10020457
10020363
10020468
10020470
Erba Lachema s.r.o., Karásek 2219/1d, 621 00 Brno, CZ
e-mail: diagnostics@erbamannheim.com, www.erbamannheim.com
N/148/17/D/INT
Date of Revision: 17 .8. 2017
QUALITY SYSTEM CERTIFIED
ISO 9001 ISO 13485
Erba Protime LS
Prothrombin Time
Cat. No.
Pack name
Packaging (Content)
EHL00023
Erba Protime LS 4
2 x 2 ml
EHL00024
Erba Protime LS 10
2 x 5 ml
EHL00046
Erba Protime LS 50
10 x 5 ml
EHL00047
Erba Protime LS 100
10 x 10 ml
IVD
INTENDED USE
Erba Protime LS is a liquid ready to use rabbit brain thromboplastin intended for the
determination of the prothrombin time (PT).
CLINICAL SIGNIFICANCE
Erba Protime LS thromboplastin is a rabbit brain extract, which contains tissue factor,
lipids and calcium ions. The first standardized one-stage prothrombin time test was
developed by Dr. Armand Quick in 1935. It has now become the basic coagulation
screening test for the diagnosis of congential and acquired deficiencies of clotting factors
from the extrinsic pathway (factors II, V, VII and X). It is also used for the induction and
monitoring of oral anticoagulant therapy
and can be used to assess the protein synthesis
capability of the liver in chronic or acute hepatic disorders.
Therefore, the PT by Erba Protime LS is optimally used for presurgical screening and
monitoring for oral anticoagulant therapy (OAT) also. Erba Protime LS reagent with the
corresponding deficient plasmas is also suitable for determination of activity of extrinsic
coagulation pathway (factor II, V, VII and X).
PRINCIPLE
The one-stage PT measures the clotting time of plasma after adding a source of
tissue factor (thromboplastin) and calcium. The recalcification of plasma in the
presence of tissue factor generates activated factor Xa. Factor Xa in turn activates
prothrombin to thrombin, which converts fibrinogen to an insoluble fibrin clot.
The time of this clotting process is measurable manually or with optical or mechanical
coagulation analysers.
COMPOSITION
Erba Protime LS
is a tissue thromboplastin from rabbit brain, which contains calcium
ions and sodium azide (<0,01%) as preservative
WARNINGS AND PRECAUTIONS
For in vitro diagnostic use only. These reagents are to be used by certified medical
laboratory personnel only.
Do not ingest.
Wear gloves when handling all kit components.
Only use clean or single use laboratory equipment to avoid contaminations.
The eventual rest of reagents should be disposed of in accordance with the internal
regulations and in compliance with local and national regulations relating to the
safe handling of waste.
WARNING - POTENTIAL BIOHAZARDOUS MATERIAL
Some reagents provided in these kits contain materials of human and/or animal
origin.
Whenever human plasma is required for the preparation of these reagents, the
plasmas are tested for the antibodies to HIV 1. HIV 2 and HCV, and for hepatitis B
surface antigen. and results are found to be negative. However, no test method can
offer complete assurance that infectious agents are absent. Therefore, users of
reagents of these types must exercise extreme care in full compliance with regulatory
safety precautions in the manipulation of these biological materials as if they were
infectious.
WORKING REAGENT
Erba Protime LS
is ready to use.
The contents of the vial should be mixed well before use (5 minutes).
Using of stirring bar is necessary!
STABILITY AND STORAGE
The unopened reagents are stable till the expiry date stated on the bottle and kit label when
stored at 2–8°C.
Opened vials are stable:
-
2 months at 2-8°C
-
5 days at 15°C
-
6 hours at 37°C
Do not freeze.
SAMPLE COLLECTION AND PREPARATION
Plastic or siliconised glass should be used throughout.
Blood (9 parts) should be collected into 3.2% or 3.8% sodium
citrate anticoagulant (1 part). Separate plasma after centrifugation at 1500 x g for 15
minutes. Plasma should be kept at 18-24°C. Testing should be completed within 4 hours of
sample collection, or plasma can be stored frozen at -20°C for 2 weeks or -70°C for 6
months. Thaw quickly at 37°C prior to testing. Do not keep at 37°C for more than 5 minutes.
PROCEDURE
Erba Protime LS is a one-stage PT test which can be used with semi-automated coagulation
analysers according to the protocol detailed below.
Manual Method
Mix sufficient Erba Protime LS reagent to complete the anticipated testing for the day and
incubate reagent at 37°C no more than 4 hours
Add 50 µl of the patient plasma or control plasma into a reaction tube and incubate at
37°C for 2 minutes.
Add 100 µl of freshly mixed reagent and start simultaneously a timer.
Note the time for clot formation to the nearest 0.1 seconds
Automated Method
Refer to the instrument’s operator’s manual.
INTERPRETATION OF RESULTS
Erba Protime LS test results can be reported in the following units, lot specific sheet in the
box will help in the calculation:
1.
Seconds
, which means the observed clotting time.
2.
Percentage
, which means the proportional part of the normal PT activity, which is
calculable from the calibration curve. Method dependent master curve in the issued sheet
can be used for the calculation.
3.
International Normalized Ratio (INR),
calculated as
INR=(PT/MNPT)
ISI
. Where PT
means the clotting time of the sample, MNPT means Mean Normal Prothrombin Time and
ISI means International Sensitivity Index. The ISI method dependent values in the lot specific
values sheet can be used for the calculation.
- The INR is the only officially recognized dimension of the result at vitamin K antagonists
treated patients. The normal range expressed in INR is 0,8-1,2.
- Every laboratory should determine its own MNPT value and reference range. MNPT
value in the issued sheet is only for information, because it depends on the measuring
circumstances and population.
- Accurate and general conversion of percentage into INR (or back) is not possible!
REFERENCES VALUES
Reference values can vary between laboratories depending on the techniques and systems
in use. For this reason each laboratory should establish its own reference ranges. This is
particularly important for local ISI calibration. Using an optical coagulation analyzer, normal
values ranging from 11.5-14.6 seconds; 0.93-1.16 INR; 79.1-112.8 %PT are typical.
QUALITY CONTROL
Each laboratory should establish a quality control program.
To ensure adequate quality, control plasmas are recommended. It is suggested to use
two levels of control, one close to the normal patient values (Erba Control N, Cat. No.:
EHL00014 or Erba Control N Plus, Cat. No.: EHL00016) and the second representative
the pathologic values (Erba Control P, Cat. No.: EHL00015 or Erba Control P Plus, Cat.
No.: EHL00017).
LIMITATIONS
Erba Protime LS is insensitive to the following substances:
Heparin: up to 2 IU/mL
Bilirubin: up to 0.5 g/l
Heamoglobin: up to 10 g/l
Triglycerides: up to 3.75 g/l
PERFORMANCES
These performances have been obtained using ECL coagulation analyzer. Results may vary
if a different instrument or manual procedure is used.
Precision
Intra-assay precision (N = 20)
Inter-assay precision (N = 10)
Mean (s)
12.4
25.6
12.7
24.8
CV (%)
0.49
1.46
2.18
1.95
REFERENCES
1. Quick AJ (1935) A Study of the Coagulation Defect in Hemophilia and Jaundice,
Am. J.
Med. Sci,
190:
501.
2. Biggs R (1976) Human Blood Coagulation, Haemostasis and Thrombosis, 2nd Edition,
Blackwell Scientific Publications, London.
3. Hirsh J, Poller L, Deykin D, Levine J, Dalen JE (1989) Optimal Therapeutic Range for Oral
Anticoagulants,
Chest,
95:
5S-11S.
4. Poller L (1986) Laboratory Control of Anticoagulant Therapy,
Sem. Thromb. Haemostasis,
12:
13-19.
5. World Health Organisation (1984) Expert Committee on Biological Standards,
Technical
Series,
700:
19.
6. Clinical and Laboratory Standards Institute (2008) Collection, Transport and Processing of
Blood Specimens for Testing Plasma-Based Coagulation Assays and Molecular
Haemostasis Assays: Approved Guideline, 5th edn. CLSI: H21-A5.
7. Poller L., Triplett DA, Hirsh J, Carroll J, Clarke K (1995) The value of plasma calibrants in
correcting coagulometer effects on International Normalised Ratios (INR): An international
multicentre study,
Amer. J. Clin. Pathol,
103:
358-365.
8. Poller L, Triplett DA, Hirsh J, Carroll J, Clarke K (1995) A comparison of lyophilised
artificially depleted plasmas and lyophilised plasmas from warfarin treated patients in
correcting for coagulometer effects on International
Normalised Ratios,
Amer. J. Clin. Pathol,
103:
366-371.
9. Keeling D (2011) Guidelines on Oral Anticoagulation with warfarin: Forth Edition,
British
Journal of Haematology,
154(3):
311-324.
USED SYMBOLS
REF
Catalogue No
CE Mark - Device comply with the Directive 98/79/EC
LOT
Batch Code
IVD
In Vitro Diagnostics
Expiry Date
(Last day of the month)
Consult
Manufactured by
Storage temperature
Instruction for Use
Erba Protime LS
Product Name
CONT
Content
