Do the Infant Respiratory Distress Syndrome and Presumed Sepsis affect Thyroid Function in Preterm Newborns within the First 10 Days of Life?

Abstract

Janeiro, Brazil, who required NICU care for more than 48 hours and remained hospitalized for 10 days or more between May 2013 and April 2016. An intentional non probability sampling strategy was used, whereby infants were enrolled systematically and consecutively.We excluded all patients with congenital malformations and those whose guardians did not provide written informed consent for participation.Gestational age (in weeks), birth weight (in grams), and 1-minute and 5-minute Apgar scores were obtained from the neonates' hospital records.The preterm neonates enrolled in the study were divided into four groups: 1. No IRDS or sepsis. These formed the Control Group (CG); 2. Those diagnosed with IRDS (IG); 3. Those with presumed sepsis (SG); and 4. Those with both IRDS and Presumed Sepsis (ISG).Gestational age was assessed by the new Ballard method. When this was not possible, it was based on the date of last menstrual period or on the findings of the most recent obstetric ultrasound, as recorded in the mother's medical record.For diagnosis of IRDS, we considered chest X-ray findings and the individual and clinical evaluation of the patient regarding the need for supplemental oxygen and the presence of respiratory distress.For diagnosis of presumed sepsis, we used the hematological scoring system of Rodwell [6]. In this system, the diagnosis of presumed neonatal sepsis is established by the presence of three or more of the following criteria in the peripheral blood: Leukocytosis (>25,000) or Leukopenia (<5,000); increase in immature neutrophils; Immature-to-Mature (I:M) neutrophil ratio > 0.3; Immature-to-Total (I:T) neutrophil ratio > 0.2; platelet count less than or equal to 100.000/mm 3 ; and presence of major degenerative changes in neutrophils. The presence of two or fewer criteria is considered negative for diagnosis, and is associated with a 99% likelihood of sepsis being absent.