Haemoglobin estimation
Normal and Abnormal Types of Hb
Normal Types
Hb A (2 alpha 2 beta)
Hb A2 (2 alpha 2 delta)
Hb F (2 alpha 2 gamma)
Abnormal Types
Hb C
Met Hb
Sulf Hb
Glycosylated Hb (HbA1c)
Hemoglobin Electrophoresis
Hemoglobin electrophoresis is probably the most useful laboratory
method for separating and measuring normal and some abnormal Hb.
Through electrophoresis, different types of Hb are separated to form a
series of distinctly pigmented bands in a medium (cellulose acetate or
starch gel). Results are then compared with those of a normal sample.
Hb A (same as Hb A1), Hb A2, Hb S, Hb C, and Hb F are routinely
checked.
This test by measuring the different types of Hb is used to detect
normal and abnormal types of hemoglobin, to aid in the diagnosis of
thalassemia and to aid in the diagnosis of sickle cell disease or trait.
Methods for Hb estimation
Sahli’s Method
Cyanmet Haemoglobin method
Spectrophotometer
Direct Matching
Haden Haussen Method
Colorimetric Methods
Gasometric Methods
Specific Gravity Methods
Chemical Methods
Hematology Analyzer
Sources of Error
Inadequate mixing of blood sample
Incorrectly calibrated pipettes
Incomplete conversion of Hgb to cyanmethemoglobin
High concentration of WBC's or platelets
Does not measure sulfhemoglobin
Normal hemoglobin Ranges
14 - 18 g/dl ……….men
12 - 16 g/dl ……….. Women
11.5-13.5 g/dl ……..Child
17-22 g/dl…………….newborn
12-16 g/dl……………Dogs
10-15 g/dl……………..cats
11-19g/dl…………….horses
8-17 g/dl………………poultry
8-15 g/dl ……………..cow
9-15 g/dl ……………..sheep
8-12 g/dl ……………..goat
10-16 g/dl …………….pig
Increase Hb
g) Smokers may have elevated haemoglobin levels.
h) Adaptation to high altitudes.
i) Testosterone supplementation
j) Increased RBC formation associated with excess erythropoietin.
Erythropoietin (EPO) is a hormone growth factor for red blood cells in the bone
marrow.
A synthetic erythropoietin (Epogen) has been made that is used to treat anaemia
due to kidney failure or chemotherapy. However, although it is illegal, it is also
used by athletes to increase their endurance.
Increased hemoglobin may indicate:
a) Dehydration - This can cause a falsely high hemoglobin reading
which disappears when proper fluid balance is restored, eg, as in severe
diarrhea.
b)Polycythemia vera - a condition in which there is a long-term
increase in red blood cells.
c) Macrocytosis - a situation where the red cells are larger than normal.
e) Congenital heart disease
f) Lung Diseases e.g. Emphysema, Severe asthma, pulmonary fibrosis,
scarring of the lung.
Lung failure of the right side of the heart caused by prolonged high
blood pressure in the pulmonary artery and right ventricle of the heart.
Hb decrease
A slow progressive decline in hemoglobin in people
with AIDS due to a decline in the number of RBCs
produced in the bone marrow.
Any drug which causes a suppression of the bone
marrow will decrease the hemoglobin levels
Erythropoietin: EPO has enabled many people to stay
on bone marrow suppressive drugs without the need
for transfusions.
Decreased hemoglobin
a) Anemia of various types.
b) Blood loss from traumatic injury, surgery, bleeding colon
cancer.
c) Gastrointestinal tract diseases resulting in blood loss e.g.
parasitic infections, colitis, haemorrhoids, ulcers.
d) Erythropoietin deficiency e.g. from kidney disease.
e) Red blood cell destruction associated with transfusion
reaction
f) Lead poisoning
Decreased hemoglobin
g) Malnutrition and the associated nutritional deficiencies
of iron, folic acid, vitamin B-12 & vitamin B-6
h) Bone marrow disorders eg. cancer or suppression by
chemotherapy drugs.
i) Abnormal hemoglobin eg. sickle cell anemia &
thalassemia.
j) Women may have temporary decreases during menstrual
periods and pregnancy.
