Pseudo-thrombocytopenia dependent on EDTA-K2 and sodium citrate at the same time, have you seen it?

For clinical laboratory workers, thrombocytopenia is a common condition for us.
There are many reasons for thrombocytopenia, including primary thrombocytopenia and secondary thrombocytopenia.
For our laboratory workers, it should be more Attention is to rule out platelet pseudo-reduction to avoid clinical misdiagnosis
.

For clinical laboratory workers, thrombocytopenia is a common condition for us.
There are many reasons for thrombocytopenia, including primary thrombocytopenia and secondary thrombocytopenia.
For our laboratory workers, it should be more Attention is to rule out platelet pseudo-reduction to avoid clinical misdiagnosis
.

So let's explore the reasons for thrombocytopenia in the following case

.

So let's explore the reasons for thrombocytopenia in the following case

case after

One morning in December 2021, while processing specimens as usual, a patient's test results caught my attention:

One morning in December 2021, while processing specimens as usual, a patient's test results caught my attention:

Patient: female, 37 years old, blood routine results are as shown: WBC 4.

81×10 ⁹ /L, RBC 4.

Patient: female, 37 years old, blood routine results are as shown: WBC 4.

Initially, the main abnormality of this report is thrombocytopenia, other indicators are basically normal, and platelet-related parameters MPV, PDW, P-LCR are all high, so consider whether it is large platelets or EDTA-dependent thrombocytopenia?

Initially, the main abnormality of this report is thrombocytopenia, other indicators are basically normal, and platelet-related parameters MPV, PDW, P-LCR are all high, so consider whether it is large platelets or EDTA-dependent thrombocytopenia?

Due to the triggering of the re-examination rules formulated by our department, after the thrombocytopenia caused by unqualified factors such as specimen agglutination was initially excluded, we carried out the re-examination of the specimen by pushing the specimen, and the platelets were found to be clustered together under the microscope.

One sample was due to EDTA-dependent pseudothrombocytopenia (EDTA-dependent pseudo thrombocytopenia, EDTA-PTCP)

Due to the triggering of the re-examination rules formulated by our department, after the thrombocytopenia caused by unqualified factors such as specimen agglutination was initially excluded, we carried out the re-examination of the specimen by pushing the specimen, and the platelets were found to be clustered together under the microscope.

×100 times St.

Regis staining

×100 times St.

For EDTA-PTCP patients, our current main treatment method is to re-collect a tube of sodium citrate anticoagulation for testing, and multiply the platelet test result by 1.

So we asked the patient to re-collect a tube of sodium citrate anticoagulation.

The platelet results are not consistent with the expected results, and the platelets are still low.

×100 times St.

Regis staining

×100 times St.

This result seems a bit unexpected to us.
What happened to this patient? Is this a pseudo-thrombocytopenia caused by simultaneous dependence on EDTA and sodium citrate?

After that, we used sodium citrate anticoagulation to add PLT-F channel for detection.
The result of this patient's platelet detection was PLT 162×10 ⁹ /L, which was basically consistent with our manual counting results
.
Therefore, the final result of the PLT (178×109/L) was multiplied by 1.
1 as the result of the platelet F channel and reported
.

After that, we used sodium citrate anticoagulation to add PLT-F channel for detection.
The result of this patient's platelet detection was PLT 162×10 ⁹ /L, which was basically consistent with our manual counting results
.
Therefore, the final result of the PLT (178×109/L) was multiplied by 1.
1 as the result of the platelet F channel and reported
.
⁹

case analysis

case analysis

The currently generally recognized mechanism of EDTA-PTCP is mainly immune factors.
Under the action of EDTA, GPlIb/IIIa stimulates the expression of CD62P, CD63 and thrombospondin, which activates the expression of activating antigens and triggers the activity of tyrosine kinases, resulting in the occurrence of platelets in vitro.
gather
.

The currently generally recognized mechanism of EDTA-PTCP is mainly immune factors.
Under the action of EDTA, GPlIb/IIIa stimulates the expression of CD62P, CD63 and thrombospondin, which activates the expression of activating antigens and triggers the activity of tyrosine kinases, resulting in the occurrence of platelets in vitro.
gather
.
immunity

When the laboratory encounters a false decrease in PLT, it will generally replace the sodium citrate anticoagulant and take it again, or directly remove the peripheral blood for testing.
Most EDTA-dependent false thrombocytopenia can be corrected, but some cannot be corrected.
The case is an uncorrectable situation.
The pseudo-thrombocytopenia caused by the simultaneous dependence of two anticoagulants, EDTA and sodium citrate, is still unclear
.

When the laboratory encounters a false decrease in PLT, it will generally replace the sodium citrate anticoagulant and take it again, or directly remove the peripheral blood for testing.
Most EDTA-dependent false thrombocytopenia can be corrected, but some cannot be corrected.
The case is an uncorrectable situation.
The pseudo-thrombocytopenia caused by the simultaneous dependence of two anticoagulants, EDTA and sodium citrate, is still unclear
.

In this case, the platelet F channel is used for detection, and an accurate count of platelets can be obtained, which is related to the detection principle of the F channel.
The PLT-F channel adopts the principle of flow detection, and uses a special fluorescent dye to specifically detect the nucleic acid in platelets.
Combined, different forward scattered light and lateral fluorescence intensities are formed after staining, and accurate platelet counts can be accurately determined by detecting scattered light and fluorescence
.
PLT-F can rule out the influence of large platelets, microplatelets, cell debris and small red blood cells on platelet count
.

In this case, the platelet F channel is used for detection, and an accurate count of platelets can be obtained, which is related to the detection principle of the F channel.
The PLT-F channel adopts the principle of flow detection, and uses a special fluorescent dye to specifically detect the nucleic acid in platelets.
Combined, different forward scattered light and lateral fluorescence intensities are formed after staining, and accurate platelet counts can be accurately determined by detecting scattered light and fluorescence
.
PLT-F can rule out the influence of large platelets, microplatelets, cell debris and small red blood cells on platelet count
.

In addition, an article published in the laboratory medicine official account mentioned that attention should be paid to distinguish between the false reduction of platelets caused by EDTA dependence and the short-term aggregation of platelets after they are isolated from the body.
This is also for thrombocytopenia.
We should pay special attention to the difference in our work.
The main point of the EDTA-PTCP microscopy is that a large piece of PLT in the end of the film is aggregated together (the number of aggregated platelets is large)
.
The short-term aggregation of platelets in vitro is that a small pile of PLT in the tail of the body can be seen on microscopy (the number of aggregated platelets is not as much as EDTA-dependent).

In addition, an article published in the laboratory medicine official account mentioned that attention should be paid to distinguish between the false reduction of platelets caused by EDTA dependence and the short-term aggregation of platelets after they are isolated from the body.
This is also for thrombocytopenia.
We should pay special attention to the difference in our work.
The main point of the EDTA-PTCP microscopy is that a large piece of PLT in the end of the film is aggregated together (the number of aggregated platelets is large)
.
The short-term aggregation of platelets in vitro is that a small pile of PLT in the tail of the body can be seen on microscopy (the number of aggregated platelets is not as much as EDTA-dependent).

In conclusion, for anticoagulant-dependent pseudo-thrombocytopenia, EDTA-PTCP is more common in clinical practice.
Although it is rare to be dependent on two anticoagulants at the same time, we should also pay attention to it in clinical testing
.
Provide accurate and reliable results for clinical practice, so as to avoid misdiagnosis and mistreatment caused by thrombocytopenia
.

In conclusion, for anticoagulant-dependent pseudo-thrombocytopenia, EDTA-PTCP is more common in clinical practice.
Although it is rare to be dependent on two anticoagulants at the same time, we should also pay attention to it in clinical testing
.
Provide accurate and reliable results for clinical practice, so as to avoid misdiagnosis and mistreatment caused by thrombocytopenia
.

references

references

[1] Bai Zhiyao, Sun Jiqin, etc.
EDTA-K2 and sodium citrate anticoagulant-dependent pseudothrombocytopenia: analysis of two cases [J].
"Journal of Practical Laboratory Physicians", 2015, 7(4): 256-259.

[1] Bai Zhiyao, Sun Jiqin, etc.
EDTA-K2 and sodium citrate anticoagulant-dependent pseudothrombocytopenia: analysis of two cases [J].
"Journal of Practical Laboratory Physicians", 2015, 7(4): 256-259.

[2] Xu Yisheng.
"Attention to the window of the inspection colleagues, the result is not the sooner the better! 》.
Public Number: Laboratory Medicine 2021-12-30

[2] Xu Yisheng.
"Attention to the window of the inspection colleagues, the result is not the sooner the better! 》.
Public Number: Laboratory Medicine 2021-12-30 Leave a message here