Massive RBC fragmentation masks severe thrombocytopenia in both impedance and optical platelet count measurements – a case report of a neonate on ECMO support

Extracorporeal membranous oxygenation (ECMO) is a life-saving treatment for pae-diatric patients with cardiac or respiratory failure of diverse aetiology. ECMO sup-port is implemented only when all other available medications and procedures fail to treat the underlying cause of organ fail-ure. The reason for caution is a high risk of complications, including intravascular haemolysis, bleeding or clot formation, inflammation and sepsis. Platelet count is closely monitored in assessment of bleed-ing risk associated with ECMO support. Platelets are counted as a parameter of the complete blood count and can be measured using impedance or optical technology. We report a case of severe red blood cell (RBC) fragmentation in a neonate on ECMO in whom erroneously normal platelet counts were obtained by all available automated methods for platelet count in an emergen-cy laboratory. Based on those observations we have implemented an additional proce-dure for recognising interferences of frag-mented and microcytic RBCs that cause spuriously normal platelet counts.

platelet count, ECMO, frag-mented RBC, neonates, analytical interfer-ence

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