Tumor Necrosis Factor-α Gene Polymorphism in Hemodialysis Pediatric Patients: Association with Comorbidity, Functionality and Serum Albumin

The aim of this study was to evaluate the association between specific alleles genotypes of TNF-α with Index of Coexistent Disease (ICED) score (an index of comorbidity), karnofsky index (a measure of functional status), serum albumin and nutritional marker (body mass index) in 43 ESRD pediatric patients on regular HD. All participants were genotyped for TNF-308 promoter region polymorphism by PCR followed by digestion and gel electrophoresis. The TNF-α high producer genotype (A/A and G/A) had significantly higher comorbidity (ICED scores >=2) and lower functional scores compared with the TNF-α low producer genotype (G/G). Serum albumin levels were lower in patients with the TNF-α high producer genotype compared with those with the low producer genotype. Also body mass index was lower in the TNF-α high producer genotype compared with the TNF-α low producer genotype (p< 0.05). On multivariate analysis, the TNF-α high producer genotype was associated with increased significance for a higher ICED score, lower karnofsky index, lower serum albumin and lower body mass index compared with the low TNF-α low producer genotype (p< 0.05). Single nucleotide polymorphism in the promoter region of TNF-α show a strong association with indices of comorbidity, functionality, biological and nutritional markers in ESRD patients on long-term HD. The TNF-α high producer genotype seemed to be associated with adverse clinical outcome in ESRD patients. Prognostic TNF-α genetic assay provides a more precise approach for identification of high risk ESRD patients and development of accurate individualized treatment strategies.