[Secondary surfactant deficiencies in extremely low birth weight premature infants].

Primary deficiency of surfactant is responsible for the respiratory distress syndrome and concerns premature neonates born before 33 weeks of gestation. However, newborns may develop respiratory disorders related to a secondary deficiency or dysfunction of surfactant. We report the course of three extremely low birth weight premature infants who experienced clinical respiratory decompensation at two weeks and showed a marked improvement after exogenous natural surfactant administration.