Objectives: To determine the association between the first thyroxine blood concentration and necrotizing enterocolitis (NEC) among preterm infants.
Study design: The study group included a cohort of 34 preterm infants with NEC developed at least 48 h after thyroid function screening was obtained. The control group was consisted of 102 preterm infants (3 infants for each infant with NEC, born at the same gestational age) without NEC. Clinical data and first filter paper of total blood thyroxine concentration taken in the first 2 weeks of life were recorded retrospectively and compared between the study and control groups.
Results: Mean filter paper total thyroxine concentration was slightly lower in the study group compared to the control group (86.2 nmol/L and 97.8 nmol/L, respectively) but did not reach statistical significance (p=0.14). Nine infants (26.5%) in the study group were small for gestational age (SGA) in comparison to 11 infants (10.8%) in the control group (p=0.07).
Conclusions: It seems that the first thyroxin serum concentration is not a significant predisposing risk factor for NEC in preterm infants.