NCI classification of thrombocytopenia in extremely preterm neonates and its association with mortality and morbidity

Background: Thrombocytopenia (TP) is a common finding among preterm neonates and has been associated with mortality and morbidities. Yet, there is no consistent classification for neonatal TP. TP in adults has recently been graded by the National Cancer Institute (NCI) Common Toxicity Criteria and has been shown to predict clinical outcomes. Objective: To use the NCI classification for TP in preterm neonates and elucidate its association with clinical outcomes. Methods: Retrospective chart review was done on neonates born at gestational age (GA) ≤28 weeks and survived for ≥7 days. TP was classified as per NCI guidelines at 7 days and 28 days of age and their association with mortality, major morbidities and hospital length of stay (LOS) were investigated. Results: A total of 286 patients were included in the study with a mean GA of 26.3±1.5 weeks and birth weight of 899±215 g. NCI TP grades at 7 days were significantly (P<0.001) associated with mortality, LOS, intraventricular hemorrhage and Gram negative infections. In addition to these outcomes, necrotizing enterocolitis, Gram positive and fungal infections were also significantly associated with NCI TP grades at 28 days. Conclusions: Classification of TP using the NCI criteria in extreme preterm neonates is clinically applicable. This grading system of platelet counts is significantly associated with mortality, morbidity and LOS in preterm neonates.