January 2007: Acute scrotal pain needs prompt investigation
How can testicular pain be treated conservatively?
What causes post-vasectomy pain?
Which patients need specialist referral?
How can testicular pain be treated conservatively?
What causes post-vasectomy pain?
Which patients need specialist referral?
Scrotal pain has a variety of causes, which can lead to considerable morbidity and mortality if left undiagnosed. It is important to establish the aetiology to ensure appropriate investigation and management.
Causes of acute scrotal pain have been identified by various retrospective reviews in children: in a review of 238 cases, 16 per cent were caused by testicular torsion, 46 per cent by torsion of the testicular appendage and 35 per cent by epididymitis.1 Given the proportion of patients who have testicular torsion, early assessment of scrotal pain is critical.
A recent survey of urologists in Switzerland quoted a crude incidence of chronic scrotal pain syndrome as 350 to 450 cases per 100,000 men aged 25 to 85 years.2
Scrotal pain has been shown to be the presenting symptom for testicular cancer in 23.5 per cent of patients undergoing radical inguinal orchidectomy.3
The age-standardised rate for the incidence of testicular cancer in England and Wales in 1971 was 2.9 per 100,000, increasing to 5.4 per 100,000 in 1997.4 Pain can be the only symptom in patients who have clinically impalpable tumours.5
It is important when discussing this topic to separate acute and chronic testicular and scrotal pain.
Acute testicular pain
In patients presenting with acute testicular pain a history should be taken, and a physical examination of the abdomen and scrotum should be conducted.
At initial presentation the clinician should first exclude torsion of the spermatic cord. Features of this include sudden onset pain and an acutely tender testis on palpation. Classically, the testis is high riding and lies transversely.
Nausea and vomiting have been shown to have a positive predictive value of 96 per cent and 98 per cent respectively for spermatic cord torsion.6 Torsion can be difficult to assess, and so if it cannot be excluded or another diagnosis made, the patient should be seen by a specialist as an emergency referral.
The testicular appendages are pedunculated remnants of embryological structures that may also undergo torsion, causing acute scrotal pain. The appendix testis and appendix epididymis are located near each other, at the superior pole of the testis. Such pain may be difficult to differentiate from a true testicular torsion.
Other acute causes
Other causes of acute testicular pain include epididymitis and/or orchitis resulting from infection. These patients may have had preceding symptoms suggestive of a urinary tract infection (UTI) or sexually transmitted infection (STI). A dipstick urinalysis, or a urethral swab in the case of a suspected STI, is of value in confirming the diagnosis in these cases.
Incomplete bladder emptying may predispose patients to UTIs, and patients who present with epididymitis or orchitis secondary to a UTI need to have further evaluation to determine the cause of the infection. Patients with a suspected STI should ideally be referred to a genitourinary clinic for further evaluation.
If an infective aetiology is suspected then the patient can be treated with appropriate antibiotics, such as a four-week course of ciprofloxacin, with a course of doxycycline for a suspected STI.
Patients may present with referred pain caused by the passage of a lower ureteric calculus, and so all patients should have an abdominal examination and be asked about loin pain.
Acute scrotal pain can be caused by trauma; this is usually diagnosed from the history. These patients can develop substantial haematomas, which may become infected if left unchecked.
A less common cause of acute pain is Henoch-Schönlein purpura. This is a systemic vasculitis of childhood, and the hallmarks include a non-thrombocytopenic purpuric rash, abdominal pain and arthritis. Pain results from vasculitis of the scrotal blood vessels, which can result in inflammation and haemorrhage of the testis, spermatic cord, epididymis or scrotal wall.
More longstanding lesions within the scrotum can manifest with acute pain, for example hydroceles, epididymal cysts, varicoceles and testicular tumours. Diagnosis of these conditions is aided by careful examination of the patient, who may have presented because of scrotal swelling and discomfort. Diagnosis can be confirmed by ultrasound of the scrotum.
If a mass is felt in the scrotum, which cannot be felt as distinctly separate from the testis, then an urgent outpatient referral for suspected cancer should be made. In cases of suspected benign scrotal lesions, an ultrasound and urological referral should be organised.
Prostatitis may present as acute testicular pain, and may be also be associated with acute epididymitis.
Chronic testicular pain
Chronic testicular pain is a well recognised presenting symptom, but its pathophysiology is poorly understood and it can present a diagnostic and management challenge.
Chronic testicular pain has been defined as intermittent or constant testicular pain of at least three months duration, which significantly interferes with daily activities leading patients to seek medical attention.7 The terms chronic orchalgia or orchodynia may also be used.
Pain may be unilateral or bilateral. It may occur spontaneously or be exacerbated by physical activity. Discomfort may remain localised in the scrotum, or can radiate to the groin, perineum, back or legs.8
Causes of orchalgia include infection, tumour, varicocele, hydrocele, spermatocele, trauma, previous surgical interventions and, rarely, polyarteritis nodosa. Intermittent and severe pain can be caused by intermittent torsion of the spermatic cord.
Chronic orchalgia may also be caused by referred pain; the testis shares innervation with the caput and corpus portion of the epididymis, receiving its main innervation from the superior spermatic plexus via nerves accompanying the internal spermatic vessels. There are also neuronal contributions from the inferior spermatic plexus,
superior hypogastric plexus and other sympathetic chain ganglia. The parietal and visceral layers of the tunica vaginalis and the cremaster receive afferent innervation originating at L1-L2, carried by the genital branch of the genitofemoral nerve.9
Pain arising in the prostate, ureter, hip and intervertebral disc prolapse may result in referred scrotal discomfort. Entrapment of the ilioinguinal or genitofemoral nerve, often caused by inguinal hernias or their repair, may also be a cause.
Post-vasectomy pain may result from a sperm granuloma in the epididymis, or from the entrapment of nerve fibres in granulation tissue.10
The 10-year chronic pain rate in post-vasectomy patients was shown to be as high as 13.8 per cent in one recent study.11
It is recognised that psychological symptoms can also be present with chronic testicular pain. However, there have been no studies of the psychological aetiology in the development and continuation
of chronic testicular pain, although there is an association with chronic testicular pain and depression.12
A history should include questions regarding any lower urinary tract and bowel symptoms, as well as a genitourinary and sexual history. A previous history of trauma, urolithiasis, haematuria or haematospermia may be relevant.
The onset and nature of the pain can give important clues as to the diagnosis. For example, pain from groin or scrotal surgery is often continuous, and may be exacerbated by sexual intercourse.
A physical examination should include the entire genital area and the abdomen. Testicular examination should be conducted with the patient lying and then standing. Examination for hernia and a digital rectal examination (DRE) of the prostate should also be included. If referred pain is suspected then an examination of the back and hips may also be required.
Initial investigations should include a urinalysis to exclude a UTI causing epididymitis, orchitis or epididymo-orchitis. Urethral swabs may be appropriate if there is suggestion of an STI. Serum PSA should be checked, in conjunction with the DRE findings.
Previous studies have demonstrated that DRE causes an increase in total and free PSA levels.13,14 Total PSA can remain elevated for up to one week in most men, and the percentage of free PSA returns to pre-DRE biological variation of baseline levels in 90 per cent of men within 24 hours. Whenever possible, the PSA level should be checked prior to DRE.
The patient should always be counselled by their GP before having a PSA level checked. The possible causes of a raised PSA level (including prostate cancer) should be discussed, and the subsequent need for further investigation if the PSA remains elevated should be mentioned.
An ultrasound may be diagnostic for anatomical lesions. If the results of a physical examination and urinalysis are normal, then scrotal ultrasound has been shown to have little diagnostic value.15 However, in practice an ultrasound is nearly always requested, as it serves to reassure the clinician and patient and may help the patient in their perception of their symptoms. There are documented cases of impalpable testicular tumours detected only by ultrasound in patients with testicular discomfort.5
Investigation of the upper urinary tract with intravenous urography or ultrasonography may be appropriate if referred renal pain is suspected.
Cases of chronic epididymitis, orchitis or epididymo-orchitis can be treated with a course of antibiotics, such as a four-week course of ciprofloxacin 500mg?bd, with doxycycline if an STI is suspected. NSAIDs and scrotal support can be used in conjunction to improve symptoms.
A recent survey of urologists in?Switzerland found that antibiotics, most commonly quinolones (44 per cent) and tetracyclines (24 per cent), were given for a mean course of 20.5 days, with a range of five to 90 days, indicating a wide variation in practice.2
Although such initial first-line management is common, the recurrence rate of chronic scrotal pain after conservative treatment with antibiotics and NSAIDs is generally quite high.16 This may be attributable to an inappropriate choice of antibiotic treatment, or because infection is not the predominant causative factor.
Surgery is to be avoided if possible. However, in patients with pain associated with identifiable lesions confirmed on ultrasound, surgical management of intrascrotal lesions, by ligation of varicocele, hydrocele repair, spermatocelectomy, or orchidopexy for suspected intermittent torsion, can be highly effective.16
In patients who experience post-vasectomy pain, conservative measures may be used initially. If there is still no improvement, then exploration and vasovasostomy or vasoepididymostomy may provide a successful outcome.2 This, along with pain during ejaculation, suggests that obstruction or congestion of the vas deferens or the epididymis may be the cause of pain.
Assuming that no structural problems are found, cases of chronic testicular pain should be referred to a urologist after conservative measures have failed (NSAIDs and a course of antibiotics to treat possible chronic epididymitis and/or orchitis).
In cases with no identifiable or treatable cause, chronic pain team specialists can provide invaluable help for patients to gain symptomatic relief. Various combinations of analgesics, and sometimes the use of tricyclic antidepressants, can improve pain.
Transcutaneous electrical nerve stimulation (TENS) can be used.2 TENS causes the release of endorphins at the dorsal horn of the spinal cord. These, along with enkephalins, are the main transmitters responsible for closing the gate between the peripheral nerve and the spinal cord.
Spermatic cord blockade may be used with transrectal ultrasound guided injections of local anaesthetic into the region of the pelvic plexus.17
A multidisciplinary team approach, involving a urologist, pain clinic specialist and psychologist may be beneficial.
In patients who gain good, consistent symptomatic relief from a spermatic cord block with a local anaesthetic, as opposed to a placebo injection, microsurgical denervation of the spermatic cord, either as an open procedure or via a laparoscopic transperitoneal approach,18 can be considered. Microsurgical denervation can result in complete pain relief in up to 76 per cent of patients.19
In one study of 19 patients, epididymectomy was shown to be of benefit to 14 patients with chronic scrotal pain.20
Should the decision be made to perform an orchidectomy for intractable symptoms that have failed to respond to all other treatment, inguinal orchidectomy has been shown to be better than scrotal orchidectomy, the former providing 73 per cent pain relief compared with 55 per cent with the latter.7
These surgical measures should be considered a last resort.
Scrotal pain must first be differentiated as either acute or chronic in nature. In acute pain, it is important to identify and specifically treat the aetiology. In chronic scrotal pain, if a potential cause is found on examination or investigation, where possible it should be treated first.
Often, chronic scrotal pain does not have an easily identifiable aetiology and management can be difficult. Initially, conservative measures should be tried. If these treatments fail, the patient should be referred to a urologist for further evaluation and a multidisciplinary team approach should be used. Surgical intervention may be needed for cases of idiopathic chronic pain.Key points Authors
Mr Nimalan Arumainayagam
clinical research registrar in urology
Mr David Gillatt
MBChB ChM FRCS
consultant urologist, Southmead Hospital, Bristol