A standard hydrocele, the kind most men are diagnosed with, does not interfere with urination. The fluid sits in a sac surrounding the testicle, well away from the urinary tract. But there are real exceptions. When a hydrocele grows unusually large, extends into the abdomen, or coexists with another condition like an inguinal hernia or infection, urinary symptoms can and do appear. Understanding the difference between a harmless fluid collection and a situation that warrants concern is worth the few minutes it takes to read through the scenarios.
Where the Fluid Actually Sits
A hydrocele forms when serous fluid accumulates between two thin layers of tissue called the tunica vaginalis, which wraps around the testicle and part of the spermatic cord.1PubMed. A Review of Classification, Diagnosis, and Management of Hydrocele Normally, this lining secretes and reabsorbs small amounts of fluid to keep the testicle lubricated. A hydrocele develops when that balance tips, with more fluid produced than absorbed, or with drainage blocked. The key anatomical point is that this sac is a closed compartment within the scrotum. It has no direct connection to the bladder, the urethra, or the ureters. That separation is why the vast majority of hydroceles cause scrotal swelling and heaviness but nothing related to urination.
The Giant Hydrocele and Buried Penis Problem
When a hydrocele remains small or moderate, it stays contained in the scrotum and the penis functions normally. A very large hydrocele, however, can change things. As the scrotum balloons outward, the surrounding skin stretches and engulfs the shaft of the penis, effectively burying it within scrotal tissue. Once the penis is buried, the urethral opening can become difficult to access or aim, and the surrounding tissue may compress or kink the urethra enough to obstruct urine flow.
A published case report describes a 65-year-old man who developed a completely buried penis alongside a large right-sided hydrocele and presented with urinary retention, meaning he could not empty his bladder at all.2PubMed Central. Gross Hydrocele With Completely Buried Penis This is an extreme scenario, not a typical one. Most hydroceles never reach the size required to bury the penis. But the case illustrates that sheer volume of scrotal fluid can eventually produce a genuine urinary obstruction if the condition is left untreated for years. In situations like this, the urinary problem resolves once the hydrocele is surgically drained or removed.
Abdominoscrotal Hydrocele and Pressure on the Urinary Tract
An abdominoscrotal hydrocele is a rarer variant in which the fluid collection extends upward from the scrotum through the inguinal canal and into the lower abdomen. This type creates a dumbbell-shaped mass with one component in the scrotum and another sitting inside the pelvis or abdomen. Because the abdominal component occupies space near the bladder, ureters, and kidneys, it can compress those structures in ways that an ordinary scrotal hydrocele never would.
A systematic review of abdominoscrotal hydroceles found that hydronephrosis, a backup of urine into the kidney caused by ureteral compression, is a relatively common complication of this variant. The obstruction is usually on one side, though bilateral kidney involvement has been documented even with a unilateral hydrocele, because the mass can compress both ureters at the pelvic brim. Ureteral displacement and direct bladder compression have also been reported.3African Journal of Urology. Abdominoscrotal hydrocele: A systematic review and proposed clinical grading The good news is that this compression is mechanical: once the hydrocele is removed, the urinary tract obstruction resolves.
Individual case reports reinforce the pattern. One described an unusually large abdominoscrotal hydrocele in a child that caused right-sided hydroureteronephrosis (swelling of both the ureter and kidney) from direct pressure.4PubMed. Unilateral hydroureteronephrosis caused by abdominoscrotal hydrocele Another documented a seven-month-old boy with bilateral abdominoscrotal hydroceles that produced bilateral hydronephrosis, meaning both kidneys were affected.5Anatolian Journal of General Medical Research. A Rare Case: Bilateral Hydronephrosis Due to Bilateral Abdominoscrotal Hydrocele in an Infant These cases are uncommon, but they matter because hydronephrosis, if missed, can damage kidney function over time. If you or your child has a hydrocele that visibly extends above the scrotum into the groin or abdomen, imaging to check the kidneys and ureters is a reasonable precaution.
When Urinary Symptoms Point to Something Else Entirely
Many men who notice a hydrocele also happen to have unrelated urinary symptoms like frequency, urgency, or a weak stream. The instinct is to blame the hydrocele, but most of the time these symptoms have a separate cause. In men over 50, an enlarged prostate is by far the most common explanation for changes in urination. The prostate wraps around the urethra just below the bladder, and as it grows, it can squeeze the urethra and make it harder to start or finish urinating. A hydrocele sitting down in the scrotum has no way to produce that kind of obstruction. The two conditions can coexist, but they are not connected.
Infections that cause or accompany hydroceles are a different story. Epididymitis, an inflammation of the coiled tube behind the testicle, sometimes produces a reactive hydrocele as the surrounding tissue becomes irritated. Epididymitis itself can cause painful or difficult urination, increased frequency, and urgency. So a man with a new hydrocele and sudden urinary symptoms may have an underlying infection driving both problems. The urinary symptoms in that case are from the infection, not the fluid collection.
Inguinal Hernias Mimicking Hydroceles
There is another condition that can look and feel a lot like a hydrocele but has a much more direct relationship with the urinary tract: an inguinal hernia involving the bladder. Inguinal hernias push abdominal contents into the groin, and in a small percentage of cases, part of the bladder wall gets dragged along. Bladder involvement occurs in roughly one to four percent of inguinal hernias, and in obese men between the ages of 50 and 70, the rate may reach about ten percent.6PubMed Central. Inguinoscrotal bladder hernias: report of a series and review of the literature
When part of the bladder herniates into the scrotum, urinary symptoms follow. The classic presentation involves needing to compress or lift the scrotum to finish urinating, sometimes called “two-stage voiding.” Frequency and incomplete emptying are also common. A hydrocele can complicate the picture because the scrotal swelling from fluid makes it difficult to feel whether a hernia is also present.7PubMed Central. Scrotal Herniation of Bladder If you have scrotal swelling alongside urinary symptoms, particularly if the swelling changes size with straining or lying down, the possibility of a hernia with bladder involvement is worth raising with your doctor. An ultrasound or CT scan can usually sort out whether you are dealing with a hydrocele, a hernia, or both.
Hydroceles Linked to Lymphatic Filariasis
In tropical and subtropical regions where lymphatic filariasis is endemic, hydroceles are one of the most common manifestations of the disease. Filarial worms damage the lymphatic vessels in the scrotum, leading to chronic fluid buildup that can become enormous over years. These hydroceles differ from the simple, idiopathic variety seen in temperate climates because the underlying lymphatic damage can affect broader areas, including structures connected to the urinary tract.
A study of urinalysis findings in a filariasis-endemic area reported notable urinary abnormalities among affected individuals, including blood in the urine in about 28 percent of cases, elevated leukocytes in about 22 percent, and proteinuria in roughly 11 percent. Among those with proteinuria, the average 24-hour protein loss was high, and lymphocytes were detected in the urine in over two-thirds of recorded cases.8BMC Research Notes. Chiluria in a lymphatic filariasis endemic area These urinary changes are caused by the systemic lymphatic disease rather than by the hydrocele itself, but from the patient’s perspective, the hydrocele and the urinary abnormalities arrive together and feel like one problem. The distinction matters for treatment: draining or removing the hydrocele addresses the scrotal swelling but does not fix the lymphatic damage causing the urinary findings.
Can Hydrocele Surgery Cause Urinary Problems?
Surgery to remove a hydrocele, called a hydrocelectomy, is a routine procedure. It does not involve the urinary tract directly. The surgeon makes an incision in the scrotum or groin, drains the fluid, and either removes or folds back the tunica vaginalis so fluid cannot reaccumulate. The bladder and urethra are not touched. For this reason, urinary complications from the surgery itself are rare.
That said, temporary urinary retention after the procedure is possible. Anesthesia, pain medication, and swelling in the groin area can all make it harder to urinate in the first day or two after surgery. For most men, this resolves quickly with simple measures like standing to void or, if needed, a brief catheterization. One unusual case in the literature describes a man who developed urinary retention a full week after hydrocele surgery performed under spinal anesthesia. He went on to develop what was ultimately diagnosed as Elsberg syndrome, a rare condition in which viral reactivation causes inflammation of the nerves controlling bladder and bowel function.9Canadian Journal of Anesthesia. Urinary retention occurring one week after spinal anesthesia That case is a medical curiosity rather than something to expect, but it underscores a general principle: if urinary retention develops days after any surgery, it deserves prompt medical attention rather than a wait-and-see approach.
Practical Guidance for Sorting Out Your Symptoms
If you have a hydrocele and also notice changes in how you urinate, the most productive step is figuring out whether the two are actually connected. A few features can help you and your doctor narrow things down:
- Size matters: A small to moderate hydrocele that stays within the scrotum is very unlikely to affect urination. If your hydrocele is large enough to bury the penis or extends visibly into the groin, the connection becomes more plausible.
- Timing matters: Urinary symptoms that appeared long before the hydrocele, or that fluctuate independently of scrotal swelling, probably have a separate cause. Symptoms that started around the same time as rapid hydrocele growth are worth investigating together.
- Pain matters: A painless hydrocele with painful urination suggests an infection like epididymitis or a urinary tract infection. A painless hydrocele with a painless weak stream in an older man points toward an enlarged prostate.
- Reducibility matters: If the scrotal swelling changes size when you lie down, strain, or press on it, you may have a hernia rather than (or in addition to) a hydrocele. Hernias that involve the bladder produce urinary symptoms that hydroceles typically do not.
An ultrasound of the scrotum is the standard first step for confirming a hydrocele and ruling out other pathology.1PubMed. A Review of Classification, Diagnosis, and Management of Hydrocele If there is any concern about the urinary tract being involved, imaging of the kidneys and bladder can be added. For the majority of men, the reassuring answer is that their hydrocele and their urinary symptoms are unrelated passengers in the same general neighborhood of the body.
Hydroceles in Children and Newborns
Hydroceles in infants are common, occurring in up to several percent of newborn boys. Most of these are communicating hydroceles, meaning the channel between the abdomen and scrotum has not fully closed, allowing peritoneal fluid to flow back and forth. The scrotal swelling often fluctuates in size throughout the day. These hydroceles almost never cause urinary problems, and the vast majority resolve on their own by age one or two as the channel seals shut.
The exception, as discussed earlier, is the abdominoscrotal variant, which can extend into the abdomen and press on developing urinary structures. In infants, this is especially concerning because their ureters and kidneys are smaller and more vulnerable to compression. Reported cases include kidney swelling severe enough to require surgical intervention.5Anatolian Journal of General Medical Research. A Rare Case: Bilateral Hydronephrosis Due to Bilateral Abdominoscrotal Hydrocele in an Infant Pediatricians generally monitor simple hydroceles with periodic exams rather than rushing to surgery. But if a hydrocele in a child grows rapidly, extends above the scrotum, or is accompanied by difficulty urinating or signs of infection, earlier intervention becomes the right call. A pediatric urologist can distinguish a straightforward communicating hydrocele from the rarer variants that need more attention.