Vitamin deficiency
– Radiation
– Pregnancy
– Overhydration

Red blood cells (RBCs), Hemoglobin and Hematocrit are increased with:
– Lung disease /Smoking
– Sleep Apnea
– Use of diuretics
– High altitude
– Anabolic steroids
– Cancer of kidney, liver, brain, adrenals
– Uterine fibroids
– Polycythemia

Platelets

Platelets are fragments of large cells called megakaryocytes that are involved in blood clotting.

High Platelet count is seen in:
– inflammatory diseases such as vasculitis, inflammatory arthritis
– Bleeding, iron deficiency, hemolytic anemia
– Trauma, burn, heart attack
– Chronic infections
– Allergic reactions
– Lymphoma, cancer
– Medications

Low Platelet count is seen in:
– Clumping. This results in falsely low platelet count
– Medications such as quinine, heparin, sulfa drugs such as Bactrim, antibiotics such as vancomycin, acetaminophen, NSAIDs like Naprosyn, Tagamet, cancer drugs
– Infections such as hepatitis C, HIV, Sepsis, mono, h.pylori, Babesia
– Toxic such as alcohol
– Immune related such as in Systemic Lupus, Antiphospholipid antibody syndrome, TTP,
– Vitamin Deficiency such as Vitamin B12 deficiency
– Pregnancy
– Cancer

Mean Corpuscular Volume (MCV)

Mean Corpuscular Volume (MCV) measures the volume of red blood cells using hematocrit and red blood cell count. It is an indication of the size of the red blood cells. The normal range is between 80 and 96 depending on the individual laboratory.

MCV is used along with Red Cell Distribution Width (RDW) in order to determine the cause of anemia. With the addition of RDW, Mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) is no longer clinically used because of their limitations.

MCV is elevated (greater than 96) in:
– Vitamin B12 deficiency (Elevated RDW)
– Folate deficiency (Elevated RDW)
– Medications: Methotrexate, Imuran, Hydroxyurea (Normal RDW)
– Alcohol (Normal RDW)
– Liver disease (Elevated RDW)
– Multiple Myeloma (Elevated RDW)
– Myelodysplastic syndrome (Elevated RDW)

MCV is normal (Between 80-96):
– Chronic disease (Elevated RDW)
– Renal failure (Elevated RDW)
– Sickle cell Anemia (Elevated RDW)
– Early Vitamin B12 and iron deficiency or mixed deficiencies (Elevated RDW)

MCV is low (less than 80) in:
– Iron deficiency (Elevated RDW)
– Toxins and drugs (Normal RDW)
– Thalassemia (Normal RDW)
– Myelodysplastic Syndrome (Elevated RDW)

RDW, MCH, MCHC

Red Cell Distribution Width (RDW) measures the variability in the size of red blood cells. This parameter can help distinguish the various causes of anemia along with Mean corpuscular volume (MCV). With the addition of RDW, Mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) are no longer clinically used because of their limitations.

Mean Corpuscular Hemoglobin (MCH) measures the average amount of Hemoglobin per single red blood cell. It was used in the past to determine the cause of anemia. But because of its limitations, Mean Corpuscular Volume or MCV along with Red Cell Distribution Width (RDW) have replaced MCH as means of determining the cause of anemia.

Mean Corpuscular Hemoglobin Concentration (MCHC) measures the average concentration of hemoglobin per red blood cell. It was used in the past to determine the cause of anemia. But because of its limitations, Mean Corpuscular Volume or MCV along with Red Cell Distribution Width (RDW) have replaced MCHC as means of determining the cause of anemia.