Urine biochemistry assessment in the sequential evaluation of renal function: Time to think outside the box

Abstract

Urine biochemistry (UB) remains a controversial tool in acute kidney injury (AKI) monitoring, being considered to be of limited value both in terms of AKI diagnosis and prognosis. However, many criticisms can be made to the studies that have established the so called “pre-renal paradigm” (used for decades as the essential physiological basis for UB assessment in AKI) as well as to more recent studies suggesting that UB has no utility in daily clinical practice. The aim of this article is to describe our hypothesis on how to interpret simple and widely recognized urine biochemical parameters from a novel perspective, propose the rationale for their sequential assessment and demonstrate their usefulness in AKI monitoring, especially in the critical care setting.

Determination of Sodium, Potassium, Calcium and Magnesium in Urine, Using Microwave Plasma - Atomic Emission Spectrometry and Multi-Energy Calibration

“…Mean ± SD, mg L -1 Dilution (1) Std., mg L - (1) urine dilution factor corresponds to the final solution prepared for multi-energy calibration (solution M); (2) concentration of the added standard in the final solution used in MEC (M+S); (3) regression coefficient on the above function; (4) slope of linear regression relating signal intensities in M and M+S solutions at different spectral lines, the presented value is a mean from three replicates (Eq. 1).…”

“…Sodium, potassium, calcium, and magnesium are major cationic urinary electrolytes; their monitoring serves for dietary intake control and as a diagnostic tool in many clinical conditions associated with osmotic balance, renal, muscle and heart functions, among others [1,2]. Given the importance of the four metals in human health and disease, their determination is performed in both, clinical and research laboratories.…”

The Plastic Within: Microplastics Invading Human Organs and Bodily Fluids Systems

“…It is a transparent to pale-yellow fluid that varies in color depending on an individual's hydration levels and dietary intake. Urine is composed of approximately 95% water, making it an essential component of the body's waste removal system [74]. The characteristics of urine, such as color, odor, and frequency of urination, can provide valuable insights into an individual's hydration status and overall health [74].…”

Efficacy of blood urea nitrogen-to-albumin ratio for predicting prognostic outcomes of inpatients with COVID-19: A meta-analysis

“…While an increase in BUN is usually associated with high-protein diet, hypovolemia, gastrointestinal hemorrhage, increased catabolism, and a reduction in glomerular filtration rate, its concentration may decrease in individuals with syndrome of inappropriate antidiuretic hormone, severe liver disease, as well as those in an anabolic state. [11,12] Albumin, which is the most abundant (i.e., over 50%) plasma protein synthesized by hepatocytes, has a normal concentration between 3.5 g/dL and 5 g/dL. In addition to its role as a major modulator of plasma oncotic pressure, it acts as a transporter of endogenous (e.g., metabolites) and exogenous (i.e., drugs) ligands.…”