Differential Diagnosis for Dark Colored Urine
- Single most likely diagnosis
- Dehydration: This is the most common cause of dark-colored urine. When the body is not taking in enough fluids, the urine becomes more concentrated, leading to a darker color.
- Other Likely diagnoses
- Blood in the urine (Hematuria): The presence of blood in the urine can cause it to appear dark or tea-colored. This can be due to various reasons such as urinary tract infections, kidney stones, or bladder infections.
- Liver disease: Certain liver conditions, like cirrhosis or hepatitis, can cause changes in urine color due to the buildup of bilirubin, a yellow pigment that can turn urine dark.
- Medications: Certain medications, such as rifampicin (an antibiotic) or metronidazole (an antibiotic and antiprotozoal), can cause urine to turn dark or brown.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Rhabdomyolysis: A serious condition where muscle tissue breaks down, releasing myoglobin into the bloodstream, which can cause urine to turn dark brown or tea-colored. If left untreated, it can lead to kidney failure.
- Malignant melanoma: In rare cases, melanoma can cause urine to turn dark due to the presence of melanin. Although rare, it's crucial to consider this possibility to avoid delayed diagnosis.
- Rare diagnoses
- Alkaptonuria: A rare genetic disorder that affects the breakdown of certain amino acids, leading to the accumulation of homogentisic acid, which can cause urine to turn dark or black upon standing.
- Porphyria: A group of rare genetic disorders that can cause changes in urine color, including darkening, due to the accumulation of porphyrins.
- Blackwater fever: A rare complication of malaria, characterized by the presence of dark urine due to hemolysis (breakdown of red blood cells).