Chapter 111: Scrotal pain

Scrotal pain in males can occur in all age groups but the child or adolescent with acute scrotal pain often poses a diagnostic challenge. Serious problems include testicular torsion, strangulation of an inguinoscrotal hernia, a testicular tumour and a haematocele, all of which require surgical intervention.

History

It is important to determine whether there were any pre-existing predisposing factors or history of trauma.

• Have you noticed any burning of urine or penile discharge?

• Have you had an injury to your scrotal region such as being struck by a baseball, cricket ball or falling astride something?

• Have you travelled overseas recently?

• Have you been aware of a lump in your testicle or groin?

• Have you had an illness lately and have you noticed swelling of the glands in your neck or near your ear (i.e. screening for mumps)?

• Do you have back pain or have you injured your back?

Examination

Both sides of the scrotum must be examined and contrasted. Inguinal and femoral hernial orifices, the spermatic cord, testis and epididymis must be checked on both sides. The size, lie and elevation in the scrotum of the testis should be assessed, as should the cremasteric reflex. This is done by stroking or pinching the medial thigh, and considered positive if the testicle moves at least 0.5 cm. An absence of the ipsilateral cremasteric reflex is the most sensitive physical finding in testicular torsion but the reflex is often absent in small boys (under 2½ years) without torsion.²

The patient should be examined standing and supine. The scrotum and its contents are examined systematically starting with the skin, which may include sebaceous cysts or other dermatological conditions. A painful testis should be elevated gently to determine if the pain improves.

Investigations

Investigations that may help diagnose the painful testis in particular include:

• blood cell count

• urine analysis: microscopy and culture

• Chlamydia antigen detection tests

• ultrasound

• technetium-99m scan

This problem is more likely to be encountered in the adolescent, especially after the testis enlarges at puberty (13–16 year olds).¹ A list of causes is presented in TABLE 111.1. Infants, however, can also have torsion of a testis or a testicular appendage.

Clinical problem

A 15-year-old teenager presents with relatively acute onset of pain in his lower right abdomen and scrotum. He has vomited several times. On examination the right testicle is tender, red and swollen.

Discussion

The three main differential diagnoses of the acute scrotum in an adolescent are torsion of the testis, torsion of a testicular appendage and acute epididymo-orchitis (see FIG. 111.1). Less commonly the problem would be a haematoma or an acute hydrocele mimicking testicular torsion. This patient, however, must be regarded as having torsion of the testis until proven otherwise. Early operation with torsion is imperative because if the testis is deprived of its blood supply, infarction is inevitable and excision becomes necessary. Excluding mumps, no pre- or peripubertal youth should be diagnosed as suffering from acute epididymo-orchitis until the testis has been exposed at operation and torsion excluded.

Torsion of the testis

Torsion usually occurs because of an abnormally narrow anchoring of the testis by the testicular mesorchium posteriorly¹ and the tunica vaginalis (which normally covers only the testicle and epididymis) also covering the bottom end of the spermatic cord. This allows the testicle to have a more mobile and transverse lie, referred to as a ‘bell clapper deformity’, and makes it easier for the testicle to twist around upon its cord. This deformity is almost invariably present on the other testicle, so when surgical correction of the torted testis is done, orchidopexy should always be done on the other side also.

When a testicle torts, time is of the essence. One study suggests that the testicular salvage rate is 90% if detorsion occurs less than 6 hours after the onset of symptoms, but this drops to 50% after 12 hours and <10% after 24 hours.³

With torsion of the testicle there is pain of sudden onset, described as a severe, aching, sickening pain in the groin that may be accompanied by nausea and vomiting. With epididymo-orchitis the attack usually begins with malaise and fever and is often associated with a urinary infection. The testicle soon becomes swollen and acutely tender; however, elevation and support of the scrotum usually relieves pain in this condition (Prehn sign) while tending to increase it with a torsion. A comparison of the clinical presentations is given in TABLE 111.2.

Radiology as a diagnostic aid

Ultrasound, particularly colour Doppler, is useful in distinguishing a cystic scrotal lump (such as a hydrocele) from a solid tumour. Its use to distinguish between a torsion and epididymo-orchitis is controversial as it cannot reliably detect changes that are diagnostic of early torsion. Since the investigation can involve unnecessary delay in treatment it is generally not recommended. A technetium-99m scan can differentiate between the two conditions: in torsion the testis is avascular while it is hyperaemic in epididymo-orchitis.

At surgery the testicle is untwisted and if viable an orchidopexy is performed. A gangrenous testicle is removed (see FIG. 111.2).

Cautionary tales

Many testicles are lost because of inappropriate delays with referral for an ultrasound. The patient should be referred immediately to a surgeon or surgical centre. Teenage boys presenting with acute right iliac fossa pain, nausea and vomiting are sometimes misdiagnosed as having acute appendicitis.

Torsion of a testicular appendage

Torsion of one of the testicular appendages (most commonly the hydatid of Morgagni) accounts for 60% of cases of acute scrotal pain in children¹ (torsion of the testis accounts for 30%, and epididymo-orchitis, idiopathic and other causes comprise the remaining 10%). Vestigial remnants to the testis or the epididymis are present in 90% of the male population.¹ Torsion of a testicular appendage has a similar presentation to that of torsion of the testis but is less severe (see FIG. 111.1).

Torsion of a testicular appendage can be diagnosed by the appearance of a dark blue nodule at the upper pole of the testis called the ‘blue dot sign’(provided that it is not masked by an associated hydrocele).³ Surgical exploration may be needed to distinguish this from torsion of the testis.

SCROTAL PAIN AT VARIOUS AGES

Acute epididymo-orchitis

Apart from mumps, acute epididymo-orchitis is usually caused by sexually transmitted pathogens, notably Chlamydia trachomatis (in particular), Mycoplasma genitalium and Gonococcus, in sexually active young males and by urinary tract pathogens in older males. In older men, it usually follows urinary tract obstruction and infection or instrumentation of the lower genitourinary tract.

• Bed rest

• Elevation and support of the scrotum

• Analgesics

• Antibiotics⁴

Sexually active men should be treated empirically for chlamydial or gonorrhoeal infection:

• use ceftriaxone 500 mg (in 2 mL of 1% lignocaine) IM (or 500 mg IV) as a single dose

• plus

• azithromycin 1 g (o) as a single dose

• plus either

• another dose of 1 g azithromycin a week later, or doxycycline 100 mg bd for 14 days

Associated with urinary infection:

• trimethoprim 300 mg (o) daily (child 4 mg/kg) for 14 days

• or

• cephalexin 500 mg (child 12.5 mg/kg) (o) 12-hourly for 14 days

• or

• amoxycillin/clavulanate 500/125 mg (child 12.5/3.1 mg/kg) (o) 12-hourly for 14 days or (if resistance to above suspected or proven)

• norfloxacin 400 mg (child 10 mg/kg up to 400 mg) (o) 12-hourly for 14 days

If severe infection, administer parenteral gentamicin + ampicillin followed by norflaxin.⁵

Orchitis

Acute orchitis is invariably due to mumps and occurs during late adolescence. Mumps orchitis has become relatively rare with vaccination. It is usually unilateral (see FIG. 111.3) but may be bilateral.

Testicular tumours can occur at all ages but are more common in young men aged 20–30 years (teratoma) and 25–40 years (seminoma). Sometimes they can mimic an acute inflammatory swelling and present with acute pain. See CHAPTER 112.

It is possible that a supposed testicular torsion may be found to be a strangulated inguinoscrotal hernia, usually an indirect inguinal hernia extending into the scrotum. It can be detected by careful palpation of the base (neck) of the scrotum, feeling for a cough impulse and being unable to ‘get above’ the swelling.

A diffuse haematoma into the scrotum that causes no significant problems can follow surgery to the inguinal area, a blow to this area or a fracture of the pelvis. These conditions cause extravasation of blood distally. However, a haematocele of the tunica vaginalis can be either acute or an ‘old clotted haematocele’ following injury, such as a blow to the testis, or the drainage of a hydrocele. Sometimes it can arise spontaneously. All types of haematoceles require surgical exploration to exclude testicular rupture or a tumour.

Trauma to the scrotum may produce urethral injury and extravasation of urine into the scrotum. This problem requires urgent surgery.

Sebaceous cysts are common and may be infected and require drainage. Less commonly, idiopathic scrotal oedema can present, usually in boys aged 5–10 years. With this condition, scrotal swelling and mild redness and tenderness begin gradually and spread, often across the midline and also possibly beyond the scrotum. Palpation reveals normal, non-tender testes but torsion needs to be excluded in some instances of the swollen red scrotum. Idiopathic scrotal oedema is believed to be allergic in origin, either localised (e.g. insect bite) or globalised as part of urticaria. It sometimes results from exposure to cold water. There may be a tender enlarged draining inguinal lymph node near the external ring.¹ Treatment includes scrotal support, analgesics and antihistamines.

Pain can be referred to the scrotal region from ureteric colic and quite commonly from disorders of the thoracolumbar spine, notably a disc disruption at the T12–L1 level involving the L1 nerve root. The pain therefore may be referred or radicular. In elderly men, referred pain can arise (uncommonly) from a ruptured abdominal aortic aneurysm or acute aortic dissection.

• Any suspicion of torsion of the testis

• Sudden onset of acute scrotal pain at any age

• A history of recurrent transient testicular pain in a young man

• Presence of a tender testicular lump

• Presence of a haematocele surrounding the testis

Note: Referral should be urgent, given the critical importance of time in testicular survival.