External Quality Control in Immunohaematology in the Czech Republic,1992-2000

Overview

External control is an important part for ensuring quality of immunohaematological examinations onwhich depends the safety of transfusion substitution treatment. In the Czech Republic external controlwas introduced in 1992. During the first two years control was ensured entirely by the Referencelaboratory for immunohaematology at the Institute of Haematology and Blood Transfusion (ÚHKT), insubsequent years in the organizational and administrative part SEKK participated. Within the framework of external control the following examinations are followed up: assessment of AB0, assessment ofRhD, assessment of other erythrocyte antigens, direct antiglobulin test, antibody screening andantibody identification. The number of participating laboratories increased from the initial 38 to morethan 200. The results are evaluated according to different parameters and presented in figures andtables. In the basic examinations, AB0 and RhD assessment, there are long-term satisfactory results innormally expressed antigens, problems arise only in weak and variant antigens. In another basicexamination, screening of alloantibodies, an improving trend is observed. Difficulties persist as regardsdetection of weaker antibodies which react only in the indirect antiglobulin test, in particular whenthe classical tube test technique is used.

Key words:
external control, assessment of AB0 RhD, assessment of other red cell antigens, directantiglobulin test, antibody screening, alloantibody identification