Percentile charts of twin birthweight.

BACKGROUND: The birthweight of multiples is naturally lower than that of singletons. Given that the incidence of twin pregnancy has risen in recent years, it seems reasonable to create standards of birthweight separately for twins. This could help in the objective assessment of small and large for gestational age twin newborns. The main goal of this study was therefore to construct and present up-to-date birthweight references. METHODS: The present percentile charts for twins are based on a cohort retrospective study of 757 pairs of twins (767 boys and 709 girls) born between weeks 25 and 39 of gestation. Mean and standard deviation were calculated for the subsequent weeks of gestation. Percentiles were read for the subsequent gestational age. The obtained curves were smoothed with a fifth-degree polynomial function. The significance of differences between the 50th percentile values for twins and singletons was estimated using median test. RESULTS: In both sexes, a continuous observable trend occurs of a significantly lower average birthweight for twins. Differences increase with increasing gestational age and are greater in girls. The estimated 50th percentile for twins was greater than the estimated 10th percentile for singletons. This supports the notion of discordant growth as a physiological adaptation that promotes maturity. CONCLUSIONS: Percentile charts for singletons are not applicable for twins. This indicates the importance of applying separate percentile charts for twins, enabling objective evaluation of their health status and identifying deviations from normality.

Candidate gene analysis in pathogenesis of surgically and non-surgically treated necrotizing enterocolitis in preterm infants.

Necrotizing enterocolitis (NEC) is one of the most severe and unpredictable complications of prematurity. There are two possible mechanisms involved in the pathogenesis of NEC: individual inflammatory response and impaired blood flow in mesenteric vessels with secondary ischemia of the intestine. The aim of this study was to evaluate the possible relationship between polymorphisms: Il-1ß 3953C>T, Il-6 -174G>C and -596G>A, TNFα -308G>A, and 86 bp variable number tandem repeat polymorphism of interleukin-1 receptor antagonist (Il-1RN VNTR 86 bp) and three polymorphisms that may participate in arteries tension regulation and in consequence in intestine blood flow impairment: eNOS (894G>T and -786T>C) and END-1 (5665G>T) and NEC in 100 infants born from singleton pregnancy, before 32 + 0 weeks of gestation, exposed to antenatal steroids therapy, and without congenital abnormalities. In study population, 22 (22%) newborns developed NEC. Surgery-requiring NEC was present in 7 children. Statistical analysis showed 20-fold higher prevalence of NEC in infants with the genotype TT [OR 20 (3.71-208.7); p = 0.0004] of eNOS 894G>T gene polymorphism. There was a higher prevalence of allele C carriers of eNOS 786T>C in patients with surgery-requiring NEC [OR 4.881 (1.33-21.99); p = 0.013]. Our investigation did not confirm any significant prevalence for NEC development in another studied genotypes/alleles. This study confirms the significant role of polymorphisms that play role in intestine blood flow. Identifying gene variants that increase the risk for NEC development may be useful in screening infants with inherent vulnerability and creating strategies for individualized care.

The significance of IL-1ß +3953C>T, IL-6 -174G>C and -596G>A, TNF-α -308G>A gene polymorphisms and 86 bp variable number tandem repeat polymorphism of IL-1RN in bronchopulmonary dysplasia in infants born before 32 weeks of gestation.

INTRODUCTION: Bronchopulmonary dysplasia (BPD) is a chronic lung disease that affects primarily preterm infants. Genetic factors are also taken into consideration in the pathogenesis of BPD. Genetic predispositions to higher production of inflammation mediators seem to be crucial. MATERIAL AND METHODS: The aim of this study was to evaluate the possible relationship between polymorphisms: interleukin-1ß +3953 C>T, interleukin-6 -174 G>C and -596 G>A, tumour necrosis factor -308 G>A and interleukin-1RN VNTR 86bp and the occurrence of BPD in a population of 100 preterm infants born from singleton pregnancy, before 32+0 weeks of gestation, exposed to antenatal steroids therapy, and without congenital abnormalities. RESULTS: In the study population BPD was diagnosed in 36 (36%) newborns. Among the studied polymorphisms we found the higher prevalence for BPD developing of the following genotypes: 1/2 (OR 1.842 [0.673-5.025] and 2/2 IL-1RN (OR 1.75 [0.418-6.908] 86bpVNTR; GC (2.222 [0.658-8.706]) and CC IL-6 -174G>C (1.6 [0.315-8.314]) and GA (2.753 [0.828-10.64]) and AA (1.5 [0.275-8.067] IL-6 -596G>A), GA 1.509 (0.515-4.301) TNF-α -308G>A. However, these finding were not statistically significant. CONCLUSIONS: Genetic factors are undeniably involved in the pathogenesis of BPD. In the times of individualised therapy finding genes responsible for BPD might allow the development of new treatment strategies. A new way of specific therapy could ensure the reduction of complications connected with BPD and treatment costs.