The purpose of this programmes is to assess a laboratory’s ability to calculate the absolute count (cells/μL) of leucocytes in leucodepleted blood products.

The use of leucocyte depleted blood products became standard practice in blood transfusion in response to the possible risk of variant Creutzfeldt-Jakob disease (v-CJD) transmission. However leucodepletion also has many other benefits such as a reduction in febrile transfusion reactions and a reduction in the risk of cytomegalovirus (CMV) transmission. As such the majority of countries now routinely perform leucodepletion on all donated blood products to ensure a minimal number of residual leucocytes remain.

This programme issues six stabilised samples per trial, consisting of three whole blood and three platelet samples. Samples can be analysed by flow cytometry, or by the Nageotte manual method.

Laboratories are requested to report the absolute numbers of leucocytes in each sample expressed in cells per microlitre.

This programme issues samples 6 times per annum for participating centres.

No activities in relation to this EQA exercise were subcontracted.

To register for this programme, please click here.

As a participant in the UK NEQAS LI Low Level Leucocyte Enumeration programme you may also be interested in the complementary Blood Component Monitoring Scheme, assessing red cell (RBC) and platelet (PLT) parameters, run by UK NEQAS Haematology.

For more information, please see our News/Events page.

As a result of an internal review we have taken the decision to adjust the performance monitoring limits for quantitative programmes.

• A result between 2.5 and -2.5 will now be classed as satisfactory

• A result between >2.5 and 3.5 or <-2.5 and -3.5 will be classed as an 'Action’ result, which highlights a potential issue to the laboratory. Two ‘Action’ results in a period of 3 samples would result in classification as a ‘Critical’

• A result above 3.5 or below -3.5 is considered to be a ‘critical’ result requiring immediate investigation by the laboratory