Electronic platelet counting with capillary blood samples--experiences in a paediatric clinic.

For several reasons, electronic platelet counts have not been generally adopted in paediatric routine laboratories. A method of platelet counting in capillary blood samples using an electronic counter is described. This is based on brief centrifugation of the blood sample after the addition of a diluent containing heparin/dextran and with a density of 1.050. The thrombocytes are uniformly suspended in the supernatant after 5 min of centrifugation at 250 g, so that the counting procedure in the electric unit can follow immediately. This simplified, dependable and reproducible method is also suitable for venous blood, and as a result of several years of successful trial, it can be recommended for routine use, especially in clinics with paediatric patients.