Testicular or scrotal pain occurs when part or all of either one or both testicles hurt. Pain in the scrotum is also often included. Causes rank from benign muscular skeletal problems to emergency conditions such as Fournier's gangrene (an acute necrotic infection of the scrotum) and testicular torsion. The most common cause is epididymitis (a medical condition characterized by inflammation of the epididymis, a curved structure at the back of the testicle). 

Testicular pain may be either acute (a medical emergency demanding rapid diagnosis and treatment) or chronic (pain for greater than 3 months). 

The differential diagnosis of testicular pain is broad and involves conditions from benign to life-threatening. Scrotal pain, in both its acute and chronic forms, is a diagnostic challenge that must be carefully evaluated with a full patient history and physical examination. Pain, the dependent nature of the scrotum, and the edema and skin changes that accompany many scrotal pathologies may prevent a complete examination. The patient's age, sexual history, and duration, severity, and onset (gradual vs. sudden) of pain are necessary to focus the clinician's attention on the correct diagnostic path. In its acute form, scrotal pain is a medical emergency requiring prompt attention to rule out testicular torsion. The physical exam must include a careful evaluation of the abdomen and inguinal region and a genital exam to assess possible herniation.

Testicular pain is associated with several diseases including:

Epididymitis and Orchitis

Epididymitis occurs when there is inflammation of the epididymis. This condition usually presents with gradual onset of varying degrees of pain, and the scrotum may be red, warm and swollen. It is often accompanied by symptoms of a urinary tract infection, fever, and in over half of cases it presents in combination with orchitis. In those between the ages of 14 to 35 it is usually caused by either gonorrhea or chlamydia. In people either older or younger E. coli is the most common bacterial infection. Treatment involves the use of antibiotics.

Testicular cancer

Testicular cancer is a condition where the cells in the testis grow and divide abnormally and a tumour grows in the testis. The testicles are two glands found in the scrotum that produce sperm and hormones. Testicular cancer is typically painless.

Testicular cancer has a very good cure rate if it is found and treated early. It is important that young men check their testis each month for any lumps or swellings and, if concerned, should see their doctor straight away.

Varicocele

A varicocele is an abnormal dilation of the spermatic veins commonly due to an anatomical abnormality with an incidence of 10% to 20% in the general male population and 2% to 15% in adolescent males. The mechanism is thought to involve absent or malfunctioning vein valves, thus resulting in retrograde flow into the pampiniform plexus (a network of many small veins found in the human male spermatic cord) located in the spermatic cord and scrotum from the internal spermatic and cremasteric veins.

Varicocele pain typically presents as a dull, aching, and throbbing sensation in the scrotum without sharp or radiating components. It can be exacerbated by long periods of standing owing to the resultant increased hydrostatic pressure in the valveless veins of the pampiniform plexus. Careful physical examination of the scrotum and spermatic cord is required and the classic finding is a 'bag of worms' on palpation.

Varicoceles have been associated with male infertility, although the exact cause-and-effect relationships have not been established. Leading theories suggest that elevated scrotal temperature, hypoxia secondary to stasis, and reflux of renal and adrenal metabolites result in impaired spermatogenesis and infertility.

Mumps

Mumps is a viral disease caused by the mumps virus. Initial signs and symptoms often include fever, muscle pain, headache, and feeling tired. This is then usually followed by painful swelling of one or both parotid salivary glands. Symptoms typically occur 16 to 18 days after exposure and resolve after seven to ten days. Symptoms in adults are often more severe than in children. About a third of people have mild or no symptoms. Women may develop ovarian swelling but this does not increase the risk of infertility. In young men, mumps can cause inflammation and swelling in one or both testes.

Testicular torsion

Testicular torsion is the most common cause of acute scrotal pain in prepubertal and adolescent boys. Intermittent testicular torsion should be considered in all young males with a history of scrotal pain and swelling. It may be intravaginal or extravaginal. 

Intravaginal torsion occurs when the testicle can freely rotate within the tunica vaginalis (the pouch of serous membrane that covers the testes); this can be due to a congenital anomaly called the bell clapper deformity. This deformity is due to failure of posterior anchorage of the gubernaculum, epididymis, and testis, thus allowing the testis to freely rotate within the tunica vaginalis. 

Extravaginal torsion occurs when the testis rotates within the scrotum owing to inadequate fusion of the testicle to the scrotal wall or increased mobility. The torsion follows rotation of the spermatic cord and results in ischemia (a restriction in blood supply to tissues).

Prostatitis

Prostatitis (less commonly prostatosis) is inflammation of the prostate gland. Symptoms of prostatitis are vague and involve pain in the pelvic region, urethral symptoms, voiding dysfunction, sexual disorder, and possibly considerable psychosocial distress. Pain may also spread to your penis and testicles (testes). 

Prostatitis is classified into acute, chronic, asymptomatic inflammatory prostatitis, and chronic pelvic pain syndrome.The conditions are distinguished by the different presentation of pain, white blood cells (WBCs) in the urine, duration of symptoms and bacteria cultured from the urine.

Poor semen quality may be the most common cause of male infertility, and there is a general consensus that reduced fertility and poorer semen quality may be the result of male accessory gland infection.

Hydrocele testis

A hydrocele testis is an accumulation of clear fluid in the tunica vaginalis, the most internal of membranes containing a testicle. A primary hydrocele causes a painless enlargement in the scrotum on the affected side and is thought to be due to the defective absorption of fluid secreted between the two layers of the tunica vaginalis. A secondary hydrocele is secondary to either inflammation or a neoplasm in the testis.

A hydrocele usually occurs on one side, but can also affect both sides. The accumulation can be a marker of physical trauma, infection, tumor or varicocele surgery, but the cause is generally unknown. Indirect inguinal hernia indicates increased risk of hydrocele.

A hydrocele feels like a small fluid-filled balloon inside the scrotum. It is smooth, and is mainly in front of the testis. Hydroceles vary greatly in size and are typically painless and harmless. However, as the fluid continues to accumulate and the scrotum further enlarges, more discomfort can be expected. Large hydroceles will cause discomfort because of their size. Sometimes pain can be in both testicles as pressure from the enlarged area puts pressure against the unaffected area which can cause discomfort to the normal testicle. It has also been found to decrease a man's sex drive and makes him less active for fear of enlarging the mass. As the fluid of a hydrocele is transparent, light shone through the hydrocelic region will be visible from the other side. This phenomenon is called transillumination.

Symptoms of a hydrocele can easily be distinguished from testicular cancer, as a hydrocele is soft and fluid-filled, whereas testicular cancer feels hard and rough.
A hydrocele testis is not generally thought to affect fertility. However, it may be indicative of other factors that may affect fertility.

Find more about related issues

Sources

Mumps ―sourced from Wikipedia licensed under CC BY- SA 3.0
Hydrocele testis ―sourced from Wikipedia licensed under CC BY- SA 3.0
Prostatitis ―sourced from Wikipedia licensed under CC BY-SA 3.0
Orchitis ―sourced from Boundless licensed under CC BY- SA 4.0
Testicular Cancer ―sourced from Queensland Government licensed under CC BY 3.0 AU
Prostatitis ―sourced from Fertilitypedia licensed under CC BY-SA 4.0
Blue balls ―sourced from Wikipedia licensed under CC BY-SA 3.0
Fournier gangrene ―sourced from Wikipedia licensed under CC BY-SA 3.0
Testicular Cancer ―sourced from Boundless licensed under CC BY-SA 4.0
Testicular pain ―sourced from Wikipedia licensed under CC BY-SA 3.0
Scrotal pain: Evaluation and management ―by Gordhan and Sadeghi-Nejad licensed under CC BY-NC 3.0
Creative Commons License
Except where otherwise noted, content on this site is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License, involving multiple copyrights under different terms listed in the Sources section.