الواقع والحياد
14-09-2006, 02:12 PM
Erythrocyte Sedimentation Rate;
It is the gravitational settling of erythrocytes in diluted human plasma over a specified time period.
Factors affecting the ESR:
A-Effect of plasma protein:
Increased in the concentration of fibrinogen and Immunoglobulins due to tissue injury will increase rouleaux formtion and hence the rate of sedimentation.plasma albumin retards sedimentation of RBCs.
B-The RBC size and number:
The size and number of RBCs that show alterations in their bioconcavity, like spherocyte and sickle cells, usually do not exhibt increase rate, unless there is severe anemia. Increase red cell mass will retard the sedimentation rate e.g. polycythemia.
C-Technical factors
§ Perpendicularity of sedimentation tube, slight deviations from the absolute. Vertical can increase the result.
§ Temperature (RT 18-25 C) higher temperature cause false high results due to reduction in plasma viscosity (direct sun light).
§ Vibration cans reduce the ESR.
Sedimentation Phases:
1. The initial lag phase
2. The phase of rapid RBC falling.
3. The packing phase .
General Application of ESR:
As an indication of the presence of active disease
High ESR
§ Tuberculosis
§ Dissemenated lupus erythromatosis
§ Rhaematic arthritis
§ Malignancy
§ Anemia
Low ESR
§ Polycythemia
§ Anemia like sickle celland thalassaemia
§ Hypofibrinogenemia
§ Congestive cardiac failure
Referance Range:
Adult females 0-20 mm/h
Adult males 0-15 mm/hr
Children(<10) 0-10 mm/hr
____________________________________________
thanks .....
It is the gravitational settling of erythrocytes in diluted human plasma over a specified time period.
Factors affecting the ESR:
A-Effect of plasma protein:
Increased in the concentration of fibrinogen and Immunoglobulins due to tissue injury will increase rouleaux formtion and hence the rate of sedimentation.plasma albumin retards sedimentation of RBCs.
B-The RBC size and number:
The size and number of RBCs that show alterations in their bioconcavity, like spherocyte and sickle cells, usually do not exhibt increase rate, unless there is severe anemia. Increase red cell mass will retard the sedimentation rate e.g. polycythemia.
C-Technical factors
§ Perpendicularity of sedimentation tube, slight deviations from the absolute. Vertical can increase the result.
§ Temperature (RT 18-25 C) higher temperature cause false high results due to reduction in plasma viscosity (direct sun light).
§ Vibration cans reduce the ESR.
Sedimentation Phases:
1. The initial lag phase
2. The phase of rapid RBC falling.
3. The packing phase .
General Application of ESR:
As an indication of the presence of active disease
High ESR
§ Tuberculosis
§ Dissemenated lupus erythromatosis
§ Rhaematic arthritis
§ Malignancy
§ Anemia
Low ESR
§ Polycythemia
§ Anemia like sickle celland thalassaemia
§ Hypofibrinogenemia
§ Congestive cardiac failure
Referance Range:
Adult females 0-20 mm/h
Adult males 0-15 mm/hr
Children(<10) 0-10 mm/hr
____________________________________________
thanks .....