Tumor necrosis factor gene polymorphism and septic shock in surgical infection.

Abstract

To evaluate the relationship of the genotype distribution of the tumor necrosis factor (TNF)-alpha polymorphism with regard to the plasma TNF-alpha concentration and the development of septic shock as well as mortality of infected patients in a surgical intensive care unit (SICU). A total of 112 postoperative critically ill infected patients were prospectively enrolled. SICU of a tertiary university-affiliated medical center. Patients who were consecutively admitted to the SICU because of surgical infection with sepsis. Blood sampling. Blood sample was obtained 24 hrs after intensive care unit (ICU) admission or within 2 hrs after the onset of septic shock to determine the plasma TNF-alpha level and to analyze the genotype of the biallelic polymorphism of the TNF-alpha. The allele frequency of the TNF2 in our infected ICU patients was 12%. Forty-two (37.5%) patients admitted fulfilled the criteria of septic shock during their ICU stay. Patients carrying the TNF2 allele were not more likely to develop septic shock, nor did they have a higher mortality rate. In the patients with septic shock, those carrying the TNF2 allele had a significantly higher mortality rate than those with the homozygous TNF1 genotype (92% vs. 62%, p < .05). In those who developed septic shock, the TNF2 allele was significantly associated with higher TNF levels. In patients admitted to SICU with surgical infection, the frequency of TNF2 allele was higher than in the general population. SICU patients with TNF2 allele did not show a higher incidence of developing septic shock, nor was there a higher baseline TNF-alpha level after infection. However, once septic shock had developed, the mortality rate was higher in those patients carrying the TNF2 allele.