Casts (CAST)
Casts are cylindric urinary particles, originating from the renal tubules by secretion of the Tamm-Horsafall protein and small amounts of plasma albumin. Casts are differentiated into hyaline and pathological casts.
Hyaline casts (Hy.CAST)
Hyaline casts are colourless and translucent and appear with two parallel sides and two, often rounded ends, but morphology can vary. Hy.CAST are also observed in healthy individuals, e.g. in context of extensive activity. They are of relevance in kidney disease patients, where they are observed in increased numbers, as well as in hypertension and people with reduced flow rates.
Pathological casts (Path.CAST)
Pathological casts contain particle inclusions, such as RTECs (epithelial casts), granular components (granular casts), fat droplets (fatty casts), white blood cells (WBC casts), red blood cells (RBC casts) and others. Depending on the type of Path.CAST, these particles indicate pathological conditions of the kidney, including chronic kidney disease, acute nephritis, interstitial nephritis, glomerulonephritis, nephrotic syndrome, nephropathy and others.
