Introduction
Background
Acute epididymitis, testicular torsion, and testicular tumors can have a common presentation of pain. Acute epididymitis is the most common condition that causes acute scrotal pain. Distinguishing between acute epididymitis and testicular torsion is important because their treatments differ significantly.1,2
Transverse sonogram of the testis shows an enlarged and predominantly hypoechoic epididymis with a reactive hydrocele in a patient with acute epididymitis.
Color-flow sonogram shows increased vascularity in the epididymis. An enlarged epididymis with increased vascularity in the appropriate clinical setting is diagnostic of acute epididymitis.
Sonogram shows an enlarged epididymis with heterogeneous echotexture in a case of acute epididymitis.
CDC guidelines
According to the Centers for Disease Control and Prevention (CDC), the evaluation of men for epididymitis should include one of the following3 :
- Gram stain of urethral secretions demonstrating ≥5 WBC per oil immersion field. The Gram stain is the preferred rapid diagnostic test for evaluating urethritis. It is highly sensitive and specific for documenting both urethritis and the presence or absence of gonococcal infection. Gonococcal infection is established by documenting the presence of WBC containing intracellular gram-negative diplococci on urethral Gram stain.
- Positive leukocyte esterase test on first-void urine or microscopic examination of first-void urine sediment demonstrating ≥10 WBC per high-power field.
The CDC provides the following treatment guidelines for epididymitis3 :
- For acute epididymitis most likely caused by gonococcal or chlamydial infection: Ceftriaxone 250 mg IM in a single dose PLUS doxycycline 100 mg orally twice a day for 10 days.
- For acute epididymitis most likely caused by enteric organisms or for patients allergic to cephalosporins and/or tetracyclines: Ofloxacin 300 mg orally twice a day for 10 days OR levofloxacin 500 mg orally once daily for 10 days.
Recent studies
In a study by Tracy and Costabile, CDC guidelines for acute epididymitis were found to be followed in less than 35% of patients. They also noted that 97% of adult men were treated empirically with antibiotics often not in accordance with CDC guidelines. However, 50% of patients 18-35 years were prescribed an effective treatment according to CDC guidelines, as were 85% of patients older than 35 years.2
According to Karmazyn et al, children with epididymitis who have urinary tract abnormalities (UTAs) are more likely to have marked epididymal swelling, develop recurrent disease, and have a more protracted course. In 17 boys studied, the most common UTAs were hypospadias, neurogenic bladder, and functional bladder abnormality. Marked epididymal swelling occurred in 53% of children with UTAs, and epididymitis occurred in 53%. Chronic epididymitis, scrotal mass, and epididymal abscess occurred only in children with UTAs, when compared with controls.4
Pathophysiology
Usually, acute epididymitis is caused by Chlamydia trachomatis or Neisseria gonorrhoeae, which are sexually transmitted. In prepubertal boys and men older than 35 years, the disease is most frequently caused by Escherichia coli or Proteus mirabilis.
Other causes include tuberculosis (especially in patients with AIDS), sarcoidosis, brucellosis, and leprosy. Noninfectious causes include trauma and drugs such as amiodarone.
Mumps is the most common cause of orchitis and usually requires no intervention.
Frequency
United States
Acute epididymitis is the most common cause of acute scrotum in male adolescents.
International
As in the United States, acute epididymitis is the most common cause of acute scrotum in male adolescents.
Mortality/Morbidity
Complications of epididymitis and/or epididymo-orchitis include the following:
- Chronic epididymitis
- Infarction
- Infertility
- Abscess
- Atrophy
- Pyocele
Race
No racial predilection is reported.
Sex
Only males are affected.
Age
Adolescents and adults can be affected.
Anatomy
Normal testes develop in the celom and begin to descend into the scrotum at 36 weeks' gestation, guided by the contractile, cordlike structure called the gubernaculum testis. The epididymis and ductus deferens develop from the wolffian ducts.
At sonography, a normal adult testis has medium-level echoes and measures 5 x 3 x 2 cm. Septa extend from the tunica albuginea into the testicle, dividing the testes into lobules. The posterior surface of the tunica albuginea is reflected into the interior of the gland to form the incomplete septum known as the mediastinum of the testis. Each lobule is composed of many seminiferous tubules that open, via tubules (tubuli recti), into dilated spaces called the rete testes in the mediastinum. These, in turn, communicate via efferent ductules in the epididymal head.
The epididymis is composed of a head, body, and tail, the ducts of which continue as the vas deferens in the spermatic cord. The epididymis lies superior and lateral, along the posterior aspect of the testis; the head of epididymis is the most cephalic part.
Four testicular appendages have been described; however, only 2 are clinically relevant: the appendix of the testis (müllerian duct remnant) and the appendix of the epididymis, a wolffian duct remnant. Sonographically, the head of the epididymis is better depicted in the longitudinal view than in others. It is an isoechoic or slightly hypoechoic structure with medium-level echoes. Usually, the body of the epididymis is not identified at sonography in healthy adults. Sometimes, the epididymal tail is seen.
Presentation
Patients present with acute pain in the scrotum, which may be associated with fever and pyuria. Physical examination reveals an enlarged and tender epididymis that can be separated from the scrotum. The pain is relieved by elevating the scrotum to the symphysis pubis (Prehn sign). Usually, the cremasteric reflex is present.
Regarding the differential diagnosis, testicular torsion has a similar presentation. Torsion of the appendix of the testis also causes pain, but systemic symptoms are usually absent. Physical examination reveals the blue dot sign, which occurs in patients with torsion of the appendix of the testis. The Prehn sign is positive in patients with acute epididymitis and negative in patients with testicular torsion. The cremasteric reflex is present in patients with acute epididymitis and absent in patients with testicular torsion. Approximately 10% of the tumors may cause acute pain.
Preferred Examination
Sonography, clinical history taking, and physical examination are the mainstays in diagnosing acute epididymitis. The preferred imaging examination is ultrasonography, which is very useful in the detection of the epididymitis and/or epididymo-orchitis. Ultrasonography is helpful in excluding testicular torsion.5,6
Differential Diagnoses
Testicle, Malignant Tumors
Testicle, Trauma
Testicular Torsion
More on Epididymitis |
 Overview: Epididymitis |
| Imaging: Epididymitis |
| Follow-up: Epididymitis |
| Multimedia: Epididymitis |
| References |
| Further Reading |
| Next Page » |
References
Tracy CR, Steers WD, Costabile R. Diagnosis and management of epididymitis. Urol Clin North Am. Feb 2008;35(1):101-8; vii. [Medline].
Tracy CR, Costabile RA. The evaluation and treatment of acute epididymitis in a large university based population: are CDC guidelines being followed?. World J Urol. Apr 2009;27(2):259-63. [Medline].
Center for Disease Control and Prevention. Sexually Transmitted Diseases Treatment Guidelines 2006: Epididymitis. Centers for Disease Control and Prevention. Department of Health and Human Services. Available at http://www.cdc.gov/std/Treatment/2006/epididymitis.htm. Accessed November 6, 2009.
Karmazyn B, Kaefer M, Kauffman S, Jennings SG. Ultrasonography and clinical findings in children with epididymitis, with and without associated lower urinary tract abnormalities. Pediatr Radiol. Oct 2009;39(10):1054-8. [Medline].
Lee JC, Bhatt S, Dogra VS. Imaging of the epididymis. Ultrasound Q. Mar 2008;24(1):3-16. [Medline].
Al-Taheini KM, Pike J, Leonard M. Acute epididymitis in children: the role of radiologic studies. Urology. May 2008;71(5):826-9; discussion 829. [Medline].
Pearl MS, Hill MC. Ultrasound of the scrotum. Semin Ultrasound CT MR. Aug 2007;28(4):225-48. [Medline].
Bree RL, Hoang DT. Scrotal ultrasound. Radiol Clin North Am. Nov 1996;34(6):1183-205. [Medline].
Brown JM, Hammers LW, Barton JW. Quantitative Doppler assessment of acute scrotal inflammation. Radiology. Nov 1995;197(2):427-31. [Medline].
Burks DD, Markey BJ, Burkhard TK. Suspected testicular torsion and ischemia: evaluation with color Doppler sonography. Radiology. Jun 1990;175(3):815-21. [Medline].
Chou YH, Chan HK, Huang CN. [Torsion of the appendix testis]. Kaohsiung J Med Sci. Jun 1999;15(6):322-5. [Medline].
Dogra V, Bhatt S. Acute painful scrotum. Radiol Clin North Am. Mar 2004;42(2):349-63. [Medline].
Dogra VS, Gottlieb RH, Oka M. Sonography of the scrotum. Radiology. Apr 2003;227(1):18-36.
Dogra VS, Rubens DJ, Gottlieb RH. Torsion and beyond: new twists in spectral Doppler evaluation of the scrotum. J Ultrasound Med. Aug 2004;23(8):1077-85.
Dogra VS, Sessions A, Mevorach RA. Reversal of diastolic plateau in partial testicular torsion. J Clin Ultrasound. Feb 2001;29(2):105-8. [Medline].
Gordon LM, Stein SM, Ralls PW. Traumatic epididymitis: evaluation with color Doppler sonography. AJR Am J Roentgenol. Jun 1996;166(6):1323-5. [Medline].
Gronski M, Hollman AS. The acute paediatric scrotum: the role of colour doppler ultrasound. Eur J Radiol. Jan 1998;26(2):183-93. [Medline].
Hawtrey CE. Assessment of acute scrotal symptoms and findings. A clinician''s dilemma. Urol Clin North Am. Nov 1998;25(4):715-23, x. [Medline].
Herbener TE. Ultrasound in the assessment of the acute scrotum. J Clin Ultrasound. Oct 1996;24(8):405-21. [Medline].
Horstman WG. Scrotal imaging. Urol Clin North Am. Aug 1997;24(3):653-71. [Medline].
Lerner RM, Mevorach RA, Hulbert WC. Color Doppler US in the evaluation of acute scrotal disease. Radiology. Aug 1990;176(2):355-8. [Medline].
Mevorach RA, Lerner RM, Greenspan BS. Color Doppler ultrasound compared to a radionuclide scanning of spermatic cord torsion in a canine model. J Urol. Feb 1991;145(2):428-33. [Medline].
Noske HD, Kraus SW, Altinkilic BM. Historical milestones regarding torsion of the scrotal organs. J Urol. Jan 1998;159(1):13-6. [Medline].
Further Reading
Related eMedicine topics
Epididymitis (from Urology)
Epididymitis (from Emergency Medicine)
Testicular Torsion
Testicular Choriocarcinoma
Bedside Ultrasonography, Testicular Evaluation
Guidelines
Epididymitis and Orchitis. In: Guidelines on the Management of Urinary and Male Genital Tract Infections
ACR Appropriateness Criteria Acute Onset of Scrotal Pain (Without Trauma, Without Antecedent Mass)
Keywords
epididymitis, epididymis, acute epididymitis, epididymo-orchitis, acute scrotum, acute scrotal pain, testicular torsion, Chlamydia trachomatis, C trachomatis, Neisseria gonorrhoeae, N gonorrhoeae, Escherichia coli, E coli, Proteus mirabilis, P mirabilis, Prehn sign
