Long-term outcome of acute tubular necrosis: A contribution to its natural history

Abstract

As long-term outcome studies of acute renal failure (ARF) are scarce and non-homogeneous, we studied 187 consecutive acute tubular necrosis (ATN) patients without previous nephropathies, discharged alive from our hospital between October 77 and December 92 and followed-up until December 99 (range 7-22 years; median 7.2). Variables were analyzed at the time of the acute episode and during follow-up. In 2000-2001 a clinical evaluation was made in 58 of the 82 patients still alive. Ten patients were lost to follow-up and 95 died. In 59% death was related with the disease present when the ATN developed. Kaplan-Meir survival curve showed 89, 67, 50, and 40% at 1, 5, 10, and 15 years, respectively, after discharge. Survival curves were significantly better (log-rank P<0.001) among the youngest, those surviving a polytrauma, those without comorbidity and surprisingly those treated in intensive care units. The proportional Cox model showed that age (hazard ratio (HR) 1.04 per year of age; P=0.000), presence of comorbid factors (HR 4.29; P=0.006), surgical admission (HR 0.45; P=0.000), and male sex (HR 1.72; P=0.020) were the variables associated with long-term follow-up. In the evaluated patients renal function was normal in 81%. Long-term outcome after ARF depends on absence of co-morbid factors, cause of initial admission and age. Although the late mortality rate is high and related with the original disease, renal function is adequate in most patients.

Predictors of Recurrent AKI

“…The latter may be especially critical during recovery from AKI, which can often be prolonged. [11][12][13][14] Traditional AKI risk stratification often focuses on static susceptibility risk factors including age or CKD. While important, these findings indicate that the risk for AKI is dynamic and varies greatly as underlying disease evolves.…”

“…The rationale for the latter was to account for recovery of kidney function, which several studies have found can extend up to months following an episode of AKI. [12][13][14] Data Sources…”

Nonrecovery of Kidney Function and Death after Acute on Chronic Renal Failure

“…Previous studies of long-term outcomes after ARF did include patients with preexisting CKD; however, virtually all previous studies were limited by lack of a control (non-ARF) population (i.e., they were designed as case series and not as cohort studies) (32)(33)(34)(35)(36). They also often had limited generalizability as a result of the nature of the patients studied (e.g., only patients who were treated with continuous renal replacement therapies [32], only those who were in the intensive care unit [34,35]).…”

Delayed Graft Function and the Risk for Death with a Functioning Graft

“…[12][13][14][15] These adverse effects may partially contribute to the poor long-term survival observed in patients who have AKI and eventually recover renal function. 16,17 Similar to AKI, DGF in KTR is associated with the modulation of leukocyte/endothelial function, upregulation of cytokines/adhesion molecules, and increase in markers of oxidative stress. 18 The combination of ischemiareperfusion injury, donor procurement injury, and immunosuppressive therapy in the setting of uremia all may participate in creating an unfavorable recipient milieu that has implications for long-term survival.…”