090 - Analytical Performances and Clinical Aims in Laboratory Haematology
Autor(s): P. Cappelletti
Issue: RIMeL - IJLaM, Vol. 4, N. 3-S1, 2008 (MAF Servizi srl ed.)
Page(s): 90-94
The clinical aims of the haematological technology are a safe case finding and an efficient aid for the clinical condition of the patient. The present technological era of haematology developed by the discovery of new methods, the combination of methodologies in one instrument (“technological syncretism”) and the integration of electronic data for suggestive information. On this way, laboratory haematology combined the needs of accuracy and precision of the methods with the hopes of clinical sensitivity and specificity. Attention for counting and measuring is decreasing in last decades because the analytic performances are considered generally excellent, unless the platelets and reticulocytes counts at low concentrations. On the contrary interest for automated cellular recognition is growing because of the possibility of identifying “difficult” or abnormal cells in the blood, with the perspective of an electronic extended differential count (EDC). For this goal it is essential the specificity of flags and/or identification of the cells, beside their sensitivity. The evaluation promoted by Haematology Study Group of SIMeL (GdS-E) in 2002-3 demonstrated Negative Predictive Values (NPV) between 98.3 and 100% for the general flags and a NPV ~ 99% for the combination of general and specific flags. But the Positive Predictive Values and NPVs of single specific flags are lower. Therefore, in 2008 GdS-E re-evaluated the haematological analyzers with the aims of studying the critical points of clinical specificity/sensibility related to functional and prognostic information and the relationship among subjective (physician’ senses and memory) and objective (automated instruments) viewpoints related to the clinical effectiveness of the haematological laboratory information in the so called “non-haematological haematology”. The attention is focused to the issues of the clinical sensitivity at the lower and upper ends of the scale of measuring, i.d. in the critical clinical conditions (example: NRBC); to the issues of the specificity or “quality” of measures and recognitions for linking shape and function (examples: monocytes and granulocytic immaturity); to the issues of technological syncretism and physicians’ skills and culture for effective diagnostic, prognostic, therapeutic information in critical and complex clinical condition (example: sepsis).