How accurate is manual platelet count?
The mean platelets count estimated by the manual method was 225.2 ± 95.4 × 109/L, while that estimated by the automated method was 245.7 ± 109.8 × 109/L, with no significant statistical difference between both means (p>0.05).
How often are platelet counts wrong?
Diagnosis and discussion Pseudothrombocytopenia is defined as a falsely low platelet count, with an estimated frequency of between 1 in 1,000 and 1 in 10,000 blood specimens collected in ethylenediaminetetra-acetic acid (EDTA)-containing tubes.
Can a platelet count be wrong?
The platelet count can be biased in a substantial number of cases. Platelet count can be reduced and remain within normal limits or may show false thrombocytopenia or artefactually accentuate true thrombocytopenia.
Why would a manual platelet count be ordered by a physician?
A platelet count is often ordered as a part of a complete blood count (CBC) when you have a routine health exam. It may be ordered when you have signs and symptoms associated with low platelets or a bleeding disorder, such as: Unexplained or easy bruising. Prolonged bleeding from a small cut or wound.
How is manual platelet count done?
Manual Platelet Counts The determination is done by placing a small volume of diluted whole blood that was treated with a red cell lysing reagent, such as ammonium oxalate, in a counting chamber (hemocytometer), and counting platelets using phase contrast light microscopy.
What can cause a false platelet count?
Platelet Count
| Condition | Inheritance | Abnormality |
|---|---|---|
| May-Hegglin | Autosomal Dominant | Severe thrombocytopenia |
| Wiskott-Aldrich | Sex-linked | Severe thrombocytopenia with small platelets |
| Congenital thrombopoietin deficiency | ? Autorecessive | Severe thrombocytopenia |
| Thrombocytopenia with absent radius | Autorecessive | Moderate thrombocytopenia |
How do you manually count platelets?
An estimated platelet count can be done quickly with a blood smear evaluated at 100× magnification. At this magnification, the platelet count/µL of blood can be approximated by multiplying the number of platelets seen in one microscope field by 15,000.
Do you need to fast for a CBC with differential platelet?
You don’t need any special preparations for a complete blood count. If your health care provider has also ordered other blood tests, you may need to fast (not eat or drink) for several hours before the test.
What does a differential blood count tell you?
A differential blood count gives the relative percentage of each type of white blood cell and also helps to reveal abnormal white blood cell populations (eg, blasts, immature granulocytes, and circulating lymphoma cells in the peripheral blood).
What is the second most accurate method to do in platelet counting?
A second method for manual platelet counting involves counting platelets in an area containing 1,000 red cells, with the platelet count (× 109/L) being the number of platelets counted multiplied by the red blood cell count.