Nutritional status and intrarenal resistive indices after kidney transplantation.

BACKGROUND: Obesity predicts vascular stiffness, which is prevalent among kidney transplant patients. However, the influence of obesity has not been established on parameters of renal vascular resistance variation. The aim of this study was to analyze the influence of nutritional status on intrarenal resistive parameters as measured in the early period after successful kidney transplantation by Doppler ultrasound. METHODS: Both pulsatility index (PI) and resistance index (RI) in the kidney graft were measured by Doppler sonography twice: at 2 to 4 days and before hospital discharge (mean 22 days; 95% confidence interval 21-23) after transplantation. Nutritional status was scored according to World Health Organization criteria. RESULTS: Among 513 patients, 29 were underweight; 280, normal; 166, overweight; and 38, obese. Both PI and RI values were significantly increased consistent with recipient nutritional status (analysis of variance: P < .001). Post hoc analysis showed significant differences in PI and RI measurements for obese versus underweight or normal weight groups. Multivariate analysis revealed an influence of body mass index on PI and RI measurements before hospital discharge to be independent of other variables, including recipient age, prior delayed graft function and cold ischemia time. CONCLUSIONS: Excessive nutritional status was associated with increased renal vascular resistance among kidney transplant patients. Nutritional status should be considered for the proper interpretation of intrarenal Doppler measurements.

-174G/C interleukin-6 gene polymorphism and the risk of transplanted kidney failure or graft loss during a 5-year follow-up period.

The influence of cytokine gene polymorphisms on transplanted kidney outcome is not well understood. The aim of this one-centre study was to analyse the association between tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-10, interferon-γ (IFN-γ) and transforming growth factor-ß1 (TGF-ß1) genotypes and the incidence of delayed graft function (DGF), acute rejection (AR) and 5-year kidney graft loss. Genotyping was performed in 199 subsequent kidney graft recipients from deceased donors without induction therapy based on polymerase chain reaction method using sequence-specific primers for TNF-α (-308A/G), IL-10 (-1082A/G, -819T/C and -592A/C), IL-6 (-174G/C), IFN-γ (+874T/A) and TGF-ß1 (in codons 10T/C and 25G/C). Genotypes were grouped according to the strength of cytokine expression. During a 5-year follow-up period, 14 patients died with functioning graft and 33 developed graft failure. The analysed polymorphisms were not associated with the incidence of DGF. The frequency of early episodes of AR was significantly associated only with TGF-ß1 genotype. There was an association between -174G/C IL-6 gene polymorphism and the death-censored kidney graft survival. The risk of graft loss during 5-year follow-up period was greater by 57% for GG or GC (higher IL-6 production) than for CC carriers. None of the other analysed polymorphisms significantly influenced both patients and kidney graft survival, also in the analysis of the subgroup with human leucocyte antigen-DR mismatch. -174G/C IL-6 genotype of the kidney graft recipient could modulate the rate of graft excretory function deterioration and the risk of graft loss by influencing their constitutional expression.