children and older men. Men with epididymitis associ- ated with bacteriuria merit urologic evaluation. This may include imaging of the lower or upper urinary tract, or both. Additional studies such as cultures to diagnose bac- terial prostatitis, urine flow studies, or determination of residual urine volumes by ultrasound may be indicated by the clinical findings.
Imaging of the upper and lower urinary tract, usually starting with gray-scale ultrasound, is indicated in children who present with epididymitis. This population has a very high prevalence of anatomic congenital abnormali- ties, including many that merit consideration of surgical correction. This is the least common population of patients with epididymitis.
Berger RE, Alexander ER, Harnisch JP, et al. Etiology, manifesta- tions and therapy of acute epididymitis: Prospective study of 50 cases. J Urol1979;121:750–754. [PMID: 379366] (This article emphasizes the presentation of epididymitis in differ- ent age groups. For men older than 35 years,E. coli was the most important pathogen, whereas C trachomatisandN gon- orrhoeaewere the predominant pathogens in men younger than 35. )
Differential Diagnosis
The main considerations in the differential diagnosis of epididymitis include torsion of the testes and testicular tumor. The clinical history, physical examination, and results of imaging are important in distinguishing among these entities. An algorithm for the initial diag- nostic evaluation of the patient with the acute scrotum syndrome is presented in Figure 6–1. In general, in ado- lescents and adults, the initial evaluation will include microscopy and diagnostic testing for pathogens causing epididymitis. The history and physical examination determine whether other studies (eg, Doppler ultra- sound) are indicated to exclude conditions such as tes- ticular torsion or complications of epididymitis. In infants and prepubertal children, torsion of the testicle is a
EPIDIDYMITIS & THE ACUTE SCROTUM SYNDROME / 37 much more common cause of the acute scrotum syn-
drome than acute epididymitis or testicular cancer, and an acute scrotum in this group must be presumed to be torsion of the testicle unless proven otherwise.
A. TESTICULARTORSION
Acute epididymitis must always be differentiated from torsion of the testicle, which requires urgent surgical exploration to perform detorsion and orchidopexy to preserve testicular viability. A history of previous scrotal pain is more common in testicular torsion than in epi- didymitis, presumably reflecting previous intermittent torsion. A history of a sudden onset of scrotal pain is also more common in testicular torsion. A history of trauma to the testicle or lifting or straining at the onset of pain may occur with either epididymitis or torsion and is probably not significant in differentiating the eti- ology of the acute scrotum syndrome.
Unless physical examination is performed early in the course of the acute scrotum syndrome, findings may be very similar in torsion and epididymitis. In torsion, the testicle is often high in the scrotum (due to shorten- ing that occurs with twisting of the spermatic cord), whereas in epididymitis this is unusual. Also in torsion, examination of the involved testicle may reveal that the epididymis is anterior to the testis, rather than in the usual posterior orientation. In epididymitis, the sper- matic cord in the inguinal canal may be quite tender, whereas in torsion tenderness is generally limited to the scrotal contents.
Examination of the urine and urethral smear may prove helpful in differentiating epididymitis from torsion.
Patients with epididymitis usually have either urethral inflammation or bacteriuria or leukocytes in their urine, whereas in torsion these findings are usually absent.
Cases of suspected epididymitis in adolescents or young adults should be confirmed by Doppler ultra- sound or radionuclide scanning, because the incidence of torsion is also higher than the incidence of epi- didymitis for most populations in this age group. Doppler ultrasound may demonstrate increased blood flow to the acutely inflamed epididymis and decreased blood flow to a testicle that has undergone torsion, cutting off its blood supply. False-negative ultrasound findings can occur in some cases of testicular torsion (eg, hyperemia surrounding a necrotic testicle may produce a false- positive signal for epididymitis), and a strong clinical suspicion for torsion in the absence of consistent ultra- sound findings should prompt the clinician to consider surgical exploration. Radionuclide testicular scanning is another useful imaging modality that is also based on finding increased blood flow in epididymitis. Magnetic resonance imaging has also been reported in a few small studies to be accurate in differentiating among the causes of the acute scrotum syndrome. Thus, magnetic resonance merits further study.
In summary, multiple imaging modalities are avail- able to assist in distinguishing torsion from epididymi- tis. In all cases, unless the examiner and imaging can unequivocally rule out torsion of the testicle, scrotal exploration should be considered. (See Figure 6–2, which illustrates such a scenario.) Some experts believe surgical exploration without prior imaging is appropri- ate for presumed torsion, because after 4 hours of com- plete torsion, there is a significant risk of irreversible testicular damage.
Wilbert DM, Schaerfe CW, Stern WD, et al, Evaluation of the acute scrotum by color-coded Doppler ultrasonography. J Urol 1993;149:1475–1477. [PMID: 8501791] (This article con- firms earlier reports suggesting that color Doppler ultra- sonography is the preferred method for noninvasive imaging of arterial and venous blood vessels in patients with acute scrotal pain.)
B. TESTICULARTUMOR
Testicular tumor is another important consideration in the differential diagnosis of the acute scrotum syndrome.
The peak incidences for epididymitis and testicular tumors occur in similar age groups. The presentation of a painless or persistent testicular mass suggests the pos- sibility of testicular tumor. However, approximately one quarter of patients with testicular tumors present with testicular or scrotal pain. Therefore, the presence of tes- ticular or scrotal pain does not rule out a tumor, espe- cially because hemorrhage or rapid tumor growth may, on occasion, cause such pain.
Figure 6–2. Epididymitis in a 28-year-old man who underwent surgical exploration for a presumed testicular torsion. An inflamed tunica vaginalis and spermatic cord were present, along with an indurated, engorged epididymis (lower left). The testis and spermatic cord did not demonstrate findings consistent with testicular torsion. An aspiration culture of the epididymis grew Chlamydia trachomatis. This case illustrates the difficul- ties sometimes encountered in distinguishing acute epididymitis from testicular torsion.
38 / CHAPTER 6
In the early stages of epididymitis, swelling is limited to the epididymis, and differentiation from testicular tumor usually is not difficult. However, as epididymitis progresses and involvement of the testicle increases, the limits of inflammation are not easily defined. Further, testicular tumors may invade the epididymis and, on physical examination, mimic exactly the findings of acute epididymitis. Reactive hydrocele formation may further limit the usefulness of physical examination. In testicular tumors, the urine and urethral smear should show no evidence of inflammation.
Failure of improvement in the size of swelling or pain in any young man being treated for epididymitis should lead to the suspicion of an incorrect diagnosis or com- plication of epididymitis. Imaging, and possibly scrotal exploration through an inguinal incision, should be con- sidered to rule out carcinoma of the testicle. Transscrotal open or needle biopsy should never be performed when carcinoma of the testicle is suspected to avoid spreading the tumor to the inguinal lymph nodes, which are rarely involved by testicular tumors (the usual lymphatic drainage of the testis is to the nodes at the level of the renal hilum, not to the inguinal nodes).
C. COMMONINTRASCROTALCONDITIONS
Other common intrascrotal conditions included in the differential diagnosis of the acute scrotum include sper- matocele, hydrocele, varicocele, and hernia. Spermatocele andhydroceleare easily differentiated by transillumination or by ultrasound. The dilated scrotal veins characteristic of a varicoceledisappear on assuming the supine posi- tion and are accentuated by the Valsalva maneuver (straining). These appear as a “bag of worms” on physi- cal examination. A herniaprotruding into the scrotum may sometimes present difficulties in diagnosis. Usually, such a scrotal hernia is palpable as a mass protruding through the inguinal canal. Hernias may be reducible as the patient lies down or with pressure. Hernias are not transilluminable, and bowel sounds may occasionally be heard in the hernia contents.
Complications
An accurate diagnosis with early intervention may pre- vent long-term complications of epididymitis.
A. SURGICALCOMPLICATIONS
Since the availability of effective antimicrobial therapy, the incidence of surgical complications from epi- didymitis has decreased. The most serious local com- plications of epididymitis are abscess formation and infarction of the testicle, and both should be considered when a patient fails to improve clinically after 72 hours of appropriate antibiotic therapy, scrotal support, and bed rest. In many cases, abscess or testicular infarction may be identified by ultrasound or a radionuclide
scan. Treatment requires surgical drainage and, often, orchiectomy.
B. INFERTILITY
Another complication of acute epididymitis, although poorly documented, is decreased fertility. Infertility rates are high in patients with bilateral epididymitis and bilateral occlusion of the vas deferens or epididymis. In some cases of sexually transmitted epididymitis (eg, espe- cially with C trachomatisinfection), symptoms may be absent or minimal (ie, subclinical) and may lead to asymptomatic scarring and, possibly, decreased fertility.
This intriguing observation may be analogous to the well- documented finding that many infertile women with bilateral tubal obstruction have serologic evidence of past C trachomatisinfection, although only about half have a past history of salpingitis.
Because transit through the epididymis is necessary for development of normal sperm function, it is possible that acute inflammation and damage to the epididymis could lead to decreased fertility even in the absence of epididymal tubule occlusion. However, epididymal obstruction reverses spontaneously in some patients.
Whether unilateral epididymitis, subclinical epididymitis, or epididymitis without occlusion, can result in infertility remains unproven.
C. CHRONICEPIDIDYMITIS
Chronic epididymitis is a poorly defined clinical syn- drome. Patients labeled as having chronic epididymitis account for a significant number of outpatient urology visits. Until recently, there was no clear definition of this syndrome or its clinical course. A 2002 study by Nickel and colleagues began to address the unclear aspects of chronic epididymitis, starting with the clinical defini- tion. Based on the available literature, chronic epi- didymitis was defined as symptoms of discomfort or pain at least 3 months in duration in the scrotum, testicle, or epididymis localized to one or both epididymides on clinical examination. These investigators also performed a comprehensive clinical survey of 50 men meeting this definition and compared findings with a control group.
From their survey, a classification system for chronic epi- didymitis (inflammatory, obstructive, and epididymal- gia) and a symptom assessment index (based on pain and quality of life) were developed that may provide a basis for further epidemiologic and clinical studies.
It remains unclear whether chronic epididymitis is related to persistence of bacteria or bacterial antigens in the epididymis or whether this syndrome reflects an ongo- ing immunologic reaction, scarring, neurologic injury, or other factors. Chronic epididymitis is generally con- sidered idiopathic and traditionally felt to be unresponsive to antimicrobial therapy, which in some instances has lead to epididymectomy or other surgical procedures for pain relief. Our clinical experience includes numerous
EPIDIDYMITIS & THE ACUTE SCROTUM SYNDROME / 39 patients who have not responded to such surgical proce-
dures. Thus, our current approach to chronic epididymitis is to evaluate possible contributing anatomic and infec- tious causes. We then evaluate the response to anti- inflammatory therapy; spermatic cord blocks using local anaesthetics or steroids, or both; and other measures. To our knowledge, little evidence-based data are available to suggest that a substantial proportion of patients ben- efit from more invasive therapies.
Nickel JC, Siemens DR, Nickel KR, et al. The patient with chronic epididymitis: Characterization of an enigmatic syndrome.
J Urol2002;167:1701–1704. [PMID: 11912391] (This com- prehensive clinical survey of men diagnosed with chronic epi- didymitis defined and characterized this particular population, setting the stage for further studies in the etiology, epidemiol- ogy, and management of chronic epididymitis.)
Padmore DE, Norman RW, Millard OH. Analyses of indications for and outcomes of epididymectomy. J Urol1996;156:95–96.
[PMID: 8648848] (This report from a series of 57 patients who underwent epididymectomy found greater satisfaction among patients having excision of epididymal cysts (92%) than among patients with epididymitis or epididymalgia (43%,P<.001). Furthermore, more patients in the latter group complained of subsequent problems that they consid- ered related to the procedure. The authors conclude that epi- didymectomy should avoided for patients with epididymitis or epididymalgia unless they have been carefully counseled regarding the likelihood of poor results.)
Treatment
Effective management of epididymitis depends on accu- rate etiologic diagnosis. The responsible infectious causes must be identified and treated, and attention must be directed toward correction of any contributing anatomic, physiologic, and behavioral factors. The management of infectious epididymitis thus includes antimicrobial ther- apy directed against the most likely pathogens, com- bined with analgesics, scrotal support, and clinical follow-up (see Table 6–2).
A. ANTIMICROBIALTHERAPY
Because most cases of acute epididymitis are caused by infections, antimicrobial agents represent the corner- stone of therapy. Appropriate empiric therapy can be selected based on whether initial Gram stain evaluation of an endourethral specimen and urine microscopy sug- gest urethritis or bacteriuria as the inciting event.