Which urinalysis finding is most typical of rhabdomyolysis?

Which urinalysis finding is most typical of rhabdomyolysis?

• A. Hematuria with RBCs
• B. Proteinuria
• C. Myoglobinuria
• D. Bilirubinuria

Answer: (C)

Rhabdomyolysis causes muscle cell breakdown and release of myoglobin into the bloodstream, which is filtered by the kidneys into the urine. This produces myoglobinuria, the most typical urinalysis finding. On a dipstick, the urine may look blood-positive because myoglobin has heme-like properties, but microscopic exam will show few or no red blood cells, helping distinguish this from true hematuria. Proteinuria or bilirubinuria are less specific and don’t point to rhabdomyolysis.

Rhabdomyolysis causes muscle cell breakdown and release of myoglobin into the bloodstream, which is filtered by the kidneys into the urine. This produces myoglobinuria, the most typical urinalysis finding. On a dipstick, the urine may look blood-positive because myoglobin has heme-like properties, but microscopic exam will show few or no red blood cells, helping distinguish this from true hematuria. Proteinuria or bilirubinuria are less specific and don’t point to rhabdomyolysis.