Diagnosis and treatment of acute tubular necrosis

Abstract

Background: Acute tubular necrosis (ATN) is common in hospitalized patients, particularly in the intensive care unit. Over the past four decades, the mortality rate from ATN has remained at 50% to 80%.

Purpose: To review recent studies of diagnosis and treatment strategies for ATN.

Data sources: MEDLINE search for all clinical studies of therapies for ATN, supplemented by a review of the references of the identified articles.

Study selection: Prospective studies and major retrospective studies evaluating therapies for ATN.

Data extraction: Data on the study sample, interventions performed, results, side effects, and duration of follow-up.

Data synthesis: Early diagnosis of ATN by exclusion of prerenal and postrenal causes of acute renal failure, examination of urinary sediment, and analysis of urine measures (for example, fractional excretion of sodium in the absence of diuretics) can allow the early involvement of nephrologists and improve survival. Enteral rather than parenteral hyperalimentation in severely malnourished patients may improve survival. Sepsis causes 30% to 70% of deaths in patients with ATN; therefore, avoidance of intravenous lines, bladder catheters, and respirators is recommended. Because septic patients are vasodilated, large volumes of administered fluid accumulate in the lung interstitium of these patients. This condition necessitates ventilatory support, which when prolonged leads to acute respiratory distress syndrome, multiorgan failure, and increased mortality. More aggressive dialysis (for example, given daily) with biocompatible membranes may improve survival in some patients with acute renal failure.

Conclusions: New information about the importance of early diagnosis and supportive care for patients with ATN has emerged. However, randomized trials of these interventions are needed to test their effect on the morbidity and mortality of ATN.