Myoglobinuria
Myoglobinuria is the presence of myoglobin in the urine, usually associated to rhabdomyolysis or muscle destruction. Myoglobin is present in muscle cells as a reserve of oxygen. Trauma, vascular problems, venoms, certain drugs and other situations can destroy or damage the muscle releasing myoglobin to the circulation and thus to the kidneys. Under ideal situations myoglobin will be filtered and excreted with the urine, but if too much myoglobin is released into the circulation or in case of renal problems, it can occlude the renal filtration system leading to acute tubular necrosis and acute renal insufficiency.