Thrombocytopenia in neonates with polycythemia: incidence, risk factors and clinical outcome

Background: Polycythemia occurs in 1 to 5% of neonates and is associated with complications, including an increased risk of thrombocytopenia.

Objective: To evaluate incidence, risk factors, management and outcome of thrombocytopenia in neonates with polycythemia.

Study design: All neonates with polycythemia admitted to our neonatal intensive care unit between 2006 and 2013 were included in this retrospective study. We evaluated the incidence of thrombocytopenia (platelet count <150 × 10(9)/l) and severe thrombocytopenia (platelet count <50 × 10(9)/l) and the correlation between platelet counts and hematocrit values.

Results: The incidence of thrombocytopenia and severe thrombocytopenia was 51 (71/140) and 9% (13/140), respectively. Platelet count was negatively correlated with hematocrit (spearman correlation coefficient -0.233, p = 0.007). After multiple regression analysis, we found an independent association between thrombocytopenia and being small for gestational age (OR: 10.0; 95%; CI: 1.2-81.7; p = 0.031).

Conclusion: Thrombocytopenia occurs in 51% of neonates with polycythemia and is independently associated with growth restriction. Increased hematocrit is associated with decreased platelet count.