Nitric Oxide Synthase 2 Promoter Polymorphism Is a Risk Factor for Allergic Asthma in Children.

Background and Objectives: In paediatric population, atopic asthma is associated with increased eosinophil counts in patients, that correlate with the airway inflammation measured by the concentration of nitric oxide in exhaled air (FeNO). As the FeNO level is a biomarker of atopic asthma, we assumed that polymorphisms in nitric synthases genes may represent a risk factor for asthma development. The purpose of this study was to analyse the association of NOS genetic variants with childhood asthma in the Polish population. Materials and methods: In study we included 443 children-220 patients diagnosed with atopic asthma and 223 healthy control subjects. We have genotyped 4 single nucleotide polymorphisms (SNP) from 3 genes involved in the nitric oxide synthesis (NOS1, NOS2 and NOS3). All analyses were performed using polymerase chain reaction with restriction fragments length polymorphism (PCR-RFLP). Results: We observed significant differences between cases and controls in SNP rs10459953 in NOS2 gene, considering both genotypes (p = 0.001) and alleles (p = 0.0006). The other analyzed polymorphisms did not show association with disease. Conclusions: According to our results, 5'UTR variant within NOS2 isoform may have an impact of asthma susceptibility in the population of Polish children. Further functional studies are required to understand the role of iNOS polymorphism in NOS2 translation and to consider it as a novel risk factor in childhood asthma. The next step would be to apply this knowledge to improve diagnosis and develop novel personalized asthma therapies.

Morphological and molecular diagnosis of a fatal form of EBV infectious mononucleosis in a child.

Mortal cases of acute Epstein-Barr virus (EBV) infection in the form of mononucleosis have been seldom described and used to be related to complications of the disease. In this report, the case of a 3-year-old girl is described, with severe form of infectious mononucleosis, deceased in the course of respiratory-circulatory insufficiency with a sudden cessation of heart action. Particular attention was given to histological lesions, phenotype of inflammatory cells and to expression of proteins and EBV RNAs (EBERs) in tissues, examined using immunocytochemical techniques and in situ hybridization. Histological patterns were dominated by massive lymphocyte infiltrates (mostly CD45RO+ and CD3+ cells), mainly in lungs and in liver and, less pronounced, in kidneys and in leptomeninx. Lymphocyte proliferation exhibited polyclonal character: both lambda and kappa chains were present. No myeloblastic differentiation could be demonstrated. The EBV proteins, as well as EBV RNAs (EBERs) were detected both in small lymphocytes B and in enlarged (blast) cells, frequently resembling Reed-Sternberg cells. In our tissue material co-expression of the two proteins (EBNA2+, LMP1+) and EBER has been demonstrated in every organ, in accordance to the latency III pattern described by other authors.