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I have read some old papers indicating that the 1 hour reading time of the ESR can be greatly reduced by fixing the tube at an angle of 60 or 45 degrees instead of upright. Does this give accurate results?

No, the ESR tube (DispetteTM) must always be perfectly vertical as measured by a spirit bubble or plumb line. The papers in favour of the idea written in the mid 1930’s and early 1940’s were shown to be faulty by several workers and finally discredited in 1967 (Lemtis and Schoetensack). The ICSH continues to recommend that the tube “should be held vertical (confirmed by a plumb line or equally effective device)”

Can I use EDTA anticoagulated blood to perform the ESR test?

Yes, but if you are performing the Westergren method test as do most people today, you still need to make the one in five dilution (i.e. four parts blood added to one part diluent) that was used with the original technique because only liquid citrate was available at that time as an anticoagulant. The diluent you use can be normal saline or trisodium citrate at a concentration of between 0.10 to 0.136 mol/litre. – see ICSH. recommendations, Journal of Clinical Pathology, 1993; 46: 198 – 203.

When filling the Dispette 2 system, if the blood reaches the zero mark at the top before the other end of the Dispette gets to the bottom of the filling reservoir should I stop pushing and just set up the test in the stand as it is?

No, otherwise the red cells will fall into the space between the bottom of the Dispette and the filling reservior and hence give inaccurate results. The overflow chamber above the zero mark on the Dispette is designed to take the excess blood that will result from pushing right to the bottom.

Can the micro method give the same accuracy as the full Westergren method?

No, although some workers have shown good correlation between the two methods in ESRs giving normal to slightly raised values ( Barrett BA, Hill PI. J Clin Path, 1980; 33: 1118 – 1120). But the higher the ESR the greater is likely to be the variation between the results given by the two methods. Never-the-less this means that the Micro-Dispette can be a very useful screening method or an indicator of normal or raised ESR values where it is difficult to obtain a larger volume of blood sample.

Do Guest ESR systems conform to NCCLS Standards?

Yes, those pipettes marked ‘Westergren’ on the tube (i.e DispetteTM, Dispette 2TM, and VacupetteTM) are designed to meet the specifications set by the International Congress for Standardisation in Haematology, published in 1993. The NCCLS standards were revised to conform to the ICSH Standards later that same year The citrated blood collection bottles and five-place ESR stand are also designed to meet ICSH recommendations.

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