الطب المخبري

📲 Sickling test
•┈┈┈❈••✦✾✦••❈•┈┈┈•
➡️Reagents: -
Na-meta-bisulfate powder.

🔄Procedures:

♻️First preparation of Na-meta-bisulfate
1. Prepare 2% of Na-meta-bisulfate solution
2. Dissolve 2 gram of Na-meta-bisulfate in 100ml D.W
3. This solution, if stored at 3º or 4ºC remains effective for about one week.
4. Stable for 8 hr at room temperature 
♻️Second sickle cell test
1. Place a small drop of capillary blood or vines in the center of a slide.
2. Add an equal drop of the fresh sodium met-bisulfite solution.
3. Mix carefully and cover with a cover slide with petroleum jelly, make sure that no air bubbles form.
4. Place the slide in a wet chamber.
5. Examine under the microscope after 15 minutes using the 40 x objective.
6. The test is negative if the red cells remain round.
7. The test is positive if the cells become sickle-shaped, or banana-shaped. 

↪️ Limitations/ Interfering substance
1. This test should not perform on infant less than six months old
2. Sickling of red blood cells is maximum at 37°c and decrease as the temperature Lowers
3. Sever anemia will cause false negative result
4. Low Hb cause false negative: the use of packed cells will overcome this problem
5. Specimen with 25% Hb F present may cause false negative.
6. Blood from patients with polycythemia, multiple myeloma, dysglobulinemia may cause false positives
7. False-negative results may occur if:
a. Outdated reagents are used.
b. Concentrations of hemoglobin S are low.
c. Patients have moderate or severe anemia.
8. In all cases where abnormalities are indicated or suspected electrophoretic confirmation is recommended 

↪️ Results:
⤴️Negative result The erythrocytes remain round If the test is negative, re-examine the slide after a further 30 minutes, then after 2 hours and after 24 hours.
⤴️Positive result
1. The erythrocytes become sickle-shaped or banana-shaped often with spikes It is important to examine several parts of the preparation, as sickling can occur more quickly in one part than in another.
2. Do not mistake normal erythrocytes lying on their side created cells for sickle cells.

↪️Reporting result:
❇️Positive for sickle cell test.
❇️Negative for sickle cell test.
د. عبدالله احمد
•┈┈┈❈••✦✾✦••❈•┈┈┈•
@LabMed2016

www.tg-me.com/us/الطب المخبري/com.LabMed2016/32391

7.4K viewsedited  Dec 23, 2023 at 02:39

📲 Sickling test
•┈┈┈❈••✦✾✦••❈•┈┈┈•
➡️Reagents: -
Na-meta-bisulfate powder.

🔄Procedures:

♻️First preparation of Na-meta-bisulfate
1. Prepare 2% of Na-meta-bisulfate solution
2. Dissolve 2 gram of Na-meta-bisulfate in 100ml D.W
3. This solution, if stored at 3º or 4ºC remains effective for about one week.
4. Stable for 8 hr at room temperature 
♻️Second sickle cell test
1. Place a small drop of capillary blood or vines in the center of a slide.
2. Add an equal drop of the fresh sodium met-bisulfite solution.
3. Mix carefully and cover with a cover slide with petroleum jelly, make sure that no air bubbles form.
4. Place the slide in a wet chamber.
5. Examine under the microscope after 15 minutes using the 40 x objective.
6. The test is negative if the red cells remain round.
7. The test is positive if the cells become sickle-shaped, or banana-shaped. 

↪️ Limitations/ Interfering substance
1. This test should not perform on infant less than six months old
2. Sickling of red blood cells is maximum at 37°c and decrease as the temperature Lowers
3. Sever anemia will cause false negative result
4. Low Hb cause false negative: the use of packed cells will overcome this problem
5. Specimen with 25% Hb F present may cause false negative.
6. Blood from patients with polycythemia, multiple myeloma, dysglobulinemia may cause false positives
7. False-negative results may occur if:
a. Outdated reagents are used.
b. Concentrations of hemoglobin S are low.
c. Patients have moderate or severe anemia.
8. In all cases where abnormalities are indicated or suspected electrophoretic confirmation is recommended 

↪️ Results:
⤴️Negative result The erythrocytes remain round If the test is negative, re-examine the slide after a further 30 minutes, then after 2 hours and after 24 hours.
⤴️Positive result
1. The erythrocytes become sickle-shaped or banana-shaped often with spikes It is important to examine several parts of the preparation, as sickling can occur more quickly in one part than in another.
2. Do not mistake normal erythrocytes lying on their side created cells for sickle cells.

↪️Reporting result:
❇️Positive for sickle cell test.
❇️Negative for sickle cell test.
د. عبدالله احمد
•┈┈┈❈••✦✾✦••❈•┈┈┈•
@LabMed2016

BY الطب المخبري