Which symptom is commonly associated with myoglobinuria?

Myoglobinuria is a condition characterized by the presence of myoglobin in the urine, often due to muscle injury or damage, such as in cases of rhabdomyolysis. The key symptom associated with myoglobinuria is dark urine, which results from the spilling of myoglobin into the bloodstream and then to the urine, where it can turn a dark brown or reddish color. This discoloration is a direct indicator of muscle breakdown and the subsequent release of myoglobin.

While severe pain in muscles can be a consequence of the underlying muscle injury that leads to myoglobinuria, it is not specific to this condition alone. Similarly, swelling in joints or fever and chills can occur due to various other musculoskeletal or systemic issues, but they are not hallmark signs of myoglobinuria. The distinctive symptom of dark urine effectively marks myoglobinuria and signifies the presence of myoglobin associated with muscle damage.