Hydrocele

Hydrocele is an accumulation of serous fluid in a body cavity, most commonly occurring around the testicle. This condition, known as hydrocele testis, usually involves fluid collecting within the tunica vaginalis, a layer derived from the peritoneum. Hydroceles are prevalent in males and can resolve without treatment within the first year, provided there is no hernia. Although rare, hydroceles can also occur in females in the canal of Nuck.

Causes

Hydroceles can develop through various mechanisms:

• Excessive production of fluid within the sac.
• Defective absorption of fluid.
• Interference with lymphatic drainage, as seen in elephantiasis.
• Connection with a peritoneal hernia in congenital hydroceles.

Primary hydroceles can develop in adulthood, often due to impaired reabsorption of fluid. Secondary hydroceles can result from testicular diseases such as cancer, trauma, or orchitis.

Types of Hydroceles

Primary Hydroceles

Primary hydroceles are characterised by soft, non-tender swelling, often large in size. The presence of fluid can be demonstrated by transillumination. These hydroceles can grow significantly and cause atrophy of the testis due to compression or obstruction of blood supply. Ultrasound imaging is necessary to visualise the testis when the hydrocele sac is dense.

Secondary Hydroceles

Secondary hydroceles are associated with testicular diseases such as cancer, trauma, or epididymo-orchitis. These hydroceles are usually of moderate size, and the underlying testis is palpable. They typically subside when the primary condition is treated.

Infantile Hydroceles

Infantile hydroceles are due to a patent processus vaginalis (PPV) and occur in both infants and adults. There is no connection with the peritoneal cavity, and the hydrocele fluid may drain into the peritoneal cavity when lying down.

Congenital Hydroceles

Congenital hydroceles involve a patent processus vaginalis connecting with the peritoneal cavity. These hydroceles may occur bilaterally and can be associated with ascites or tuberculous peritonitis.

Encysted Hydrocele of the Cord

This type presents as a smooth, oval swelling near the spermatic cord, which can be mistaken for an inguinal hernia. It is also referred to as encysted hydrocele of the cord and transilluminates similarly to other hydroceles.

Signs and Symptoms

Hydroceles are usually painless and present as a swollen scrotum. They can be diagnosed through transillumination, where light passes through the fluid but not through a tumour. Secondary hydroceles may present with symptoms of the underlying condition, such as pain or swelling.

Diagnosis

Diagnosis of hydroceles involves physical examination and imaging techniques such as ultrasound. Primary hydroceles are identified by positive transillumination and fluctuation, absence of reducibility, and the inability to palpate the testis separately.

Complications

Complications of hydroceles include rupture, transformation into a haematocele, sac calcification, and testicular atrophy. Infection can lead to pyocele, and postherniorrhaphy hydroceles can occur after inguinal hernia repair.

Treatment

Most hydroceles in infants resolve without treatment within the first year. Persistent hydroceles or those occurring later in life require treatment if symptomatic. The preferred treatment is surgical excision of the hydrocele sac under anaesthesia. Aspiration with sclerotherapy is an alternative but often results in recurrence, making surgery the more definitive treatment.

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Self-assessment MCQs (single best answer)

What is a hydrocele?

Which layer is primarily involved in hydrocele testis?

How are primary hydroceles typically characterised?

What is the preferred diagnostic tool for visualising the testis in hydrocele cases?

Which type of hydrocele is associated with a patent processus vaginalis and can drain into the peritoneal cavity?

What common symptom is associated with hydrocele?

What is the preferred treatment for a symptomatic hydrocele in adults?

What potential complication can arise from an untreated hydrocele?

What is the primary cause of primary hydroceles in adults?

How can hydroceles be initially diagnosed non-invasively?