Renal recovery

Acute Kidney Injury Recovery Patterns in ST-Segment Elevation Myocardial Infarction Patients

Background: Acute kidney injury (AKI) is a frequent complication in patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI). Identification of different AKI recovery patterns may improve patient prognostic stratification. We investigated the clinical relevance of AKI recovery patterns among STEMI patients undergoing PCI. Methods: A retrospective study of 2943 STEMI patients undergoing PCI. The incidence of renal impairment, in-hospital complications, short and long-term mortality, were compared between patients without AKI, with early recovery defined as a return to baseline creatinine within 72 h, and no AKI recovery/delayed recovery defined as all other AKI cases. Results: A total of 255 (8.7%) patients developed AKI, of whom 124/255 (49%) patients had an early recovery, whereas 131/255 (51%) had no AKI recovery/delayed recovery. Patients without recovery were more likely to have in-hospital complications and higher long-term mortality (36.64% vs. 7.25%%; p < 0.001). In a multivariable regression model, the mortality hazard ratio (HR) for long term mortality remained significant for patients with no/delayed recovery AKI (HR 7.76, 95% CI 4.69 to 12.86, p < 0.001), and a strong trend among patients with resolving AKI (HR 2.09, 95% CI 0.933−4.687, p = 0.071). Conclusions: Among STEMI patients undergoing PCI, the recovery pattern of AKI is a valuable prognostic marker.

Development and validation of a novel prediction model for predicting renal function recovery after diversion in patients with obstructive uropathy

OBJECTIVE

To develop and validate a novel prediction model predicting renal function recovery following diversion in patients with obstructive uropathy (OU) to the emergency department (ED).

METHODS

After a systematic literature search, a novel prediction model called PGIMER Obstructive Uropathy Score (POUS) was constructed including five variables: age (<60 or >60 years), duration of symptoms (<4 or >4 weeks), presence of solitary functioning kidney, baseline hemoglobin levels and venous blood pH. This model was then validated in a prospective, observational single-center study of patients presenting with OU caused by various etiologies. Patients with OU and raised serum creatinine (>2 mg/dL) presenting to our ED were included. Renal function recovery was defined as creatinine value <1.5 mg/dL at 4 weeks following diversion.

RESULTS

In this study, 174 consecutive patients with OU were recruited, and 74 (42.5%) patients had renal function recovery. All the variables included in the POUS were noted to be statistically significant on univariate analysis. On multivariate logistic regression analysis, only POUS was identified as an independent predictor of renal function recovery. On receiver operating curve analysis, the area under the curve for POUS was 0.832 for predicting recovery. A POUS of 5 or more had specificity and sensitivity of 83% and 73.6%, respectively, in predicting renal function recovery. The goodness of fit and calibration plots showed good concordance of the predicted values with the observed values.

CONCLUSIONS

The POUS model is an accurate and simple-to-use tool for predicting renal function recovery. POUS model requires external validation prior to clinical use in different populations.

Biomarkers of persistent renal vulnerability after acute kidney injury recovery

Acute kidney injury (AKI) is a risk factor for new AKI episodes, chronic kidney disease, cardiovascular events and death, as renal repair may be deficient and maladaptive, and activate proinflammatory and profibrotic signals. AKI and AKI recovery definitions are based on changes in plasma creatinine, a parameter mostly associated to glomerular filtration, but largely uncoupled from renal tissue damage. The evolution of structural and functional repair has been incompletely described. We thus aimed at identifying subclinical sequelae persisting after recovery from cisplatin-induced AKI in rats. Compared to controls, after plasma creatinine recovery, post-AKI kidneys showed histological alterations and attendant susceptibility to new AKI episodes. Tubular function (assessed by the furosemide stress test, FST) also remained affected. Lingering parenchymal and functional subclinical alterations were paralleled by tapering, but abnormally high levels of urinary albumin, transferrin, insulin-like growth factor-binding protein 7 (IGFBP7), tissue inhibitor of metalloproteinases-2 (TIMP-2) and, especially, the [TIMP-2]*[IGFBP7] product. As subclinical surrogates of incomplete renal recovery, the FST and the urinary [TIMP-2]*[IGFBP7] product provide two potential diagnostic tools to monitor the sequelae and kidney vulnerability after the apparent recovery from AKI.

Acute kidney disease and long-term outcomes in critically ill acute kidney injury patients with sepsis: a cohort analysis

BACKGROUND

Acute kidney injury (AKI) is frequent during hospitalization and may contribute to adverse short- and long-term consequences. Acute kidney disease (AKD) reflects the continuing pathological processes and adverse events developing after AKI. We aimed to evaluate the association of AKD, long-term adverse renal function and mortality in a cohort of patients with sepsis.

METHODS

We performed a retrospective analysis of adult patients with septic AKI admitted to the Division of Intensive Medicine of the Centro Hospitalar Lisboa Norte (Lisbon, Portugal) between January 2008 and December 2014. Patients were categorized according to the development of AKI using the Kidney Disease: Improving Global Outcomes (KDIGO) classification. AKI was defined as an increase in absolute serum creatinine (SCr) ≥0.3 mg/dL or by a percentage increase in SCr ≥50% and/or by a decrease in urine output to <0.5 mL/kg/h for >6 h. AKD was defined as presenting at least KDIGO Stage 1 criteria for >7 days after an AKI initiating event. Adverse renal outcomes (need for long-term dialysis and/or a 25% decrease in estimated glomerular filtration rate after hospital discharge) and mortality after discharge were evaluated.

RESULTS

From 256 selected patients with septic AKI, 53.9% developed AKD. The 30-day mortality rate was 24.5% (n = 55). The mean long-term follow-up was 45.9 ± 43.3 months. The majority of patients experience an adverse renal outcome [n = 158 (61.7%)] and 44.1% (n = 113) of patients died during follow-up. Adverse renal outcomes, 30-day mortality and long-term mortality after hospital discharge were more frequent among AKD patients [77.5 versus 43.2% (P < 0.001), 34.1 versus 6.8% (P < 0.001) and 64.8 versus 49.1% (P = 0.025), respectively]. The 5-year cumulative probability of survival was 23.2% for AKD patients, while it was 47.5% for patients with no AKD (log-rank test, P < 0.0001). In multivariate analysis, AKD was independently associated with adverse renal outcomes {adjusted hazard ratio [HR] 2.87 [95% confidence interval (CI) 2.0-4.1]; P < 0.001} and long-term mortality [adjusted HR 1.51 (95% CI 1.0-2.2); P = 0.040].

CONCLUSIONS

AKD after septic AKI was independently associated with the risk of long-term need for dialysis and/or renal function decline and with the risk of death after hospital discharge.