TTR and chronic kidney disease: PEW is a proposed term to describe the state of decreased body stores of protein and energy that occurs in CKD and is diagnosed if three characteristics are present in four categories: (1) serum chemistry (low serum levels of albumin, prealbumin, or cholesterol), (2) reduced body mass (low BMI, weight loss, or low body fat percentage), (3) reduced muscle mass (muscle wasting, reduced mid-arm muscle circumference, or creatinine appearance), and (4) reduced dietary intake (low intake of protein or energy) [1].