Differential Diagnosis for Testicular Pain in a 22-year-old Male

Single Most Likely Diagnosis

• Epididymitis: This is an inflammation of the epididymis, a tube at the back of the testicle that stores and carries sperm. It is often caused by a bacterial infection, commonly chlamydia or gonorrhea, which are prevalent in sexually active young men. The symptoms include pain in the testicle, swelling, and redness of the scrotum.

Other Likely Diagnoses

• Orchitis: Inflammation of one or both testicles, usually caused by bacterial or viral infections. It can be associated with epididymitis and shares similar risk factors.
• Testicular torsion: Although more common in neonates and adolescents, it can occur in young adults. It is characterized by sudden, severe testicular pain and is a medical emergency.
• Varicocele: An enlargement of the veins within the scrotum, similar to varicose veins. It can cause a dull ache or discomfort and is more common on the left side.

Do Not Miss Diagnoses

• Testicular Torsion: As mentioned, it's a medical emergency that requires immediate attention. Delayed treatment can result in loss of the testicle.
• Testicular Cancer: Although rare, it is the most common cancer in young men. Pain is not typically the first symptom, but it can occur, especially if the tumor has grown large enough to cause discomfort or if there is bleeding into the tumor.
• Appendicitis (with an atypical presentation): In rare cases, appendicitis can present with testicular pain if the inflamed appendix is located near the testicles, a condition known as "appendicitis in an atypical position."

Rare Diagnoses

• Henoch-Schönlein Purpura (HSP): A form of vasculitis that affects blood vessels and can cause testicular pain among other symptoms like purpura, joint pain, and gastrointestinal symptoms.
• Spermatocele: A cystic structure that forms at the head of the epididymis and can cause discomfort or pain, though it is usually painless.
• Idiopathic scrotal edema: A condition characterized by sudden onset of scrotal swelling and redness without an identifiable cause, which can be painful.

Each of these diagnoses has distinct characteristics and risk factors, and a thorough medical history, physical examination, and sometimes diagnostic tests are necessary to determine the cause of testicular pain in a young male.