Mannose-Binding Lectin 2 and Ficolin-2 Gene Polymorphisms Influence the Susceptibility to Bloodstream Infections in Kidney Transplant Recipients

IntroductionBoth mannose-binding lectin (MBL) and ficolin (FCN) interact with carbohydrate structures on microbial surfaces. Polymorphisms at the promoter and exon 1 of the MBL2 gene, which are responsible for low serum levels of MBL, have been shown to play important roles to increase the risk of post-transplant infections. Three gene polymorphisms in the promoter region of FCN2 and 2 in exon 8 (+6424 G > T) are associated with serum levels of FCN2 or binding capacity toward N-acetylglucosamine on microbial surfaces.MethodsWe prospectively analyzed 81 kidney transplant recipients for 6 well-known functional single-nucleotide polymorphisms in the MBL2 and 5 in the FCN2 gene of the recipients determined by gene sequencing. The bloodstream infections collected prospectively were associated with MBL2 and FCN2 genotypic variants over the first year after kidney transplantation.ResultsMultivariate analyses only found an association of recipient QQ + PQ genotypes of MBL2 5′-UTR +4 (odds ratio [OR] = 3.677, 95% confidence intervals [CI] = 1.127–11.998, P = .031) and FCN2 exon 8 Thr 236 Met(+6359 C > T) (OR = 4.917, 95% CI = 1.229–19.667, P = .024) with the incidence of bacteremia.ConclusionRecipient QQ + PQ genotypes of MBL2 5′-UTR +4 and recipient FCN2 exon 8 Thr 236 Met(+6359 C > T) variants showed significant impacts on the risk of developing bloodstream infections after kidney transplantation.