By Dr. Manal Basyouni

Dr. Manal Basyouni

Heme consists of a Porphyrin ring coordinated with iron. It is found mainly in hemoglobin but also present in myoglobin and cytochrome.

Normal Hb Values:



Male: 14 -18 g%.



Female: 12 -16 g%.

Sample: whole blood (anticoagulant as EDTA may be added).

Dr. Manal Basyouni



Principle

: 1 -

Hb

is oxidized HB by

Potassium ferricyanide {K Fe (CN)} into Met-haemoglobin

HB (Fe

+++ ).

HB (Fe

++ ) + K Fe +++ (CN) HB (Fe +++ ) + K Fe +++ (CN ) 2 Met-haemoglobin is converted into Cyanmet haemoglobin by Potassium cyanide.

HB (Fe +++ ) + K CN HB (Fe +++ ) CN 3 It m easured by photometer at 540 nm .

4- HB conc. = A sample ˟ 36.77 (g%) Or use standard curve for Cyanmet-haemoglobin Dr. Manal Basyouni

Principle of assay (Colorimetric Method)

: HB (Fe

++ ) Potassium ferricyanide (Fe +++ CN) Met-haemoglobin

HB (Fe

+++ ) Potassium cyanide (K CN) Cyanmet-haemoglobin HB (Fe +++ ) CN Measured by photometer at 540 nm Dr. Manal Basyouni

Diagnostic Significance of Hb



HB conc. is decrease in

:

1.

2.

Hemolytic anemias , e.g. thalassemias, Sickle cell anemia.

Iron deficiency anemia.

3.

4.

Megaloblastic anemia (folic acid or vit. B12 deficeincy).

Hemorrhagic anemias e.g. Vit. K deficiency, menorhagia, ankolystoma infection).

Dr. Manal Basyoun

i

•

HB conc. is increase in

:

1- Polycythemia (erythrocytosis).



Primary cause: Polycythemia Vera.



Secondary cause: cyanic heart diseases, smoking, tumors secreting erythropoitin.

2- Decrease blood volume : e.g. dehydration, vomiting, diarrhea, use of

diuretics.

Dr. Manal Basyouni