Low Level Leucocyte Enumeration (Accredited)

Programme objective: 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.

Clinical/scientific background: 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 most countries now routinely perform leucodepletion on all donated blood products to ensure a minimal number of residual leucocytes remain.

Suitability: Participation in this External Quality Assessment (EQA) programme is open to laboratories employing any Flow Cytometric approach for the enumeration of low level leucocytes in a sample.

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

All EQA programme communications, data entry, and reports will be conducted exclusively in the English language. Participants must ensure proficiency in English to fully engage in the programme.

The programme welcomes participation from diverse sectors including:

Clinical Healthcare Laboratories
Academic and Research Institutions
In Vitro Diagnostics (IVD) Manufacturers
Pharmaceutical companies

Minimum participation level 30, maximum participation level 300.

Sample type/distribution: Three stabilised red blood cell samples and three stabilised platelet samples are issued per trial. This programme issues samples a minimum of 4 and a maximum of 6 times a year.

Trial duration: Trials for this programme are live/open for a minimum of three weeks. Please note trials issued/closing in August or December are extended by one week. An automated email is sent two days prior to the trial closing, to any participant that has not returned results, warning them of the trial closure date.

Subcontracted areas: No activities in relation to this EQA programme are subcontracted.

Updates to the programme for current or upcoming year: Each year we quote a minimum and a maximum number of possible trial distributions that will be issued on our website, subject to sample availability. Historically, we have consistently achieved the maximum number of distributions. In 2025-2026 due to staffing shortage, we are unlikely to hit the maximum number of distributions, as we have in previous years and trials may not be equally distributed throughout the year i.e; bimonthly. We will return to the full trial distribution schedule in 2026-2027. Please accept our apologies for this short-term decrease in our services.

To register for this programme, please click here.