Myoglobinuria overview

Myoglobinuria is the presence of myoglobin in the urine, usually associated with rhabdomyolysis or muscle destruction. Myoglobin (Mb or MB) is an iron- and oxygen-binding protein found in muscles. Myoglobin is present in muscle cells as a reserve of oxygen.In humans, myoglobin is only found in the bloodstream after muscle injury. It is an abnormal finding, and can be diagnostically relevant when found in blood. Myoglobin is the primary oxygen-carrying pigment of muscle tissues. High concentrations of myoglobin in muscle cells allow organisms to hold their breath for a longer period of time. Diving mammals such as whales and seals have muscles with particularly high abundance of myoglobin. Myoglobin is found in Type I muscle, Type II A and Type II B, but most texts consider myoglobin not to be found in smooth muscle.