Acute renal failure (ARF) requiring renal replacement therapy (RRT) has been associated with an excess risk of mortality in adult patients with septic shock, but it is unknown whether this is also applicable to pediatric patients. We therefore conducted a retrospective pilot study. All children presenting with septic shock between 1st January 1998 and 1st April 2004 were analyzed. Patients with fluid refractory-dopamine resistant shock, necessitating the use of noradrenaline, were included. ARF was defined as the deterioration of renal function to the extent that renal replacement therapy was required (ARF group). This ARF group was compared with patients without ARF (non-ARF group). Out of the 22 children with severe septic shock, seven developed ARF. PIM2 and PRISM scores upon admission were comparable between both groups. Mortality rates were significantly higher in patients with ARF (57.1% vs 6.7%; p=0.02). Pediatric patients with severe septic shock developing ARF have excess mortality compared to pediatric patients who do not develop ARF, although on diagnosis, severity of underlying disease and calculated risk of mortality were comparable. A multicenter trial is necessary to confirm these findings and to determine the contribution of ARF to pediatric sepsis mortality.