Assessment of tumor necrosis factor alpha polymorphism TNF-α−238 (rs 361525) as a risk factor for development of acute kidney injury in critically ill patients

Critically ill patients revealed significant adverse outcomes (sepsis, septic shock, organ dysfunction/failure, and mortality) despite variable effort. Aim: this study evaluated the association of TNF-a−238 (rs 361525) with adverse outcomes in critically ill patients. TNF-α−238 (rs 361525) SNP was performed by RT-PCR on 200 critically-ill patients (112 had severe sepsis and septic shock and 88 were septic), 127 of them had AKI. Urinary N-acetyl-β-(d)-glucosaminidase and serum creatinine were assessed by modified Jaffé and ELISA respectively. These results revealed that heterozygous genotype GA of TNF-α−238 (rs 361525) SNP significantly increased the risk of adverse-outcome (mortality rate) (P = 0.0001; OR 8.9), regardless of organ dysfunction (P = 0.09) or severity of sepsis (P = 0.6). Moreover, heterozygous genotype GA of TNF-α−238 (rs 361525) SNP was significantly associated with inflammatory marker (sTNF-α) (P = 0.014) and tubular injury marker (uNAG) (P = 0.001) that displayed a significant association with severity of sepsis (0.001, 0.035) and organ dysfunction (0.012, 0.0001) respectively. In critically ill patients with sepsis induced AKI, serum TNF-α and uNAG measured at admission can predict severity of sepsis and AKI (defined by REFILE) occurrence along with pre-existing CKD and DM. However, TNF−238 yielded additional prognostic information on ICU mortality irrelevant to AKI in septic patients.