Neonatal Polycythemia and Hyperviscosity

The authors examine the diagnostic and management problems posed by infants with neonatal polycythemia and/or hyperviscosity, with special emphasis on the recently recognized complications of polycythemia in an attempt to address the question of which infants with polycythemia-hyperviscosity are likely to have neonatal symptoms and which infants, symptomatic or asymptomatic, will have sequelae.