Acute renal failure (ARF) is a state that endangers the life of patients. The patient outcome is dependant upon on many factors such as: patient age, the cause of renal failure, the degree of demage to the parenchyma, the methods and the speed of treatment, and many factors not always known.Tests on finding a relationship between certain factors and the prognosis have not proved successful. Not much is known about the long-term follow-up of ARF in children who have survived the acute phase of the disease. The analysis incorporated 118 children. Their ages ranged from 3 days postpartum to 5 years. All subjects were diagnosed with acute renal failure. The analysis was conducted on children by taking an initial patient history and then by follow-up out-patient control.It was determined that ARF had the highest percentage of occurrence in infants, with males having a higher rate of occurrence. The most commonly observed cause of ARF was hypovolemia, associated mostly with either diarrhea or with hemolytic-uremic syndrom (HUS). It was determined that a failure in the urinary system beyond the kidneys (post-renal) occurred only during the first year of life. Beyond that time, the nephrotic syndrom was most commonlyu observed with ARF. There was no concrete evidence for any relationship between a patient's age, the cause of ARF, and the developement of the acute phase of the illness. Severe cases of ARF (according to Giananton's criterium) dominated in the 2 year old age group and were not observed in patients above 3 years of age. It was determined that this form of ARF occured only in patients with HUS. It was shown that treatment by dialysis was most often associated with the advanced acute phase. In this study 33.9% of the sample group were treated with dialysis.

Keywords: acute renal failure, children, long-term follow-up treatment