A 26-year-old male with no PMH presented to the ED with complaints of swelling in his scrotum. The swelling had developed over the course of six days. He reported that the right side seemed more swollen than the left. He also reported that there was a crushing pain in his scrotum that was present constantly and improved with elevation of his scrotum. He reported that the pain was a 10/10 in severity. He denied fever or chills. He also denied dysuria, frequency, penile discharge, and trauma to the genitals.
Initial VS: BP 118/76, HR 107, RR 20, SpO2 100%, T 37.3°C (99.1°F)
Physical exam was significant for diffuse tenderness over both the testes, but the right was much more tender than the left. There was also tenderness bilaterally over the epididymides (yes, this is really the pleural form of epididymis). There was noted to be a mild amount swelling throughout the scrotum. There was no penile discharge present.
A work-up was initiated with a CBC, chemistry panel, UA, and urine testing for gonorrhea and chlamydia. The ED team taking care of the patient felt that this presentation seemed consistent with epididymitis and orchitis, however, they wanted to be certain nothing else was going on so they did a bedside testicular ultrasound.
Here is the first image of the testes seen side-by-side.
You can see that there is color Doppler flow present bilaterally making torsion unlikely.
Next, each testicle was examined individually. Here is the left side with color Doppler flow:
You can see that there is flow present. Venous and arterial waveforms were not recorded.
Here is the color Doppler flow of the right side (the more tender side):
What do you notice that looks different from the left? Note: the settings were not adjusted between sides.
This testicle looks angry! There is much more flow on the right side. This is what a hyperemic or hyperperfused testicle looks like. With a presentation such as this patient had, this appearance should make you think of orchitis.
Next views of the epididymides were obtained:
You can see that the epididymis with color Doppler also appears to be hyperemic. This is consistent with epididymitis. There were no color Doppler images recorded of the right, but we were told it looked similar to the left. You can also see that there is some hypoechoic fluid present bilaterally surrounding the epididymides.
This patient was treated for epididymo-orchitis with the presumed pathogen being either gonorrhea or chlamydia.
His culture came back positive for gonorrhea two days later.
Epididymitis, epididymo-orchitis, and orchitis are the most common causes of acute scrotal pain in adult males. Traditionally, diagnosis has been made based off of the physical exam. We feel that ultrasound can aid in making these diagnoses more accurately and confidently while ruling out other causes of testicular pain, such as, testicular torsion. Below you can find the ultrasound features that are most commonly encountered in epididymitis and epididymo-orchitis.
Ultrasound Features of Epididymitis and Epididymo-Orchitis:
- Hyperperfusion (hyperemia) of the epididymis
- Hyperperfusion of the testicle
- Reactive hydrocele
- Epididymal abscess
- Epididymal enlargement
- Testicular enlargement
We should mention that rarely, epididymo-orchitis can present with hypoperfusion of the testicle. This is a worse prognostic sign and can progress to testicular infarction.
The treatment of epididymitis and epididymo-orchitis is aimed at targeting the pathogen that is most likely present. In males <35-years-old, Gonorrhea and Chlamydia are the most common pathogens. In males >35-years-old, E.Coli, Pseudomonas, and Proteus are most common.
Bottom Line: Ultrasound can easily help aid in the diagnosis of epididymitis and epididymo-orchitis. We feel using color Doppler is one of the easiest ways to help assess for these diagnoses.
- Horstman WG, Middleton WD, Melson GL. Scrotal inflammatory disease: color Doppler US findings. Radiology. 1991;179(1):55-59.
- Pilatz A, Wagenlehner F, Bschleipfer T, et al. Acute epididymitis in ultrasound: results of a prospective study with baseline and follow-up investigations in 134 patients. Eur J Radiol. 2013;82(12):e762-768.