1 Strenuous exercise, such as running a marathon, can also cause blood in the urine. 2  White blood cells may be a sign of infection or kidney disease. 3  Casts. 4  Some types of kidney disease can cause plugs of material (called casts) to form in tiny tubes in the kidneys.
A loop of Henle can be found in one of the hundreds of thousands of nephrons contained within the kidneys. The loop of Henle dips down from the nephron into the medulla and then back into the cortex. The loop of Henle is part of a nephron, a tiny tube inside the kidneys that filters solutes. The loop of Henle allows the kidneys to maintain the correct balance of water in the body.
1 The glomerular (Bowman's) capsule and the proximal and distal convoluted tubules are located in the cortex. 2  The loop of Henle is located in the medulla. 3  Filtrate from the distal convoluted tubule is drained into collecting ducts, which plunge through the medulla to empty urine into the calyces.