Differential Diagnosis for a 29-year-old man with perineal pain, constipation, intermittent dysuria, and pelvic muscle tenderness

• Single most likely diagnosis:
  • Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS): This condition is characterized by chronic pain in the perineum, pelvic floor, or genitalia, often accompanied by urinary symptoms and pelvic muscle tenderness, which aligns with the patient's symptoms. The normal urinalysis also supports this diagnosis, as CP/CPPS does not typically cause urinary tract infections or other abnormalities that would be detected through urinalysis.
• Other Likely diagnoses:
  • Levator ani syndrome: This condition involves pain and tenderness in the levator ani muscle, which could explain the patient's perineal pain and pelvic muscle tenderness. Constipation can also be a contributing factor or symptom.
  • Anal fissure: Although more commonly associated with sharp pain during and after defecation, an anal fissure could contribute to perineal pain and constipation if the patient is avoiding bowel movements due to pain.
  • Proctalgia fugax: This condition involves fleeting pain in the anus or rectum, which could be a component of the patient's perineal pain, though it doesn't fully explain all symptoms.
• Do Not Miss diagnoses:
  • Testicular torsion (although less likely in a 29-year-old without acute onset of severe pain): This is a medical emergency that requires immediate attention. While the patient's symptoms do not strongly suggest testicular torsion, any possibility of this condition necessitates prompt evaluation.
  • Epididymitis or orchitis: Inflammation of the epididymis or testis could cause pain and might be accompanied by urinary symptoms, though typically, there would be more pronounced testicular pain and possibly abnormalities on urinalysis.
  • Rectal cancer: Although rare in young adults, rectal cancer could cause perineal pain, constipation, and pelvic muscle tenderness. It's essential to consider this possibility, especially if other diagnoses are ruled out.
• Rare diagnoses:
  • Pudendal neuralgia: This condition involves pain along the distribution of the pudendal nerve and could explain perineal pain and some urinary symptoms.
  • Coccydynia: Pain in the coccyx (tailbone) area could contribute to perineal pain, especially if the patient has a history of trauma to the area.
  • Pelvic inflammatory disease (PID): While more common in women, PID can occur in men and could cause pelvic pain and urinary symptoms, though it would typically be associated with other signs of infection.