Rantes –403g>a Functional Polymorphism and Upper Urinary Tract Infections in Children
Introduction Chemokines play a key-role in leukocytes recruitment in the site of inflammation, through the interaction with trans-membrane receptors. Genes that codify these chemokines and their receptors may present polymorphisms, which influence the proteins' level of expression and/or function. We have recently described an increased susceptibility to the development of acute pyelonephritis in children with interleukin 8 –251A > T polymorphism, presenting the first episode of upper urinary tract infection. Functional polymorphism of RANTES chemokine and its receptor CCR5 have been also identified. Material and Methods We carried out an association study of RANTES-403 G > A and CCR5Δ32 in 273 children with the first episode of upper urinary tract infection (UTI). Control population was represented by 326 blood umbilical cord DNAs coming from the same geographic area. Results Statistical analysis showed that RANTES-403 G > A phenotypic frequencies in the UTI group significantly differed from those of the control population (p = 0,007). A significant difference persisted when the genotype AA + GA was compared with the GG one (p = 0,002). Furthermore, comparing the frequencies observed in acute dimercaptosuccinic acid scan (DMSA)-positive and DMSA-negative patient with those observed in controls, a significant difference did emerge (p = 0,023 and p = 0,008 respectively). In addition, RANTES-403 G > A polymorphism frequency was significantly different in patients with vesico-ureteric reflux compared with the control population (p = 0,020). No difference were observed in the genotype distribution of CCR5Δ32 polymorphism. Conclusions Our results show that RANTES-403GG genotype is associated with an increased susceptibility to upper urinary tract infection.