Differential Diagnosis for a 20-year-old Male with Difficulty Urinating

Single Most Likely Diagnosis

• Paruresis (Psychogenic Urinary Retention): This condition is characterized by the inability to urinate in the presence of others, often due to anxiety or psychological factors. The patient's history of initial difficulty urinating in front of people and the continuation of symptoms months later supports this diagnosis.

Other Likely Diagnoses

• Anxiety Disorder: Generalized anxiety or social anxiety could exacerbate or contribute to the patient's difficulty in urinating, especially in public or when under observation.
• Performance Anxiety: Similar to paruresis, but not limited to urination, this could be a broader issue affecting the patient in various situations where performance is required.
• Urinary Retention due to Pelvic Floor Dysfunction: Although less likely given the psychological onset, pelvic floor dysfunction could lead to difficulty urinating and might be considered if there are other symptoms such as pain or if the condition doesn't improve with psychological interventions.

Do Not Miss Diagnoses

• Neurogenic Bladder: Although less common, conditions affecting the nerves controlling the bladder (e.g., spinal cord injuries, multiple sclerosis) could lead to urinary retention. A thorough neurological examination and history are crucial to rule this out.
• Obstructive Uropathy: Conditions like benign prostatic hyperplasia (less common in young men), urethral stricture, or bladder neck obstruction could cause difficulty urinating. The negative UA makes an infectious cause less likely, but obstruction needs to be considered.
• Medication Side Effects: Certain medications, such as anticholinergics or decongestants, can cause urinary retention. A thorough medication history is essential.

Rare Diagnoses

• Diabetic Neuropathy: Although rare in a 20-year-old without a known history of diabetes, diabetic neuropathy can affect bladder function. This would be considered if there were other signs of diabetes or neuropathy.
• Multiple System Atrophy: A rare neurodegenerative disorder that can cause autonomic dysfunction, including urinary retention. Given the patient's age and presentation, this is highly unlikely but would be considered in consideration of a broad differential diagnosis.