Acute Kidney Failure

Background: Acute kidney injury (AKI) is common in critically ill patients and is associated with worse outcomes, including longer ICU stay, need for dialysis, and higher mortality. Patients with AKI often experience significant protein and calorie loss due to their illness and medical treatments. Providing the right amount of protein may help maintain muscle mass and improve recovery; however, consuming too much protein could potentially worsen kidney function. Current international guidelines recommend adequate protein intake, but the best dose remains uncertain, especially for patients with AKI. Study Purpose: This research will examine whether patients with AKI who receive a higher protein intake (greater than 1.2 g/kg/day) have different outcomes compared to those who receive a standard or lower protein intake (≤1.2 g/kg/day). The primary outcome is whether a higher protein intake leads to a longer recovery time from AKI or worsens kidney function. Study Design: This is a retrospective, multicenter study using data from five hospitals in Argentina. It is designed as a "target trial emulation," meaning researchers will analyze existing patient data as if it were a randomized clinical trial. Patients will be included on the fifth day of their ICU stay and classified into two groups based on their protein intake on day 5: * Group 1 (Standard Protein): ≤1.2 g/kg/day * Group 2 (High Protein): \>1.2 g/kg/day No additional interventions will be performed; data are collected from medical records. Study Population: The study will include adult patients (≥18 years) admitted to the ICU who are receiving exclusive enteral or parenteral nutrition and have AKI (or worsening chronic kidney disease) according to KDIGO criteria. Patients with advanced chronic kidney disease (creatinine clearance \<30 ml/min/1.73 m²) or undergoing hemodialysis at T0, previous kidney transplant, severe liver disease, or BMI \>30 will be excluded. Outcomes: * Primary Outcome: Time to recovery of kidney function within 30 days, measured by creatinine returning close to baseline values. * Secondary Outcomes: Changes in blood urea levels, duration of renal replacement therapy (hemodialysis), ICU length of stay, and 30-day mortality. Statistical Approach: To minimize bias, the study will use advanced statistical methods, including propensity score weighting, to ensure fair comparison between groups. Competing risks (such as death before kidney recovery) will be taken into account in the analysis. Significance: This study will provide important information about the safety and effectiveness of higher protein intake in critically ill patients with AKI. The findings may help guide nutritional strategies in the ICU, optimize kidney outcomes, and improve patient care.

Acute kidney injury (AKI) and chronic kidney disease (CKD) impose a significant global health burden. Yet, no effective therapies currently exist for AKI, and only a few are available for CKD. Despite significant effort from industry and academia, development of pharmacologic therapies for AKI and CKD has been hampered by: Non-predictive animal models The inability to identify and prioritize human targets The limited availability of human kidney biopsy tissue A poor understanding of AKI and CKD heterogeneity Historically, AKI and CKD have been described as single, uniform diseases. However, growing consensus suggests that different disease pathways lead to different subgroups of AKI and CKD (AKIs and CKDs). Access to human kidney biopsy tissue is a critical first step to define disease heterogeneity and determine the precise molecular pathways that will facilitate identification of specific drug targets and ultimately enable individualized care for people with AKI and CKD. A number of research centers across the United States are collaborating to bring state-of-the-art technologies together to: * Ethically obtain and evaluate kidney biopsies from participants with AKI or CKD * Define disease subgroups * Create a kidney tissue atlas * Identify critical cells, pathways, and targets for novel therapies The KPMP is made up of three distinct, but highly interactive, activity groups: * Recruitment Sites: The recruitment sites (RS) are responsible for recruiting participants with AKI or CKD into the longitudinal study and performing the kidney biopsy. * Tissue Interrogation Sites: The tissue interrogation sites (TIS) are responsible for developing and using innovative technologies to analyze the biopsy tissue. * Central Hub: The central hub is responsible for aggregating, analyzing, and visualizing the generated data and providing scientific, infrastructure, and administrative support for the KPMP consortium.

Acute kidney injury (AKI) is a significant postoperative complication. Risk factors for AKI include impaired renal perfusion, decreased functional renal reserve, as well as advanced age, peripheral arterial disease, diabetes mellitus, renovascular disease and congestive heart failure. Mean arterial pressure (MAP) below 55-60 mmHg has been associated with postoperative AKI. Traditional diagnostic criteria for AKI include increased serum creatinine levels and oliguria. However, creatinine levels do not rise until more than half of renal function is lost. Serum and urine NGAL levels rise earlier-within 24-48 hours-making it a promising early biomarker. In our study, hypotension is defined as systolic blood pressure \<100 mmHg or a \>30% decrease in MAP. Patients requiring ephedrine under these conditions will be evaluated as the hypotension group and compared with non-hypotensive patients in terms of NGAL, BUN (blood urea nitrogen), creatinine, and GFR (Glomerular Filtration Rate) values at baseline and at the 4th postoperative hour.

The assessment of AI -based prediction models in detecting AKI early in critically ill patients. Specifically, the aim is to evaluate the model's ability to predict the onset of AKI before it clinically manifests allowing for early interventions