Hydrocele
A hydrocele is a fluid-filled sac that forms around the testicle, causing swelling in the scrotum. It is usually painless and benign, although the swelling can become uncomfortable or concerning in appearance. Hydroceles can occur at any age—from birth to adulthood—and may develop after injury, infection, or inflammation, or they may arise without a clear cause.
What is it?
A hydrocele forms when fluid collects in the thin sheath that surrounds the testicle. In infants, this is often due to a connection between the abdomen and scrotum that hasn’t fully closed. In adults, hydroceles may arise from inflammation, prior infection, injury, or other underlying conditions affecting the testicle or epididymis.
Ultrasound is typically used to confirm the diagnosis and distinguish a hydrocele from other causes of scrotal swelling, such as hernias, varicoceles, or tumors. Imaging can also show whether the hydrocele is simple (just fluid) or contains debris or septations that may require closer evaluation.
Important to Know
Hydroceles are generally harmless and may resolve on their own, especially in infants. Large or persistent hydroceles may cause discomfort, difficulty with physical activity, or cosmetic concerns. In adults, identifying and treating any underlying cause—such as infection or trauma—may help prevent recurrence.
Red flag symptoms include sudden severe scrotal pain, fever, redness, nausea, or rapid enlargement of the scrotum. These may indicate infection, torsion, or other urgent conditions that require immediate medical evaluation.