Soluble E-selectin, soluble L-selectin and soluble ICAM-1 in bronchopulmonary dysplasia, and changes with dexamethasone.

OBJECTIVE: To evaluate longitudinal change in arterial blood plasma levels of soluble adhesion molecules in infants of <30 weeks' gestation with respiratory distress syndrome (RDS) and to look for differences in these levels in neonates who subsequently developed bronchopulmonary dysplasia (BPD) compared with those neonates who did not, and also to investigate the effect of dexamethasone treatment on levels of soluble adhesion molecules in plasma. METHODS: We measured plasma concentrations of soluble L-selectin (sL-selectin), soluble E-selectin (sE-selectin), and soluble intercellular adhesion molecule-1 on days 1, 3, 7, 14, 21, and 28 of life and before and 2 to 3 days after initiating a 6-day course of dexamethasone treatment. Infants with RDS were followed until discharge and were classified as non-BPD and either 1) BPD day 28 reflecting oxygen requirement on day 28 but not at 36 corrected weeks or 2) BPD 36 weeks reflecting oxygen requirement at 36 (corrected) weeks' gestation. The classification of presence or absence of BPD by oxygen requirement was supported by and was consistent with radiologic findings of BPD for all infants. The difference between BPD day 28 and BPD 36 weeks was supported by more extensive radiologic effects in the latter. RESULTS: The arterial plasma level of sL-selectin in infants who had RDS and did not develop BPD was significantly decreased compared with term healthy infants, as was the level of sE-selectin. Compared with infants who had RDS and did not develop BPD, sL-selectin levels were even further decreased in infants who had RDS and did develop BPD both at birth and throughout the first 4 weeks of life (day 1 through day 28). Infants with BPD also showed increasing levels of sE-selectin during this period of time, whereas infants without BPD did not. Levels of soluble intercellular adhesion molecule-1 in infants without BPD were not different from infants with BPD initially but increased in infants with BPD compared with infants without BPD, significant on day 28 in both groups. Dexamethasone treatment increased concentration of sL-selectin and decreased concentration of sE-selectin. CONCLUSIONS: Low sL-selectin may be an early indicator of enhanced risk for BPD. Low levels of sL-selectin and increasing levels of sE-selectin may be risk factors for BPD. The effects of dexamethasone treatment include significant modulation of adhesion molecules.

Neonatal outcome of triplet versus twin and singleton pregnancies: a matched case control study.

OBJECTIVE: To determine the neonatal outcome of triplet gestations versus that of singletons and twins matched for gestational age. STUDY DESIGN: All live born triplet gestations delivered between 1 April 1993 and 31 March 2000 were compared to an age matched control group consisting of live born twins and singletons. The neonatal outcome of 116 sets of triplets was compared to that of 116 sets of twins and 116 singletons. RESULTS: During a 7-year period 116 sets of triplet pregnancies were reviewed. Of 116 sets of live born triplets (348 newborns), 70.67% triplets were born between 33- and 36-week gestation, 28.44% between 28 and 32 weeks and 0.86% less than 28 weeks. Triplets were smaller in weight than singletons but not twins. Apgar score, use of prenatal steroid and sex ratio were similar in the three groups. Incidence of respiratory distress syndrome (RDS), use of surfactant, infants requiring intubation, pneumothorax, patent ductus arteriosus, sepsis, intraventricular hemorrhage, periventricular leucomalacia, retinopathy of prematurity, necrotizing enterocolitis, gastroesophageal reflux and jaundice requiring phototherapy were not statistically different among the three groups. Incidence of major and minor congenital anomalies, percent neonatal intensive care unit (NICU) admissions, and mean duration of NICU stay were also similar. There was no influence of birth order on neonatal outcome of triplet pregnancy and outcome did not significantly change over 7 years of the study period. CONCLUSIONS: Triplets have a similar outcome to twins and singletons when matched for gestational age. Since outcome is dependent on gestational age, the closer the gestational age is to term the better is the outcome.

Lymphocyte subpopulations in bronchopulmonary dysplasia.

A key role for inflammation in the etiology of bronchopulmonary dysplasia (BPD) has been proposed. In the present study we have evaluated lymphocyte subpopulations in 39 premature infants with respiratory distress syndrome (RDS) who did or did not develop BPD. The absolute number of lymphocytes was lower among infants with RDS who developed BPD compared with those who did not over the first two weeks of life ( p < 0.020) as were percentage and absolute number of CD4(+) T cells. By contrast, the proportions of CD3(+)CD8(+) lymphocyte cells were not statistically different between non-BPD and BPD infants. B cell percentage was significantly decreased in BPD infants only on day 7. NK "bright" cells (CD56(+)) were highly enriched in all RDS groups. Interestingly, the percentage of CD4(+) T cells expressing CD62L was selectively reduced in BPD infants. As a whole these data suggest that reduction of CD4(+) T cells and especially those important in tissue migration and immune surveillance may be a factor in the pathogenesis of BPD.