Hemoglobin
Protein in red blood cells that oxygenates the body’s tissues
Causes of Low Hemoglobin
- Anemia resulting from:
- Trauma
- Blood loss
- Nutritional deficiency
- Vitamin B12
- Folate
- Iron
- Genetic disorders
- Sickle cell
- Thalassemia
In pregnancy, the lower limit is usually decreased to 10 g/dL to accommodate physiological plasma expansion. A low Hb is called anemia
Hb is also used to grade the severity of anemia
Causes of elevated Hemoglobin
erythrocytosis is defined as a high Hb.
Polycythemia vera
* Lung disease
* COPD
* Emphysema
* Pulmonary fibrosis
* Heart disease
Hematocrit
Hematocrit (Hct) is the percentage volume of red blood cells (RBC) in the blood calculated with RBC and mean corpuscular volume (MCV): Hct = RBC x MCV/10.
Measurement of the percentage of blood volume containing red blood cells
Normal Range
* Female patients: 36%-44%
* Male patients: 41%-50%
Causes of Low Hematocrit
- Blood loss
- Depression of red blood cell production in the bone marrow
- Nutritional deficiency
- Vitamin B12
- Iron
- Folate
Similarly to Hb, Hct is reduced in anemia, and is influenced by changes in plasma volume
Causes of Elevated Hematocrit
- Dehydration
- High altitude
- Smoking
- Congenital heart disease
increased in erythrocytosis,
Leukocytosis and neutrophilia can be caused by
infection,
myeloproliferative disorders,
inflammation,
and medications
Leukocytopenia and neutropenia can result from
nutritional deficiency,
autoimmune disease,
bone marrow infiltration (i.e., leukemia or
myelodysplastic syndrome),
radiation,
myelosuppression due to medications
Unconjugated bili is? Elevated in?
bound to albumin, insoluble
Increased red blood cell destruction (hemolysis) or liver’s inability to process it (e.g., Gilbert’s Syndrome)
Direct Bili measures? Elevated in?
Direct bili (post liver, soluble)
Bile duct obstruction(like gallstones or pancreatic issues) or liver diseases (hepatitis), preventing proper excretion
Liver Function Tests
ALT
AST
GGT
Medications Affecting Liver Enzyme Levels
Certain medications can cause elevated liver enzyme levels, particularly AST and ALT. Common examples include:
* Statins
* Phenytoin (Dilantin)
* Carbamazepine (Tegretol)
* Isoniazid (Niazid)
* Methotrexate (Rheumatrex)
* Acetaminophen overdose (Tylenol)
* Amiodarone (Pacerone)
The standard CBC includes a
measured red cell count (RBC), hemoglobin (Hb), and hematocrit (Hct), calculated red cell indices, a platelet count, and a white cell count (WBC). Most analyzers now also automatically generate a leucocyte differential.
—> CBCD
Mean corpuscular volume (MCV)
defines the average volume of the red blood cells present
MCV is commonly used to classify anemias as microcytic (low MCV), normocytic (normal MCV), or macrocytic (high MCV)
Elevated MCV
elevated in the setting of:
Red cell agglutination, where doublet erythrocytes are automatically counted as one
Hyperglycemia occurs when an excess of glucose causes hypertonic erythrocytes to swell, increasing RBC volume within the counting medium.
Hypernatremia is due to the swelling of hypertonic erythrocytes.
Hyperleucocytosis, where the larger white cells are counted as red cells when calculating mean cell volume.
Mean corpuscular hemoglobin (MCH) vs MCHC
MCH: quantifies the amount of hemoglobin per red blood cell
MCHC: MCHC is the mean hemoglobin concentration per unit volume of red blood cells,
Increased MCHC can be due to
red blood cell morphology abnormalities, such as spherocytosis and xerocytosis or hemoglobinopathies.
More commonly, high MCHC represents an artifact such as in the following:
Lipemia, which spuriously elevates Hb and consequently MCHC
Hemolysis, where Hb is disproportionally elevated to Hct within the sample
Red cell agglutination, which spuriously lowers the red cell concentration and elevates MCV
Leukocytosis, which spuriously elevates MCV
Hyperbilirubinemia, which spuriously lowers Hb
Leukopenia is
defined as a low WBC and may be due to reduced production, increased utilization, or increased destruction of white blood cells. A spurious leukopenia may occur due to white blood cell clumping.
An elevated white blood cell count is called
leukocytosis and may be caused by an inflammatory stressor or myeloproliferative pathology. A spurious leucocytosis may occur in the setting of:
Reticulocytosis, where nucleated red blood cells are counted as white blood cells
Platelet clumping, where aggregate platelets are counted as white blood cells
Fibrin clumps
Cryoproteinemia
Identification of a WBC abnormality is followed by an assessment of
the white cell differential to identify which white blood cell types are affected. The differential may be reported as a percentage of the total WBC or as an absolute count for each mature white cell typ
Neutrophilia
infection, trauma, tissue necrosis, physical or emotional stress, smoking, myeloproliferative disease, chronic inflammatory disease (such as inflammatory bowel disease, systemic lupus erythematosus, and rheumatoid arthritis), vasculitides, chronic hepatitis, diabetic ketoacidosis, acute gout, congenital conditions (such as Down syndrome and hereditary idiopathic neutrophilia), blood loss, hemolytic anemia, obesity, pregnancy, or medications.
Neutropenia
bone marrow failure (due to myeloproliferative diseases, lymphoproliferative disease, metastatic malignancy, myelodysplasia or irradiation), megaloblastic anemia, hereditary, autoimmune disease (such as systemic lupus erythematosus and rheumatoid arthritis), hypersplenism, hemodialysis, viral infection (such as cytomegalovirus, measles, rubella, human immunodeficiency virus, Dengue fever, infectious mononucleosis), bacterial infections (such as typhoid fever or septicemia), protozoal infections, idiopathic, or drug-induced.
Lymphocytosis causes
Lymphocytosis, which refers to an increase in the lymphocyte count, may be due to viral infection, pertussis, toxoplasmosis, tuberculosis, brucellosis, hyposplenism, or lymphoproliferative disease.
Lymphocytopenia causes?
Lymphocytopenia, which refers to a decrease in the lymphocyte count, may be due to viral infection, bacterial infection, autoimmune disease (such as systemic lupus erythematosus, rheumatoid arthritis, Sjogren syndrome, and inflammatory bowel disease), malignancy, myeloproliferative disease, lymphoproliferative disease, primary immunodeficiency diseases or medications
