PURPOSE: One of the common causes of neonatal respiratory distress is congenital pneumonia. Angiotensin-converting enzyme (ACE) is a component of the renin-angiotensin system and plays a significant role in blood pressure regulation and in fluid and electrolyte homeostasis. The lung endothelial cells in particular produce this enzyme. So it may have role in pathogenesis of pneumonia.The ACE gene contains the insertion/deletion polymorphism within exon 16, which show association with some cardiovascular diseases. Plasma ACE level are known to be elevated in subjects with allele D of the ACE gene compared with heterozygous or homozygous for the I allele. In term and even preterm infants ACE levels is elevated too.We investigated the association between the ACE genotype and alleles and the incidence of congenital pneumonia.
METHODS: The DNA samples from cord blood of Caucasian infants, admitted to the neonatal intensive care units at Ufa City Clinical Hospital №17, who had clinical signs of congenital pneumonia (CP) and needed for respiratory support (82 babies) and the control group consisted of 103 Caucasian healthy babies born in Ufa, Russia during the years 2003-2005 used for studying the ACE ins/del polymorphism by PCR method.Comparisons of allele and genotype frequencies were performed by two-tailed X2 test with Statistica v. 6.0 program. Differences were considered significant at the P<0.05 level.
RESULTS: The II genotype was found in patient group only in 18.3% of cases while in 35.9% of cases in control (OR=0.4, 95%CI 0.2-0.8, p=0.01). The frequency of D allele was markedly increased in CP group compared with control group (53.1% vs. 40.8%, OR=1.64, 95%CI 1.1-2.5, X2=5.05, p=0.02).
CONCLUSION: The II genotype of ACE gene has possible protective role for pneumonia in neonates. And the D allele is strongly associated with susceptibility in congenital pneumonia. So, angiotensin-converting enzyme polymorphism shares the development of inflammatory disease in neonates.
CLINICAL IMPLICATIONS: The recognizing of the mutant allele carriers at the early stage of disease can improve the treatment of the neonates with pneumonia.
DISCLOSURE: Kseniya Danilko, None.