Kidney Injury Molecule-1 (KIM-1) is a type 1 transmembrane gly?coprotein with an immunoglobulin-like and mucin domain. It is expressed on the surface of tubular epi-thelial cells in the kidney.

KIM-1 levels are unde?tectable in normal kidneys, whereas elevated KIM-1 expression was detected in the ischemic kidney of patients. KIM-1 concentration in the urine of healthy humans is less than 1 ng/ml. Meanwhile, following the ischemic kidney injury it could be elevated up to 3-7 ng/ml. KIM-1 levels begin to increase as early as 6 hours after an ischemic insult and remain elevated for a period of 48 hours post-injury. Due to its simplicity and high specificity, KIM-1 may serve as a biomarker for renal proximal tubule injury facilitating the early diagnosis of the disease and serving as a diagnostic discriminator.