In haematopoietic stem cell transplantations the use of CD34+ stem cell enumeration is an essential part of the treatment process, allowing for monitoring of donor mobilisation pre harvest and to ensure sufficient cells are collected to ensure engraftment will occur.
This programme is currently the largest world-wide for CD34+ haematopoietic progenitor cell (hpc) enumeration. The programme uses stabilised peripheral blood obtained from consenting patients following stem cell mobilisation and is suitable for use with whole blood lysis techniques and sequential gating strategies.
Laboratories are requested to report both percentage and absolute values (in cells per microlitre), although performance is only monitored using the absolute values. Two samples are issued per trial and this programme issues trials a minimum of 4 times per annum and a maximum of 6.
No activities in relation to this EQA programme are subcontracted.
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