Which condition can cause reddish urine color?

Which condition can cause reddish urine color?

• A. Malignant melanoma
• B. Multiple myeloma
• C. Fanconi syndrome
• D. Muscular dystrophy

Answer: (D)

Reddish urine color is most often due to myoglobin in the urine from muscle breakdown (myoglobinuria). In muscular dystrophy, ongoing muscle degeneration can release myoglobin into the bloodstream and then into the urine, giving it a reddish or tea-colored appearance. This pigment-related change in urine color is a classic sign of pigmenturia from muscle injury, which is why muscular dystrophy best explains the finding. Malignant melanoma can produce dark urine from pigment like melanin in some cases, but that's not the typical cause of a reddish hue. Fanconi syndrome mainly affects tubular reabsorption and does not cause pigmenturia. Multiple myeloma affects urine via light chains and related changes rather than a distinctive reddish color.

Reddish urine color is most often due to myoglobin in the urine from muscle breakdown (myoglobinuria). In muscular dystrophy, ongoing muscle degeneration can release myoglobin into the bloodstream and then into the urine, giving it a reddish or tea-colored appearance. This pigment-related change in urine color is a classic sign of pigmenturia from muscle injury, which is why muscular dystrophy best explains the finding.

Malignant melanoma can produce dark urine from pigment like melanin in some cases, but that's not the typical cause of a reddish hue. Fanconi syndrome mainly affects tubular reabsorption and does not cause pigmenturia. Multiple myeloma affects urine via light chains and related changes rather than a distinctive reddish color.