Differential Diagnosis for 39-year-old with Left Testicular Pain

Single Most Likely Diagnosis

• Epididymitis: This is the most common cause of acute testicular pain in adults, often resulting from bacterial infection. The patient's age and symptoms of testicular pain are consistent with this diagnosis.

Other Likely Diagnoses

• Orchitis: Inflammation of the testis, which can be caused by viral or bacterial infections. It often presents with testicular pain and swelling.
• Testicular Torsion: Although more common in younger males, testicular torsion can occur at any age and is a medical emergency. The patient's symptoms could be consistent with this diagnosis, especially if the pain is severe and acute.
• Varicocele: Enlargement of the veins within the scrotum, which can cause aching or discomfort in the testicle.

Do Not Miss Diagnoses

• Testicular Cancer: Although less common, testicular cancer can present with testicular pain or a palpable mass. It is crucial to perform a thorough physical examination and consider imaging studies to rule out this diagnosis.
• Appendicitis (with referred pain): In some cases, appendicitis can cause referred pain to the testicle, especially if the appendix is located near the testis.

Rare Diagnoses

• Spermatocele: A cystic structure filled with sperm, which can cause testicular pain or discomfort.
• Henoch-Schönlein Purpura (HSP): A systemic vasculitis that can cause testicular pain, swelling, and skin rash.
• Polyarteritis Nodosa (PAN): A systemic vasculitis that can cause testicular pain, swelling, and other systemic symptoms.

It is essential to conduct a thorough history, physical examination, and diagnostic workup, including laboratory tests and imaging studies (e.g., ultrasound), to determine the underlying cause of the patient's symptoms and develop an appropriate treatment plan.