Differential Diagnosis for Green Urine

• Single most likely diagnosis
  • Medication effect (e.g., methylene blue, indomethacin, or cimetidine): Certain medications are known to cause a change in urine color, including turning it green, due to their chemical properties or metabolites.
• Other Likely diagnoses
  • Urinary tract infection (UTI) with specific bacteria (e.g., Pseudomonas aeruginosa): Some bacteria can produce pigments that alter urine color.
  • Food or dye ingestion (e.g., asparagus, food coloring): Consuming certain foods or substances can temporarily change urine color.
  • Metabolic disorders (e.g., hyperbilirubinemia): Although less common, certain metabolic issues can lead to changes in urine color.
• Do Not Miss diagnoses
  • Sepsis or severe infection: While rare, in severe infections, especially those involving the urinary tract, the urine can become discolored, including turning green, due to the presence of bacteria or their byproducts.
  • Liver disease: Advanced liver disease can lead to changes in urine color due to the accumulation of bilirubin or other substances.
• Rare diagnoses
  • Porphyrias: A group of rare genetic disorders that can lead to the accumulation of porphyrins, which may cause urine to turn various colors, including green.
  • Melanosis: Although extremely rare, conditions affecting melanin production or metabolism could theoretically alter urine color.
  • Certain types of cancer: In rare instances, cancers affecting the urinary tract or liver could potentially cause changes in urine color, including green urine, due to the production of specific metabolites or pigments.