Blood sample determination method and blood sample analyzer

Patent metadata

Field	Value
Publication number	US-10215766-B2
Application number	US-201514969698-A
Country	US
Kind code	B2
Filing date	Dec 15, 2015
Priority date	Dec 19, 2014
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

Disclosed is a blood sample determination method including: emitting light to a measurement specimen prepared by mixing a clotting time measuring reagent and a blood sample suspected to be derived from a subject having lupus anticoagulant or a coagulation factor inhibitor, to obtain optical information about an amount of light from the measurement specimen; obtaining at least one parameter regarding derivative of clot waveform, based on the obtained optical information; and determining, based on a value of the obtained parameter, whether the blood sample is suspected to be a sample derived from a subject having lupus anticoagulant or is suspected to be a sample derived from a subject having a coagulation factor inhibitor.

First claim

What is claimed is:

1. A blood sample determination method comprising:
emitting light to a measurement specimen prepared by mixing a clotting time measuring reagent and a blood sample suspected to be derived from a subject having lupus anticoagulant or a coagulation factor inhibitor, to obtain optical information about an amount of light from the measurement specimen;
obtaining at least one parameter regarding derivative of clot waveform, based on the obtained optical information; and
determining, based on a value of the obtained at least one parameter, that the blood sample is suspected to be a sample derived from a subject having lupus anticoagulant, and if not, then determining that the blood sample is suspected to be a sample derived from a subject having a coagulation factor inhibitor.

2. The blood sample determination method of claim 1 , wherein
in the determining, the value of the obtained at least one parameter is compared with a predetermined threshold, and determination on the blood sample is made based on a result of the comparison.

3. The blood sample determination method of claim 1 , wherein
the optical information is an amount of scattered light, transmittance, or absorbance which has been measured continuously or intermittently, and the clot waveform is a waveform representing temporal change in the amount of scattered light, the transmittance, or the absorbance.

4. The blood sample determination method of claim 1 , wherein
the at least one parameter regarding derivative of clot waveform is at least one selected from the group consisting of maximum coagulation velocity (|min 1|), maximum coagulation acceleration (|min 2|) and maximum coagulation deceleration (max 2).

5. The blood sample determination method of claim 4 , wherein
in the determining,
the value of |min 1| is compared with a first threshold in a case where |min 1| has been obtained, the value of |min 2| is compared with a second threshold in a case where |min 2| has been obtained, and the value of max 2 is compared with a third threshold in a case where max 2 has been obtained,
when at least one of the values that have been obtained among |min 1|, |min 2|, and max 2 is greater than or equal to a predetermined threshold corresponding to that value, it is determined that the blood sample is suspected to be a sample derived from a subject having lupus anticoagulant, and
when all the values that have been obtained among |min 1|, |min 2|, and max 2 are smaller than predetermined thresholds corresponding to those values, it is determined that the blood sample is suspected to be a sample derived from a subject having a coagulation factor inhibitor.

6. The blood sample determination method of claim 4 , wherein
|min 1| is obtained in the obtaining of the at least one parameter, and
in the determining, the value of |min 1| is compared with a first threshold, and when the value of |min 1| is greater than or equal to the first threshold, it is determined that the blood sample is suspected to be a sample derived from a subject having a lupus anticoagulant, and when the value of |min 1| is smaller than the first threshold, it is determined that the blood sample is suspected to be a sample derived from a subject having a coagulation factor inhibitor.

7. The blood sample determination method of claim 4 , wherein
|min 1|, |min 2<, and max 2 are obtained in the obtaining of the at least one parameter,
in the determining, the value of |min 1| is compared with a first threshold, the value of |min 2| is compared with a second threshold, and the value of max 2 is compared with a third threshold,
when at least one value of |min 1|, |min 2|, and max 2 is greater than or equal to the threshold corresponding to that value, it is determined that the blood sample is suspected to be a sample derived from a subject having lupus anticoagulant, and
when the value of |min 1| is smaller than the first threshold, the value of |min 2| is smaller than the second threshold, and the value of max 2 is smaller than the third threshold, it is determined that the blood sample is suspected to be a sample derived from a subject having a coagulation factor inhibitor.

8. The blood sample determination method of claim 1 , wherein
the clotting time measuring reagent is a reagent for measuring at least one selected from the group consisting of prothrombin time, activated partial thromboplastin time, dilute prothrombin time, dilute activated partial thromboplastin time, kaolin clotting time, dilute Russell's Viper Venom time, thrombin time, and dilute thrombin time.

9. The blood sample determination method of claim 1 , wherein
the blood sample is whole blood or plasma.

10. A blood sample determination method comprising:
emitting light to a measurement specimen prepared by mixing a blood sample and a clotting time measuring reagent, to obtain optical information about an amount of light from the measurement specimen;
obtaining a clotting time and obtaining at least one parameter regarding derivative of clot waveform, based on the obtained optical information; and
with respect to a blood sample for which prolongation of the clotting time is observed, determining, based on a value of the obtained at least one parameter, that the blood sample is suspected to be a sample derived from a subject having lupus anticoagulant, and if not, then determining that the blood sample is suspected to be a sample derived from a subject having a coagulation factor inhibitor.

Assignees

• Public Univ Corporation Nara Medical Univ
• Sysmex Corp

Inventors

• Shima Midori
• Nogami Keiji
• Tabuchi Yuka
• Kurono Hiroshi

Classifications

• G01N21/49

  within a body or fluid · CPC title

• G01N21/75

  Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated (systems in which material is burnt in a flame or plasma G01N21/72, G01N21/73) · CPC title

• G01N33/86 Primary

  involving blood coagulating time {or factors, or their receptors} · CPC title

• G01N21/82

  producing a precipitate or turbidity · CPC title

• G01N33/4905

  Determining clotting time of blood (by chemical methods G01N33/86, C12Q1/56) · CPC title