What is commonly released into circulation during rhabdomyolysis?

In cases of rhabdomyolysis, myoglobin is commonly released into circulation due to the breakdown of muscle tissue. When muscle fibers are damaged, they release myoglobin, a protein that helps store oxygen in muscles, into the bloodstream. This can have significant implications for the kidneys, as myoglobin can lead to acute kidney injury if not adequately filtered out of the body. The presence of myoglobin in urine is often what clinicians look for when diagnosing rhabdomyolysis, as it can cause the urine to appear dark or "tea-colored."

The other substances mentioned, such as pus, serum albumin, and cholesterol, are not typically associated with rhabdomyolysis. Pus is indicative of infection or an inflammatory response rather than muscle tissue breakdown. Serum albumin is a protein found in blood plasma but does not directly relate to muscle damage. Cholesterol, while important for various body functions, does not play a role in rhabdomyolysis. Thus, myoglobin’s release is the key indicator of this condition.