Predictive Factors for Severe Thrombocytopenia and Classification of Causes of Thrombocytopenia in Premature Infants

ABSTRACT

PURPOSE: This study investigated predictive factors for severe neonatal thrombocytopenia, which greatly increases the need for intensive care and is associated with a high mortality rate in premature infants. Factors adopted for prompt identification of at-risk newborns include blood test results and birth history. This study analyzed the relationship between the presence of severe neonatal thrombocytopenia and the mortality rate. The causes of thrombocytopenia in premature infants were also examined. METHODS: This retrospective study evaluated 625 premature infants admitted to the neonatal intensive care unit (NICU) at Chung-Ang University Medical Center. The neonates were classified into 3 groups according to the severity of thrombocytopenia: mild (100×10⁹/L≤platelet < 150×10⁹/L), moderate (50×10⁹/L≤platelet < 100×10⁹/L), or severe (platelet < 50×10⁹/L). Analysis of blood samples obtained at the onset of thrombocytopenia included platelet count, white blood cell (WBC) count, hemoglobin level, hematocrit level, absolute neutrophil count, and high-sensitivity C-reactive protein level. RESULTS: Of the 625 premature infants admitted to our NICU, 214 were detected with thrombocytopenia. The mortality rate in thrombocytopenic neonates was 18.2% (39/214), whereas a mortality rate of only 1.0% was observed in non-thrombocytopenic neonates. The major causes of thrombocytopenia were perinatal insufficiency and sepsis in premature infants. Severe thrombocytopenia was noted more frequently in premature infants with higher WBC counts and in those with a younger gestational age. CONCLUSION: Platelet count, WBC count, and gestational age are reliable predictors for severe neonatal thrombocytopenia. The major causes of thrombocytopenia were perinatal insufficiency and sepsis in premature infants.