Differential Diagnosis for a 37-year-old Patient with Right Testicular Pain and Swelling

Single Most Likely Diagnosis

• Epididymitis: This is the most likely diagnosis given the symptoms of testicular pain and swelling. Epididymitis 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, which can be treated with antibiotics such as levoquin (levofloxacin).

Other Likely Diagnoses

• Orchitis: Inflammation of one or both testicles, usually caused by bacterial or viral infections. It can present with similar symptoms to epididymitis and may occur alongside it.
• Urinary Tract Infection (UTI): While the primary symptom is testicular pain and swelling, a UTI can cause referred pain to the testicles and is often associated with epididymitis, especially if the infection spreads.
• Testicular Torsion: Although less likely in a 37-year-old (it's more common in neonates and adolescents), it's a condition where the spermatic cord becomes twisted, cutting off the blood supply to the testicle. It requires emergency medical attention.

Do Not Miss Diagnoses

• Testicular Torsion: As mentioned, this is a medical emergency. Delayed diagnosis can result in loss of the testicle. It presents with sudden, severe testicular pain, often accompanied by nausea and vomiting.
• Testicular Cancer: Although rare, testicular cancer can present with a painless testicular mass. However, some patients may experience pain or discomfort. Given the potential severity of missing this diagnosis, it must be considered.
• Appendicitis: In rare cases, appendicitis can present with testicular pain if the inflamed appendix is located near the testicles (retrocecal appendix). This would be more likely if the patient also has abdominal pain.

Rare Diagnoses

• Henoch-Schönlein Purpura (HSP): A form of vasculitis that can affect the testicles, among other areas, causing pain and swelling. It's more common in children but can occur in adults.
• Spermatocele or Epididymal Cyst: These are benign cysts that can cause swelling but are usually painless. However, if they become large or infected, they could potentially cause pain.
• Varicocele: An enlargement of the veins within the scrotum, similar to varicose veins. It's usually painless but can cause a feeling of heaviness or discomfort.

Regarding the treatment with levoquin (levofloxacin), it is effective against bacterial epididymitis and UTIs, which are likely causes of the patient's symptoms. However, the choice of antibiotic should be guided by local resistance patterns and the results of any cultures obtained. Additionally, if the diagnosis of epididymitis is confirmed, sexual partners should be evaluated and treated if necessary, especially if the cause is a sexually transmitted infection like chlamydia or gonorrhea.