Acute scrotal pain and swelling in children have many causes; however, in most cases the emergency physician (EP) can determine the etiology by the history and physical examination and by considering the age of the patient. Scrotal swelling may be painful or painless. The most common diagnoses for an acute scrotum are testicular torsion, torsion of the appendix testis or epididymis, and epididymitis, but includes a number of other things as well (Table 86-1). In all cases, the possibility of a surgical emergency must be considered and the evaluation and management must proceed accordingly. Color Doppler ultrasound is the examination of choice for imaging scrotal pathology.

TESTICULAR TORSION

Testicular torsion has a bimodal incidence, with the first peak in the neonatal period and a second in adolescence, although can occur at any age.^1,2 Torsion of the testes is a urologic emergency and results in a significant amount of legal action against EPs for missed diagnosis. The EP must suspect this diagnosis in any child with complaint of scrotal pain or signs of scrotal swelling on physical examination.

The classic description of the anatomic abnormality associated with torsion is the “bell-clapper” deformity that is often bilateral and causes the testes to have a horizontal lie within the scrotal sac (Fig. 86-1). The abnormal testicular attachments to the tunica vaginalis allow the testis to twist, along with the spermatic cord and the testicular artery; the vascular supply is compromised and the testis will necrose. After 4 to 6 hours of continuous pain, the salvage rate is 96% but drops to 20% after 12 hours of pain, and below 10% at 24 hours.¹ Torsion may be intermittent and therefore the duration of symptoms may not necessarily predict the viability of the testis.

Testicular torsion usually presents with sudden onset of unrelenting, unilateral scrotal or testicular pain, commonly associated with vomiting and flank or abdominal pain.² There may be a history of scrotal trauma or recent diagnosis of epididymitis. Episodic pain suggests intermittent torsion, and bilateral torsion (concurrent or asynchronous) can occur. An undescended testis is 10 times more likely to torse than when fully descended, and presents with lower quadrant pain and a nonpalpable testicle. Karmazyn et al. showed that pain for less than 6 hours, absent/decreased cremasteric reflex, and presence of nausea/vomiting were highly suggestive of a diagnosis of testicular torsion. If none of these were present, none of the children had testicular torsion but if all three were present 87% of the children had torsion.³ No single sign or symptom can predict testicular torsion 100% of the time; however, a combination of signs and symptoms may assist the EP in determining the risk. Beni-Israel et al. demonstrated in 17 boys with testicular torsion that all of the children had at least one of the following risk factors: pain duration less than 24 hours, nausea and/or vomiting, high position of the testis, or abnormal cremasteric reflex. Although the odds for having testicular torsion in the absence of a normal cremasteric reflex was high (odds ratio [OR] 27.8, 95% confidence interval [CI] 7.5–100), the presence of the reflex did not rule out torsion.⁴

Physical examination often reveals a swollen, erythematous, and exquisitely tender hemiscrotum (Fig. 86-2). Classically, the testicle is high riding and lying horizontally within the scrotum.¹ The examination becomes more difficult with time as edema, erythema, and a reactive hydrocele may develop.¹ Tenderness of the affected testis is diffuse, and the cremasteric reflex is most often absent. Elevating the testis will cause further pain (Prehn’s sign) instead of the relief that can be seen in epididymitis; however, this cannot reliably include or exclude torsion.^5,6

Diagnostic Evaluation and Management

Prompt urologic consultation should not be delayed to obtain confirmatory tests when torsion is suspected. Urinalysis often is normal but may show pyuria or bacteriuria, suggesting alternative diagnoses such as urinary tract infection (UTI), epididymitis, or orchitis. It is important to recognize that these findings do not rule out torsion. Other studies such as complete blood count and chemistries may be requested preoperatively but rarely help the diagnosis. High-resolution ultrasound with color-flow Doppler rapidly provides information about testicular blood flow. Moreover, anatomic structure and relationships are displayed with ultrasound, and ultrasound findings may be predictive of testicular viability.⁷ Sensitivity of ultrasound for torsion is 90%, and specificity above 98% in experienced hands.⁶ Further diagnostic evaluation (such as MRI) is reserved for patients in whom the diagnosis is in question after a negative ultrasound test and classic signs of testicular torsion. Urology consultation should be obtained immediately in patients with classic signs and symptoms, regardless of results of imaging studies.

Rapid urologic consultation should be obtained early on all patients with suspected torsion, and prompt surgical exploration is indicated. The torsed testicle is untwisted and removed if nonviable, and bilateral orchiopexy is performed. Manual detorsion of the torsed testes may be attempted in the ED if urology is unavailable or will be delayed. Patients are sedated, and the testicle is detorsed by turning the testicle outward toward the thigh, like opening a book (Fig. 86-3). If this does not provide sudden relief, detorsion in the opposite direction may be attempted.⁶

TORSION OF THE APPENDIX TESTIS

Testicular appendices are common and may occur on the testicle (known as hydatid of Morgagni, most likely to torse), the spermatic cord, or the epididymis. Torsion of the appendix testis occurs most frequently in prepubertal boys, and is often difficult to distinguish from torsion of the spermatic cord.⁶

Clinical presentation of torsion of the appendix testis is usually less severe than in testicular torsion (Table 86-2). Systemic symptoms such as nausea and vomiting are uncommon, and the physical examination may reveal diffuse testicular enlargement and pain or only a focal tenderness in the upper pole of the testis. After torsion of the appendix testis occurs, local inflammation can make the diagnosis more challenging. One case series showed that in 119 males with acute scrotal pain, more than 50% had torsion of the appendix testis, while only about one-third had testicular torsion. A “blue-dot” sign is occasionally noted when the necrotic appendage casts a blue hue under the scrotal skin (Fig. 86-4).⁸

Diagnostic Evaluation and Management

Color Doppler ultrasonography (US) occasionally is diagnostic, but usually is normal or reveals increased flow to the testicle.⁶

Bed rest, urologic follow-up, and analgesia are recommended for torsion of the appendix testis. The condition is self-limited and complications are rare. Surgical intervention is indicated when testicular torsion cannot be reliably excluded.

EPIDIDYMITIS

Epididymitis occurs in approximately one-third of children who present to the ED with acute scrotal pain and is the most common misdiagnosis for testicular torsion. It is more common in adolescents than young children, and is rare in infants.

In adolescents, epididymitis is often caused by sexually transmitted diseases such as Neisseria gonorrhea and Chlamydia trachomatis. In children younger than 6 years, urinary tract anomalies may be present, and pathogens causing UTIs (such as Escherichia coli) are rare. Bacterial infections represent a small minority of cases overall, and epididymitis may be viral or occur after other infections (such as upper respiratory infections), or possibly as a chemical inflammation caused by reflux of sterile urine into the ejaculatory ducts.⁹

History should include the time course of the symptoms, any history of trauma, sexual activity, and urinary symptoms (dysuria, hematuria, etc.). The primary symptom is dull unilateral scrotal pain with swelling, often increasing over several days.⁶ Fever, vomiting, and urinary symptoms may be present, and with time the pain may become diffuse and radiate to the lower abdomen. Symptoms in young children may be vague, and infants may present with an incidental finding of scrotal swelling.

Physical examination reveals an erythematous, warm, swollen epididymis, testicle, and scrotum. Tenderness is localized to the superior aspect of the testicle, and the testicle itself should be nontender and have a normal lie. Patients usually have a normal cremasteric reflex, and Prehn’s sign (relief upon elevation of the scrotum) may be present. However, these signs are not reliable in distinguishing epididymitis from testicular torsion.

Diagnostic Evaluation and Management

Epididymitis is often difficult to distinguish from testicular torsion, and urologic consultation should be obtained when the cause of scrotal pain is unclear. Urinalysis may show signs of UTI, and a complete blood cell count may reveal an elevated white blood cell count with left shift; however, these tests are normal in many cases of epididymitis. Color Doppler US should be performed and will reveal normal or increased flow to the affected testis in epididymitis, although there may be a higher rate of indeterminate studies in infants and young children.