Differential Diagnosis for Scrotal Pain in a 17-year-old Male
Single most likely diagnosis
- Idiopathic scrotal pain: This condition is characterized by chronic or recurrent scrotal pain without any identifiable cause, which fits the patient's presentation of ongoing pain with negative UA and scrotal US. The fact that Toradol helps mildly and the pain is positional, with relief when laying flat, suggests a possible musculoskeletal or referred pain component.
Other Likely diagnoses
- Epididymitis or orchitis (atypical presentation): Although the UA is negative, some cases of epididymitis or orchitis might not present with typical urinary symptoms or findings. The mild response to Toradol could indicate some degree of inflammation.
- Scrotal wall or spermatic cord issues (e.g., spermatocele, hydrocele, or varicocele): These conditions could cause positional pain and might not always be detected by US, especially if they are small or not causing significant structural changes.
- Referred pain from lumbar or abdominal sources: Pain from the lower back or abdominal organs can sometimes be referred to the scrotum, and the positional relief could suggest this, especially if there's an underlying musculoskeletal issue.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
- Testicular torsion: Although the patient's pain is chronic and relieved by position, which is atypical for testicular torsion, this diagnosis must always be considered due to its emergency nature. Delayed diagnosis can result in loss of the testicle.
- Appendicitis with atypical presentation: In rare cases, appendicitis can present with testicular pain, especially if the appendix is retrocecal. The fact that pain is relieved by laying flat does not rule out appendicitis entirely.
- Intra-abdominal pathology (e.g., inguinal hernia, intestinal obstruction): Other intra-abdominal issues could potentially cause referred pain to the scrotum and are important not to miss due to their potential for serious complications.
Rare diagnoses
- Scrotal neuropathic pain: This could be due to nerve entrapment or damage, which might not show up on standard imaging and could explain the chronic nature of the pain and its response to pain medication.
- Henoch-Schönlein purpura (HSP): A systemic vasculitis that can cause scrotal pain among other symptoms. It's rare but should be considered in the differential, especially if other systemic symptoms are present.
- Scrotal or testicular tumors: Although very rare in this age group, testicular cancer or other tumors could cause chronic pain and should be considered if other diagnoses are ruled out.