Differential Diagnosis for Dark Brown Urine
Single Most Likely Diagnosis
- Dehydration: This is often the most common cause of dark brown urine, as it results from a concentrated urine output due to insufficient fluid intake or excessive fluid loss.
Other Likely Diagnoses
- Urinary Tract Infection (UTI): Bacterial infections can cause changes in urine color, including dark brown, due to the presence of blood, pus, or the bacteria themselves.
- Kidney Stones: Stones in the urinary tract can cause bleeding, leading to dark or brown urine.
- Liver Disease: Certain liver conditions, such as hepatitis or cirrhosis, can lead to changes in urine color due to the buildup of bilirubin.
Do Not Miss Diagnoses
- Rhabdomyolysis: A serious condition where muscle tissue breaks down, releasing myoglobin into the bloodstream, which can cause dark brown or tea-colored urine. Missing this diagnosis can lead to severe kidney damage.
- Hemolytic Anemia: Conditions that cause the breakdown of red blood cells can lead to the release of hemoglobin into the urine, resulting in a dark brown color. This is a critical diagnosis not to miss due to its potential for severe anemia and kidney damage.
Rare Diagnoses
- Alkaptonuria: A rare genetic disorder that affects the breakdown of certain amino acids, leading to the accumulation of homogentisic acid in the body, which can cause dark urine.
- Melanoma: In rare cases, metastatic melanoma can cause dark urine due to the release of melanin into the bloodstream.
- Porphyria: A group of rare genetic disorders that can cause changes in urine color, including dark brown, due to the accumulation of porphyrins.