Differential Diagnosis for Green Discharge from the Penis in Males

Single Most Likely Diagnosis

• Gonorrhea: This sexually transmitted infection (STI) is known for causing greenish or yellowish discharge from the penis. It's a common condition that fits the symptom description closely.

Other Likely Diagnoses

• Chlamydia: Another STI that can cause discharge, though it's often clear or white. However, in some cases, it might appear greenish, especially if there's a secondary infection.
• Urethritis: Inflammation of the urethra can cause discharge, which might be green if there's a bacterial infection. This condition can be caused by STIs or other factors.
• Prostatitis: Inflammation of the prostate gland can lead to discharge, which might be green in color, especially if there's a bacterial infection involved.

Do Not Miss Diagnoses

• Sepsis: Although rare, if the discharge is accompanied by systemic symptoms like fever, chills, and severe pain, sepsis could be a life-threatening condition that needs immediate attention.
• Epididymitis: Inflammation of the epididymis (the tube behind the testicle that stores and carries sperm) can cause discharge and is a serious condition that requires prompt treatment to prevent complications.

Rare Diagnoses

• Urethral Stricture: A narrowing of the urethra can cause urinary symptoms and possibly discharge, though green discharge would be an uncommon presentation.
• Penile Cancer: Though extremely rare, penile cancer can cause a variety of symptoms including unusual discharge. It's essential to rule out this condition, especially in high-risk individuals or those with persistent symptoms.
• Reiter's Syndrome (Reactive Arthritis): A form of arthritis that occurs as a reaction to a bacterial infection, often an STI, which can cause urethritis and subsequent discharge among other symptoms.