Objectives: The purpose of this article is to educate nurse practitioners about scrotal inflammation. After reading this article, the nurse practitioner should be able to:
- Discuss the anatomy and physiology of the scrotum;
- Outline the physical assessment of the scrotal sac and its contents; and
- Discuss the etiology, assessment and treatment of common disorders associated with scrotal inflammation.
The scrotum is a cutaneous sac that houses the paired testis, epididymis and lower spermatic cord. A variety of disorders may cause inflammation, enlargement and pain in one or more aspects of the scrotal skin and its contents. This article reviews the anatomy of the scrotum and its contents and focuses on common, non-traumatic disorders associated with inflammation of the scrotum, testis, epididymitis or spermatic cord.
Scrotal Anatomy and its Contents
In adult men, the scrotum is a skin-covered sac extending below the pubic bone.1,2 The scrotal skin differs from surrounding integument. It is devoid of subcutaneous fat and its color differs subtly from adjacent perineal skin. In younger men, the scrotum contains transverse folds called rugae, while older men have smoother, often shiny scrotal skin. The scrotal integument is hair-bearing and contains abundant sebaceous glands. A median raphe (ridge) divides the scrotum into two hemispheres; each contains a testis, epididymis and lower spermatic cord.
A cross section of the scrotum reveals multiple subcutaneous tissue layers that surround and protect the scrotal contents. Immediately beneath the skin are the smooth muscle bundles of the dartos. Next is the three-layered spermatic fascia, which suspends the testes and form part of the scrotal wall. The external spermatic fascia is an extension of the external oblique fascia; it anchors the testis to the external ring. A middle layer contains fascia and the cremasteric muscle; it arises from the internal oblique muscle and fascia and attaches to the inguinal ligament and pubic tubercle. Finally, the internal cremasteric fascia arises from transversalis fascia. The tunica vaginalis lies immediately beneath the spermatic fascia; it is derived from peritoneal connective tissue and surrounds the paired testes. It anchors the testes to the scrotal wall at its posterolateral border and lower pole via a structure called the gubernaculum. Arteries and veins supplying the vascular needs of the anterior scrotum branch from the external pudendal vessels, while offshoots of the perineal vessels supply the posterior scrotum. Innervation arising from nerve roots at spinal level S3 reaches the scrotum via branches of the perineal nerves.
The spermatic cord contains the testicular vessels (arteries and veins), vas deferens and spermatic fascia. Its vascular origins are from the abdominal aorta, reflecting movement of the testis from an abdominal to scrotal position during embryogenesis.1,2
The testes are paired, oval-shaped organs lying in each hemisphere of the scrotum. The cross-sectional anatomy of the testis reveals multiple compartments containing seminiferous tubules, the functional unit of the organ, and adjacent interstitial tissue. The mature testis contains 600 to 1,200 seminiferous tubules that open into tubuli recti and, ultimately, the rete testis. The rete testis combines to form between six and 15 ductuli efferentes that open into the epididymis. The seminiferous tubules are responsible for spermiogenesis while the interstitial tissues house vascular and lymphatic vessels, as well as specialized cells that support spermiogenesis.
The epididymis is a cylindrical organ typically found at the posterolateral surface of the testis. It is approximately 5 cm long and divided into a head or globus major, body (corpus) and tail (globus minor). Cross-sectional anatomy reveals a single tortuous canal lined with cilia that maintain a slow forward motion of spermatozoon that migrate from the head to the tail of the epididymis as they mature into cells capable of fertilizing an ovum. At its termination (tail), the epididymis delivers spermatozoa into the vas deferens, which connects the epididymis and the ejaculatory duct.
Routine Assessment of the Scrotum
Scrotal assessment should be completed in a reasonably warm room using a systematic approach and after an adequate explanation of the procedure.3 Inspection begins with the perineal and scrotal skin. The scrotal skin is typically darker than adjacent perineal integument. In people with red hair, it may have a pink tone, but it should not have a bright or deep reddish color. Transverse rugation (wrinkles) of the scrotal skin are visible in younger adults, but they are less apparent or nearly absent in older men. The skin is hair-bearing and may contain sebaceous cysts or angiokeratomas. Angiokeratomas are 1 mm to 2 mm papular lesions that are dark purple, red or black.4,5 They result from increased pressure in the scrotal blood vessels and rarely require medical intervention, unless they cause bleeding.4-6
Palpation may be performed from multiple positions, depending on the purpose of the examination. When palpating for inguinal herniations, have the patient sit in an upright position and gently insert your finger into the inguinal canal to the level of the external ring. Ask the patient to cough to identify a direct or indirect herniation of the bowel. Ask the patient to hold the penis upward over the lower abdomen to assist with palpation of the testes. The testes should be rubbery smooth and non-tender on gentle palpation.
In the adult man, testicular volume varies from 15 mL to 20 mL and each testes should be at least 4 x 3 cm.2,7 More precise measurements may be obtained using an orchidometer. The epididymis is shaped like a "C" or comma, and is normally found on the posterolateral surface of the testis. Men who are taught testicular self-examination should be educated about the presence and shape of the epididymis to avoid confusing it with a mass.
After palpation, elicit the cremasteric reflex by gently stroking the inner aspect of the thigh with the handle of a reflex hammer or a similar, non-sharp object and observe for retraction (elevation) of the unilateral testis and hemiscrotum.
Transillumination of the scrotum is appropriate in select cases. For this exam, darken the room and shine a strong light source through the scrotal contents. A penlight is usually inadequate for transillumination; a light source for endoscopy or examination of the ears or eyes is preferred. In the normal scrotum, the scrotum readily transilluminates, revealing the presence of the testes. Visualization of an absence of a testis or edema of the scrotum suggests renal or hepatic diseases. In contrast, solid masses (such as a hernia or testicular tumor) do not transilluminate.
Inflammation or Enlargement
A variety of disorders may cause inflammation of the scrotum (see table). This article focuses on the more common causes of scrotal inflammation and enlargement.
Rashes or inflammation of the scrotal skin are typically caused by perineal dermatitis. This infection causes redness of the skin and superficial erosion, and usually occurs in men with urinary or fecal incontinence requiring use of absorptive pads or incontinence briefs.8 Most dermatologic disorders are self-limiting or respond to topical therapy in combination with management of the underlying urinary or fecal incontinence. However, more serious cutaneous infections, such as cellulitis or necrotizing fasciitis, may occur and these require prompt, aggressive management.9-12 Cellulitis of the scrotal skin is typically caused by a Staphylococcus or Streptococcus species, and occasionally by a gram-negative organism such as Pseudomonas. However, the most serious cutaneous infection of the scrotum is necrotizing fasciitis of the scrotum, referred to as Fournier's gangrene.10 Although it begins as a localized cellulitis, it ultimately involves the deep fascia, destroying skin, subcutaneous tissues and local blood vessels. Multiple bacteria are involved in necrotizing fasciitis; risk factors include alcoholism, disease, diabetes mellitus and HIV.12 The mortality rate is as high as 20% to 22%.11
Both cellulitis and Fournier's gangrene cause local inflammation with redness of the skin and warmth and tenderness to touch. Suspect Fournier's gangrene whenever a patient has been diagnosed with scrotal cellulitis that does not respond to antimicrobial therapy or has symptoms of systemic illness out of proportion to the objective findings. Fournier's gangrene causes severe pain that exceeds the anticipated magnitude based on inspection of the skin. This pain is usually localized to the scrotal, perineal, perianal or inguinal areas.13 As the disease progresses, the scrotum becomes edematous and black, or dark green patches appear as the necrosis and gangrene spread. Systemic illness, characterized by fever, ileus, delirium, shock and death, follow unless the infection is arrested rapidly.
Management of scrotal cellulitis centers on antibiotic therapy. Swab local purulent discharge and submit it for culture and sensitivity testing.14 Prescribe an oral antibiotic unless the patient has significant systemic illness and is unable to tolerate fluids. A broad-spectrum drug, such as a fluoroquinolone, should be administered empirically pending culture results. Teach the patient and family about the signs and symptoms of Fournier's disease, particularly when advanced HIV infection, diabetes mellitus or chronic alcoholism is present. Advise patients to return for follow-up care if symptoms persist or the infection progresses after 2 or 3 days of antibiotic therapy.
The patient with Fournier's gangrene may be critically ill and in need of immediate supportive care, including fluid replacement and vascular volume expansion with crystalloids, colloids or blood transfusion.10 He also may require mechanical ventilation, replacement of clotting factors or even dialysis. In addition to stabilization, you should urgently refer the patient with Fournier's gangrene to a urologist. Aggressive surgical debridement is considered first-line therapy since the infection is resistant to antibiotic therapy and can progress to shock and death in a matter of hours unless the fasciitis is arrested. In addition to surgery, hyperbaric oxygen therapy may be administered as an adjunct to surgical debridement, or as an alternative treatment in highly select cases where surgical risk is unacceptable.15 Hyperbaric oxygen therapy slows or arrests the progress of Fournier's gangrene by delivering oxygen to ischemic tissues and promoting anaerobic bacterial death. Although not curative, antibiotic therapy should be initiated and maintained after surgical debridement in an attempt to limit the spread of necrotizing fasciitis and prevent sepsis.
Other Common Causes
Orchitis refers to any inflammation of a testis; in the clinical setting, it occurs as an isolated disorder or in response to acute epididymitis.14 Isolated infection of the testis is typically viral. It usually presents as a complication of the mumps virus, particularly when the disease occurs in postpubertal men. Other causes of viral orchitis include infection with the Coxsackie virus and following immunizations for rubella and mumps.16-18 Orchitis is limited to the testes, but it causes damage to the seminiferous tubules and an increased risk for infertility.
Epididymitis is usually caused by bacterial infection.10 During its earliest stage, the inflammation is limited to the epididymis, but reactive hyperemia soon follows, resulting in inflammation and pain involving both the epididymis and testis. Nevertheless, the bacterial infection does not normally spread to the testis. Epididymitis may be sexually transmitted or associated with urinary tract infection. Common pathogens include N. gonorrhea and C. trachomatis in heterosexual men and enteric bacterial species in homosexual men. Surgery or congenital anomalies that create urinary reflux into the vas deferens increase the risk for epididymitis.10,19
Spermatic cord torsion, often called testicular torsion, occurs when the spermatic cord is twisted, resulting in ischemia and tissue damage of the testis and epididymis.9 Torsion occurs suddenly, and testicular pain often occurs acutely or may awaken the patient from sleep. Some cases are associated with scrotal trauma or vigorous physical activity, but most cases are idiopathic.9,20 The majority of torsion occurs in children or adolescents, but it is not uncommon in adult men and leads to testicular infarction and organ death unless it is corrected within 4 to 20 hours of the original insult.21
Orchitis, epididymitis and spermatic torsion typically cause inflammation, pain and enlargement of the scrotum.10 The onset of symptoms is acute, and patients with torsion in particular may be able to discreetly pinpoint the onset of pain. Palpation of early epididymitis may reveal discrete inflammation and pain localized to the testis, but this later progresses to inflammation of the affected testis or an inflammatory hydrocele with swelling and tenderness of one or both hemiscrotum. Palpation of the patient with orchitis reveals inflammation of the testis and sparing of the epididymis, although patients usually report generalized tenderness affecting one or both hemiscrotum. Palpation of the patient with torsion of the spermatic cord reveals a testis that is located high in the hemiscrotum. The cremasteric reflex is typically absent, but it may be present during the early stages of torsion. Spermatic torsion also tends to cause swelling of the affected testis, but as much as 10% of cases present as tenderness without apparent edema.22
Signs and symptoms of systemic illness, including fever, chills and abdominal pain, occur in severe cases of orchitis or epididymitis. Lower abdominal pain and nausea frequently occur in spermatic torsion, but bothersome lower urinary tract symptoms or fever are absent.
Diagnostic imaging is essential for the differential diagnosis of spermatic cord torsion vs. epididymitis.23 A Doppler-enhanced ultrasound or radionuclide study can differentiate the ischemia characteristic of torsion from the hyperemia seen with epididymitis.24 The choice of examination is based on several considerations, including the availability of equipment and technical expertise needed to complete and interpret results of these imaging studies. These studies are obtained within the context of a urologic consultation.
Orchitis is a viral infection, and management focuses on alleviation of testicular pain, inflammation and fever. Local pain is managed by bed rest and use of a Bellevue Bridge (scrotal support with a soft cloth placed across the thighs to elevate the scrotum and promote venous and lymphatic drainage). Prescribe an NSAID to alleviate pain and inflammation and reduce fever, but an opioid analgesic may be required initially if scrotal pain is severe.25 Because bacterial infection cannot always be excluded, consider prescribing a broad-spectrum antibiotic until the associated fever and swelling subside, usually within 7 to 10 days. In severe cases, a short hospital stay may be necessary until the initial fever subsides and the patient is able to tolerate oral fluids. Counseling is needed after treatment, focusing on the increased risk of infertility following viral orchitis.
The management of epididymitis is influenced by the man's age, associated symptoms, and history of sexual activity.26 Among men who are not sexually active, collect a midstream urine specimen to identify the causative pathogen. Sexually active men must undergo screening for Chlamydia trachomatis and N. gonorrhea via a urethral swab, particularly if purulent or clear urethral discharge is present. Antibiotic therapy is initially empiric. Doxycycline or ceftriaxone may be prescribed when you suspect a sexually transmitted pathogen, and a fluoroquinolone such as ciprofloxacin is appropriate when epididymitis is associated with bacteriuria.26,27 The antibiotic may be changed based on the results of culture and sensitivity, and treatment should be continued for 7 to 10 days. Inflammation and pain are managed by bed rest, scrotal elevation using a Bellevue Bridge and an opioid analgesic or NSAID.
Spermatic cord torsion is a medical emergency that requires urgent surgical intervention. The primary goal of nurse practitioner management is to ensure an accurate diagnosis and surgical exploration (if indicated) as soon as possible.
Mikel Gray is a nurse practitioner with a PhD who specializes in urology at the University of Virginia in Charlottesville. He is also a professor in the university's Department of Urology and School of Nursing.