Date Published: April 1, 2018
Publisher: JKL International LLC
Author(s): Erica Pires da Rocha, Lais Gabriela Yokota, Beatriz Motta Sampaio, Karina Zanchetta Cardoso Eid, Dayana Bitencourt Dias, Fernanda Moreira de Freitas, Andre Luis Balbi, Daniela Ponce.
Elderly is the main age group affected by acute kidney injury (AKI). There are no studies that investigated the predictive properties of urinary (u) NGAL as an AKI marker in septic elderly population. This study aimed to evaluate the efficacy of uNGAL as predictor of AKI diagnosis and prognosis in elderly septic patients admitted to ICUs. We prospectively studied elderly patients with sepsis admitted to ICUs from October 2014 to November 2015. Assessment of renal function was performed daily by serum creatinine and urine output. The level of uNGAL was performed within the first 48 hours of the diagnosis of sepsis (NGAL1) and between 48 and 96 hours (NGAL2). The results were presented using descriptive statistics and area under the receiver operating characteristic curve (AUC-ROC) and p value was 5%. Seventy-five patients were included, 47 (62.7%) developed AKI. At logistic regression, chronic kidney disease and low mean blood pressure at admission were identified as factors associated with AKI (OR=0.05, CI=0.01-0.60, p=0.045 and OR=0.81, CI=0,13-0.47; p=0.047). The uNGAL was excellent predictor of AKI diagnosis (AUC-ROC >0.95, and sensitivity and specificity>0.89), anticipating the AKI diagnosis in 2.1±0.3 days. Factors associated with mortality in the logistic regression were presence of AKI (OR=2.14, CI=1.42-3.98, p=0.04), chronic obstructive pulmonary disease (OR = 9.37, CI =1.79-49.1, p=0.008) and vasoactive drugs (OR=2.06, CI=0.98-1.02, p=0.04). The accuracy of NGALu 1 and 2 as predictors of death was intermediate, with AUC-ROC of 0.61 and 0.62; sensitivity between 0.65 and 0.77 and specificity lower than 0.6. The uNGAL was excellent predictor of AKI in septic elderly patients in ICUs and can anticipate the diagnosis of AKI in 2.1 days.
Seventy-five patients were included in the final analysis (Fig. 1). Mean age was 71.4 ± 7.53 years, 52% were male, most of them had comorbidities (65.4%), and hypertension, chronic kidney disease (CKD), cardiovascular disease, and diabetes mellitus were the most frequent (in 60, 49.3, 46.6, and 33.3% of patients, respectively). APACHE II score was 17.7 ± 6.89 and the need for mechanical ventilation and noradrenalin use in the first 24 hours after admission to ICU was 65.3 and 78.7%, respectively. The main source of infection was the lung (52%), followed by the urinary tract (24%). Forty-seven patients (62.7%) developed AKI and most of patients were classified as KDIGO 3 (43.5%), while KDIGO 1 occurred in 30.4% and KDIGO 2 in 28.1%. ATN-ISS was 0.63±0.25, acute renal replacement therapy was indicated in 5%, and mortality rate was 53.3%.
It is widely recognized that the incidence of AKI is increasing over time and is most common in elderly individuals. This is due to many reasons, including elderly are more likely to have renal structural decline and multiple comorbidities [24-27].