Role of the kidney in plasma cytokine removal in sepsis syndrome: A pilot study

Background: At the onset of sepsis, endotoxins or other components of the gram-negative capsular wall stimulate the synthesis of pro-inflammatory cytokines by activating the monocyte-macrophage system. In this context, interleukin-1 beta (IL-1), tumor necrosis factor-alpha (TNF) and IL-6 are considered co-responsible for the clinical picture of sepsis syndrome. Many organs can be involved, and kidney dysfunction occurs early with a picture of non-oliguric acute renal failure (NOARF) or oliguric acute renal failure (OARF). This study aimed to investigate the role of the kidney in plasma removal of some pro-inflammatory cytokines in the first 24 hr after the diagnosis of sepsis syndrome, when, according to the peak concentration hypothesis, their plasma concentration is maximal. 18 septic patients, six patients with normal renal function (NRF), six with NOARF and six with OARF were selected for the study. We measured the plasma levels and urinary excretion of IL-1, TNF and IL-6 at the moment of sepsis diagnosis (baseline) and 24 hr later. Moreover, urinary excretion of IL-1 and LL-6 was done in the same interval by measuring the percentage of fractional excretion (FE%) of these cytokines. Results: Multivariate analysis (ANOVA) showed no significant difference in plasma IL-1 levels at baseline in the NRF, NOARF and OARF patients (p=0.11), whereas a significant increase was found in OARF patients at 24 hr, p