The strategy of laboratory diagnostics and differential diagnostics of thrombocytopenia

Czech version

Authors: M. Kušnierová; P. Kessler
Authors‘ workplace: Oddělení hematologie a transfuziologie Nemocnice Pelhřimov, p. o., přednosta prim. MU Dr. Petr Kessler
Published in: Vnitř Lék 2010; 56(Supplementum 1): 104-108
Category: 16th Parizek's Days, Ostrava-Poruba, March 25th –26th 2010

Overview

Thrombocytopenia is a pathological state characterized by decreased platelet count under the lower limit of the physiological range, i.e. 150 × 10⁹ per liter. This disorder can be associated with clinical manifestation of the hemorrhagic diathesis. The risk of bleeding is closely associated with the depth of platelets count decrease. Spontaneous bleeding (in absence of any other coagulation disorder) usually occurs when the platelet count decreases below 20 × 10⁹ per liter. The first step, which should be done, when a newly diagnosed thrombocytopenia occurs, is a thorough review of a blood smear. Firstly, it is necessary to exclude the pseudothrombocytopenia, caused by an abnormal in vitro aggregation of thrombocytes, or (much less frequently) by platelet satelitism. It is also necessary to evaluate the red and white cells, especially to focus on the presence of schistocytes or blasts. Thereafter it is recommended to follow a standard diagnostic algorithm, which should be available in every hematological laboratory.

Key words:
laboratory diagnostics – thrombocytopenia – pseudothrombocytopenia

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