Testicular and scrotal conditions: Pathology review

Definitions & Key takeaways

The testicles and scrotum are part of the male reproductive system and can be affected by a variety of conditions. Common testicular and scrotal conditions include epididymitis, orchitis, testicular torsion, cryptorchidism, testicular tumor, varicocele, hydrocele, and spermatocele. Epididymitis refers to an inflammation of the epididymis usually caused by a bacterial infection. Orchitis occurs when there is an inflammation of one or both testicles. It is usually caused by mumps infection, but it can also be caused by bacterial infections, such as sexually transmitted infections. Next, there is testicular torsion, which occurs when the spermatic cord that provides blood to the testicle twists, cutting off the blood supply. There is also cryptorchidism, a common male birth defect that occurs when testicles fail to descend from the abdominal cavity into the scrotum, and often get stuck in the inguinal canal. Next come testicular tumors, which include tumors like germ cell type, such as seminoma. There is also varicocele, which is an enlargement of the veins in the scrotum, similar to varicose veins in the legs. Finally, we have hydrocele, which is a fluid-filled sac that develops in the scrotum, and spermatocele, which is a cyst that develops in the epididymis, usually containing dead sperm cells.

Chapters:

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Case Study0:00–0:59

In the middle of the night, a 16 year old male named Shane is brought to the emergency department by his parents after waking up with severe pain in his right scrotum.
Shane does not recall any traumatic events prior to the onset of his symptoms. On physical examination, the scrotum appears swollen; in addition, you notice that the pain is worsened with elevation of the scrotum, and stroking of the right inner thigh does not result in elevation of the right testis.
Later that day, you meet a 28 year old male called Elias, who comes in for a fertility evaluation. Elias and his wife have been trying to conceive for two years without success.
Recently, Elias has also noticed an enlargement and a feeling of pressure in his left scrotum. On physical examination, you palpate a mass along the spermatic cord that feels like a “bag of worms”.
Based on the initial presentation, both Shane and Elias seem to have some form of testicular and scrotal condition. Now, for your exams, remember that the testes begin their development in the abdominal cavity, within the peritoneum.

Pathology0:59–3:05

During the third trimester of pregnancy, the testes usually begin to descend into the pelvis via the inguinal canal, and ultimately settle in the scrotum.
This needs to occur because sperm can't survive at body temperature, and that’s a high yield fact! Now, as the testes gradually migrate, a peritoneal outpouching called the processus vaginalis forms, and pulls the layers of the anterolateral abdominal wall with it into the developing scrotum.
The testes then follow the processus vaginalis into the scrotum. After the testes have descended to the scrotum, the processus vaginalis closes up.
Within the scrotum, each testis remains partially covered by an extension of the peritoneum, which forms a serous layer called the tunica vaginalis.
The only part that’s not covered by the tunica vaginalis is where the testes are attached to the epididymis and spermatic cord.
Now, the epididymis is a coiled tube located at the back of the testicles, and moves the sperm from the testicles into the vas deferens, which in turn transports the sperm to the urethra.
On the other hand, the spermatic cord is the structure that contains the vas deferens, and also carries a network of arteries, veins, lymphatics, and nerves to the testicles.
All right, for your exams, some high yield testicular and scrotal conditions include epididymitis, orchitis, testicular torsion, cryptorchidism, varicocele, hydrocele, and spermatocele.Let’s start with epididymitis, which is an inflammation of the epididymis.

Epididymitis3:05–5:02

What’s important to remember is that in individuals younger than 35 years old, epididymitis is most commonly associated with sexually transmitted organisms, such as Chlamydia trachomatis and, less commonly, Neisseria gonorrhoeae.
On the other hand, in individuals older than 35 years, the most common organisms causing epididymitis are gram-negative bacteria, predominantly Escherichia coli, as well as Pseudomonas aeruginosa; and it’s often associated with urinary tract infections or benign prostatic hyperplasia.
Now, the main symptom of epididymitis is acute onset scrotal pain, which might also be accompanied by fevers, chills, and myalgias or muscle pain.
The diagnosis of epididymitis primarily relies on physical examination, revealing tenderness and swelling of the posterior side of the affected testicle.
For your exams, remember that a telltale sign of epididymitis is a positive Prehn sign, meaning that the pain is relieved when elevating the testicle.
In addition, individuals with epididymitis typically present with an intact cremasteric reflex, so lightly stroking or poking the superior and inner part of the thigh elicits a contraction of the cremaster muscle, causing the testis to elevate ipsilaterally.
To confirm the diagnosis, urinalysis, urine culture, and a urine nucleic acid amplification test for Neisseria gonorrhoeae and Chlamydia trachomatis should be performed.
Treatment includes antibiotics.Now, in some cases, epididymitis can spread to the testicle, resulting in epididymo-orchitis.

Orchitis5:02–5:44

Isolated orchitis, or inflammation of the testis, is rare; for your exams, remember that it is classically associated with mumps infection.
Symptoms of orchitis include acute onset scrotal pain, along with fever, nausea, and vomiting. For diagnosis, physical examination shows testicular swelling and tenderness, with a positive Prehn sign and normal cremasteric reflexes.
Treatment is mainly supportive.Now, another high yield cause of acute onset scrotal pain is testicular torsion. In fact, keep in mind that testicular torsion is one of the most common causes of acute scrotal pain among individuals between the ages of 12 and 18 years old.

Testicular torsion5:44–8:14

Now, testicular torsion occurs when the testes twist around the spermatic cord, basically cutting off its blood supply. This can happen either spontaneously or after trauma or vigorous physical activity.
Individuals typically present with acute and severe scrotal pain, often accompanied by nausea, vomiting, and diffuse lower abdominal pain.
Diagnosis of testicular torsion is mainly based on physical examination, where there’s a tender, enlarged, high-riding testis, with its long axis oriented transversely due to the shortening of the spermatic cord.
This is called a bell clapper deformity and it’s extremely high yield! Another characteristic finding of testicular torsion is a negative Prehn sign, so when elevating the scrotum, the pain isn’t relieved, and actually gets worse.
Another thing to bear in mind is that the cremasteric reflex is absent in testicular torsion, so stroking or poking the superior and inner part of the thigh does not result in elevation of the testis.
So, in a test question monitoring acute onset scrotal pain, watch out for these two findings, which should help you differentiate testicular torsion from epididymitis and orchitis.
Finally, diagnosis of testicular torsion can be confirmed with a doppler ultrasound. Treatment involves surgical correction by performing an orchidopexy, which is basically fixing the affected testicle into the afferent scrotum, and should be done within 6 hours from the onset of symptoms.
If the surgery cannot be performed within that time frame, a manual detorsion of the testicle can be done. Keep in mind that delayed treatment can cause testicular nonviability and infertility, in which case the surgical removal of the affected testicle, or an orchiectomy, is needed.
Our next condition is cryptorchidism, which is the most common birth defect in biological males. Cryptorchidism occurs when one or both of the testicles fail to descend into the scrotum, and often get stuck in the inguinal canal.

Cryptorchidism8:14–10:29

For your exams, note that this most commonly affects premature babies. Now, the real problem here is that the undescended testes will remain at body temperature, which impairs spermatogenesis, leading to fertility issues.
Now, high temperatures also affect Sertoli cells, which normally secrete testosterone in response to follicle stimulating hormone or FSH.
In contrast, high temperatures may not affect Leydig cells as much, so they’re able to secrete testosterone in response to luteinizing hormone or LH.
As a result, individuals with cryptorchidism can have normal levels of testosterone, especially when it’s unilateral, while testosterone levels are typically decreased in case of bilateral cryptorchidism.
And that’s very high yield! Now, to diagnose cryptorchidism, the undescended testes can usually be palpated outside of the scrotum.
If laboratory tests are performed, they’ll typically reveal increased levels of FSH and LH, and decreased inhibin B. Remember that testosterone levels will be only decreased in bilateral cryptorchidism, but will remain normal in unilateral cases.
Now, in most cases, treatment is not required, since cryptorchid testes tend to descend by the age of 6 months. If the testes don’t descend by the age of 2 years, treatment involves surgical repositioning with orchidopexy.
This should be performed before the second year of age to prevent the development of complications, including infertility, testicular torsion, and testicular tumors, especially of the germ cell type, such as seminoma.
Next, varicocele is characterized by dilation of the pampiniform plexus, which is a network of small veins that drain the testicles and is found within the spermatic cord.

Varicocele10:29–13:44

This occurs due to increased venous pressure, and venous stasis. For your test, remember that varicocele is more common on the left testis, since the left testicular vein drains into the left renal vein, forming a perpendicular angle before draining into the inferior vena cava, and this increases the resistance to blood flow.
In some cases, the left renal vein can be compressed between the aorta and superior mesenteric artery, causing a so-called nutcracker syndrome, which is rare but important to keep in mind for your exams!
On the other hand, the right testicular vein drains directly into the inferior vena cava, so there’s a shorter route and less resistance to blood flow.
As a result, varicocele rarely occurs on the right side. What’s extremely important to keep in mind is that right-sided varicocele should raise the suspicion of a retroperitoneal tumor, such as a renal cell carcinoma.
That’s because the tumor can promote the formation of thrombi that may obstruct the right testicular vein, or it can grow and invade the inferior vena cava, ultimately blocking the drainage of this side, and leading to varicocele.
Now, varicoceles typically present with a soft scrotal mass. In fact, they are the most common cause of scrotal enlargement in adults!
In some cases, varicocele may present with a feeling of pressure or dull, achy scrotal pain, and can even lead to infertility.
That’s because a major function of the testicular veins is to draw heat centrally in order to maintain the temperature of the testicles lower than the body temperature.
Impaired venous drainage can cause the testicular temperature to increase, ultimately affecting spermatogenesis. Diagnosis of varicocele is based on physical examination.
The key here is that the scrotal mass will feel like a “bag of worms” on palpation. In addition, the mass distends or gets bigger when the person is asked to cough or do the Valsalva maneuver, which is performed by exhaling forcefully against a closed upper airway, in order to increase abdominal pressure.
Also remember that in a transillumination test, which is performed by shining a light through the testicle, varicoceles don’t transilluminate.
Treatment of varicocele is indicated if the individual complains of pain or infertility, and may involve surgical ligation or embolization of the dilated pampiniform plexus.
Moving on, a hydrocele refers to fluid accumulation between the visceral and parietal layer of the tunica vaginalis of the testis.

Hydrocele13:44–15:58

This can occur on either side, and can be congenital or acquired. Congenital hydrocele is typically communicating, which happens when there’s a failure of the processus vaginalis to close up during development.
Remember that the processus vaginalis is an embryonic structure that precedes the descent of the testes from the abdomen into the scrotum, and then closes up.
In some cases, the processus vaginalis can remain open and allow for communication between the abdomen and the scrotum. This allows peritoneal fluid to move into the scrotum.
Fortunately, most cases of congenital hydrocele resolve spontaneously within the first year of age. On the other hand, acquired hydrocele is typically non-communicating, and most often occurs due to an underlying condition, such as trauma, tumor, or infections; the underlying infection examiners love the most is Wuchereria bancrofti, which is a type of roundworm that causes impaired lymphatic drainage.
Now, regardless of the type of hydrocele, individuals typically present with a soft, fluctuant, non-tender fullness in the scrotum.
Complications of a hydrocele include transformation into a hematocele, which is a collection of blood in the scrotum; as well as calcification and testicular atrophy.
For diagnosis of hydrocele, remember that in a transillumination test, the scrotum does transilluminate, and that’s a very important difference with varicocele!
In addition, an ultrasound can be performed to confirm the presence of an anechoic or echolucent mass around the testis.
Most cases of hydrocele resolve on their own and require no treatment, but those that don’t resolve need to be surgically repaired.
Finally, a spermatocele is a cystic mass arising from a dilation of the epididymis, rete testis, or efferent ductules, which often occurs due to an obstruction of the epididymal ducts.

Spermatocele15:58–17:11

Spermatoceles are thought to be caused by trauma, infection, or other inflammatory or autoimmune processes. For your exams, remember that spermatoceles are typically asymptomatic, but depending on the size, some individuals may develop pain.
Diagnosis is based on physical examination, where a soft, round mass can be palpated in the posterior and superior aspect of the testis.
Similar to hydroceles, the cystic nature of the mass allows for transillumination when shining a light through the testicle.
In addition, an ultrasound often reveals an anechoic or echolucent area with posterior acoustic enhancement. Most spermatoceles do not require treatment, unless it becomes symptomatic, in which case the mass can be removed surgically.
All right, as a quick recap… Testicular and scrotal conditions include epididymitis, which is an inflammation of the epididymis that presents with acute scrotal pain and is most often caused by sexually transmitted infections; as well as orchitis, which is an inflammation of the testes that’s most commonly caused by mumps infection.

Review 17:11–19:16

On physical examination, both conditions show testicular swelling and tenderness, as well as a positive Prehn sign, and normal cremasteric reflexes.
On the other hand, testicular torsion is the twisting of the testes around the spermatic cord and presents with acute scrotal pain, negative Prehn sign, absent cremasteric reflex, and needs immediate treatment within 6 hours.
Next, cryptorchidism is the abnormal or partial descent of the testes into the scrotum during embryological development, and complications include infertility, testicular torsion, and germ cell testicular tumors.
Varicocele is a dilation of the pampiniform plexus that most often happens on the left testicle; it typically presents as a scrotal enlargement that feels like a “bag of worms'' on palpation, and doesn’t transilluminate.
On the other hand, hydrocele refers to fluid accumulation between the two layers of the tunica vaginalis, and can be congenital, which is typically communicating, or acquired, which is most often non-communicating; it typically presents as a soft scrotal enlargement that transilluminates when shining a light behind the testicle.
Finally, spermatocele is a cystic mass that occurs due to dilation of the epididymal duct, and typically presents as an asymptomatic mass that transilluminates.Okay, back to our cases!

Summary 19:16–20:32

Shane is a 16 year old male that was brought to the emergency department with acute onset severe pain involving his right scrotum.
This, along with the swollen presentation, should make you think of epididymitis, orchitis, or testicular torsion. The key here is the negative Prehn sign, as well as the absence of a cremasteric reflex, which confirms that Shane is experiencing testicular torsion.
So, Shane should be referred for an immediate orchidopexy. On the other hand, Elias is a 28 year old male, who presents to the office for a fertility evaluation after two years of unsuccessful attempts to conceive a baby.
On top of that, Elias has recently been experiencing an enlargement and a feeling of pressure in his left scrotum. The final clue here is that, on palpation, the enlarged scrotum feels like a “bag of worms'', which makes this a typical case of varicocele.
And since Elias is complaining of fertility issues, he should be referred for surgical ligation