Overview

A hydrocele is an accumulation of fluid within the tunica vaginalis, a membrane that covers the testis and epididymis. They can occur in isolation or may be the first sign noticed of more sinister underlying pathology (e.g. malignancy).

Definitions 

Communicating hydroceles occur due to the failure of the closure of the processus vaginalis which allows peritoneal fluid to flow (communicate) into the scrotum:

  • This is seen in up to 94% of neonates and 20% of adults

Non-communicating hydroceles occur due to an imbalance of fluid secretion and reabsorption in the tunica vaginalis. This can occur secondary to trauma, testicular torsion, epididymo-orchitis, or following testicular surgery.

The term ‘simple hydroceles’ sometimes describes the congenital accumulation of fluid within the tunica vaginalis in male neonates. These usually resolve within the first 1-2 years of life spontaneously.

Epidemiology

  • Congenital scrotal hydroceles are clinically apparent in up to 5% of neonates
  • In adolescents and men, causes are due to infection, torsion, trauma, or testicular tumours

Causes

  • Communicating hydroceles are caused by a patent processus vaginalis
  • The causes of non-communicating hydroceles may include:
    • Testicular trauma
    • Testicular torsion
    • Testicular cancer
    • Infection (e.g. epididymo-orchitis)
    • Testicular surgery

Presentation

Overview

Features of a hydrocele include:

  • Unilateral, non-tender scrotal swelling:
    • Usually anterior and below the testis
    • Pain may be present due to an underlying cause or infection of the hydrocele
  • The swelling:
    • Is confined to the scrotum:
      • You can ‘get above’ the swelling
    • Transilluminates:
      • This is not specific, as some tumours can transilluminate as well
  • The testis is palpable:
    • This may difficult if the hydrocele is large

Investigations

Overview

The diagnosis may be clinical, however, an urgent ultrasound scan is required if any of the following apply:

  • There is any diagnostic doubt
  • There is suspicion of an underlying cause
  • The underlying testis cannot be palpated
  • There is tenderness on palpation
  • Transillumination shows internal shadows (suggesting material other than fluid in the hydrocele, such a tumour).

Differential Diagnoses

See Groin and Scrotal Lumps.

Management

In adults

Management depends on the severity and suspected underlying cause. If not already done, an ultrasound scan may be needed to exclude other causes (e.g. tumours).

If no underlying cause is suspected, reassurance is sufficient. If the hydrocele is large and symptomatic, refer to a urologist.

Congenital hydroceles

Congenital hydroceles usually resolve spontaneously by 12 months of age, therefore reassurance and monitoring is sufficient in most cases.

A referral for surgery is made if:

  • The hydrocele is still present after 12 months
  • The hydrocele is not decreasing in size
  • Concomitant inguinal hernia or underlying testicular pathology is suspected
  • A palpable abdominal mass is present (this suggests an abdomino-scrotal hydrocele)

Prognosis

  • The prognosis depends on the underlying cause
  • Most congenital hydroceles resolve spontaneously by 12 months
  • Recurrence after surgery is uncommon, but more likely if the initial hydrocele was large

Author