Predictors of early mortality in Down syndrome-associated transient abnormal myelopoiesis

Abstract

Objective: To identify clinical and laboratory factors associated with early mortality in neonates and infants with Down syndrome-associated transient abnormal myelopoiesis. Bibliographic review: Most cases resolve spontaneously, but some patients develop hepatic and cardiopulmonary involvement and organ failure. Prematurity, low birth weight, hyperleukocytosis, ascites, hydrops, and bleeding manifestations have been associated with adverse outcomes in observational cohorts. Rising direct bilirubin, hypoalbuminemia, and coagulopathy warrant serial assessment because hepatic deterioration may continue despite decreasing blast counts. Mechanical ventilation, vasoactive support, and inhaled nitric oxide often reflect established severe disease rather than equivalent baseline predictors. Cytokines, chemokines, and hyaluronic acid are promising biomarkers but remain insufficiently validated. Low-dose cytarabine may benefit severely symptomatic patients, although prevention of later myeloid leukemia has not been demonstrated. Final considerations: Early mortality has a multifactorial basis. Integrating clinical findings and laboratory trends over time may improve recognition of higher-risk infants, while interpretation is constrained by small heterogeneous studies and limited external validation.