AUTHOR AND EDITOR INFORMATION

Section 1 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

INTRODUCTION

Section 2 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Background

A hydrocele is a collection of fluid within the processus vaginalis (PV), and it produces a swelling in the inguinal region or scrotum. An inguinal hernia occurs when abdominal organs protrude into the inguinal canal or scrotum. Inguinal hernia and hydrocele share a similar etiology and pathophysiology and may coexist.

In the healthy neonate after birth, the testicle is surrounded by a closed cavity, which is the tunica vaginalis (TV) of the scrotum. In postnatal life, this is a potential space that should not communicate with the peritoneum.

Pathophysiology

During fetal development, the testicle is located within the peritoneal cavity. As the testicle descends through the inguinal canal and into the scrotum, it is accompanied by a saclike extension of peritoneum, otherwise known as the PV. After the testicle descends, the PV obliterates in the healthy infant and becomes a fibrous cord with no lumen. Thus, the scrotum should lose its connection with the abdomen. Without this connection, neither abdominal organs nor peritoneal fluid should make their way into the scrotum or inguinal canal. If the PV does not close, it is referred to as a patent processus vaginalis (PPV).

If the PPV is small in caliber and only large enough to allow fluid to pass, the condition is referred to as a communicating hydrocele. If the PPV is larger, allowing ovary, intestine, or other abdominal contents to protrude, the condition is referred to as a hernia. Multiple theories exist regarding the failure of PV closure. Smooth muscle has been identified in PPV tissue and not in normalperitoneum. The amount of smooth muscle present may correlate with the degree of patency. For example, higher amounts of smooth muscle have been found in hernia sacs than in the PPV of hydroceles. Investigation continues to determine the role of smooth muscle in the pathogenesis of this condition.

Frequency

United States

Incidence is 10-20 hernias per 1000 live births. While hernia location is more common on the right side, as many as 10% are bilateral.

Mortality/Morbidity

The greatest risk associated with a hernia is that the intestine becomes trapped inside the sac. This condition is referred to as incarceration. If left incarcerated, the bowel may become edematous. The increased pressure may impair venous drainage, leading to more edema, which may impair arterial inflow of the bowel and possibly the testis. When perfusion of the bowel is affected, a strangulated hernia exists. A strangulated hernia can lead to perforated bowel, peritonitis, sepsis, and death. As such, an incarcerated or strangulated hernia is a surgical emergency. If a strangulated bowel is reduced surgically at an early stage, viability may be preserved, and bowel resection may be avoided.

In females, the ovary or fallopian tube can enter hernia sacs and become incarcerated or strangulated. An incarcerated ovary is an urgent problem that may result in infarction of the ovary and pain; however, an incarcerated ovary does not carry the same risk of perforation and sepsis as seen with bowel perforation.

Sex

• Hernias are 6 times more common in boys than in girls.
• Bowel incarceration is more common in females than in males.
• In females an ovary or fallopian tube incarcerates more frequently than bowel. Therefore, overall incidence of bowel strangulation is lower in females than in males.

Age

Incidence of PPV decreases with age. In newborns, 80-94% have a PPV. Hernias are 20 times more common in infants weighing less than 1500 g than in the general population. As many as 30% of adults have a PPV at autopsy. Why all PPVs do not develop into a hernia or hydrocele is not understood.

CLINICAL

Section 3 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

History

A bulge in the groin or scrotal enlargement is the classic presentation of hernia or communicating hydrocele. Pain generally is not a prominent feature unless a hydrocele is infected or a hernia is strangulated. Frequently, parents report an intermittent bulge. The bulge may reduce at night while lying supine. A history of vomiting, colicky abdominal pain, or obstipation suggests bowel obstruction, which may occur with an incarcerated or strangulated hernia.

Physical

Examine the child in the supine and standing positions. If a bulge is apparent in the standing position, lay the child in the supine position. Resolution of the bulge in the supine position suggests a hernia or a hydrocele with a patent processus vaginalis (PPV).

• If the bulge is not readily apparent, perform a maneuver to increase intraabdominal pressure. For example, have children blow up balloons or press on their abdomens. Raising children's hands above their heads causes them to struggle and may reveal occult bulges that are not visible otherwise.
• Transillumination of the scrotum displays fluid in the TV, suggesting a hydrocele; however, this test is not completely reliable because the bowel also may appear to transilluminate.
• Bowel sounds in the scrotum are strongly suggestive of a hernia.
• A bulge below the inguinal ligament is suggestive of lymphadenopathy.
• Examiners may try to elicit the silk glove sign. Gently passing the fingers over the pubic tubercle may reveal a PPV. The thickened cord of a hernia or hydrocele sac within the spermatic cord provides the feel of 2 fingers of a silk glove rubbing together.
• Unless a PPV results in hernia or hydrocele, it often goes undetected upon physical examination.

Causes

Most hernias and hydroceles in children are due to idiopathic failure of the PV to close. Any condition that increases intraabdominal pressure can delay or inhibit this closure.

• The following is a list of conditions associated with hernia or hydrocele:
• • Cryptorchid testis
  • Hypospadias
  • Ambiguous genitalia
  • Epispadias and exstrophy of the bladder
  • Ventriculoperitoneal shunt
  • Liver disease with ascites
  • Abdominal wall defects
  • Continuous ambulatory peritoneal dialysis
  • Prematurity
  • Low birth weight
  • Family history
  • Hydrops
  • Meconium peritonitis
  • Chylous ascites
  • Cystic fibrosis
  • Connective tissue disease
  • Mucopolysaccharidosis
• Reactive hydroceles cause inflammation and fluid accumulation around the testicle and can develop for the following reasons:
• • Trauma
  • Torsion
  • Infection (eg, epididymoorchitis)
  • Abdominal or retroperitoneal operations that impair lymphatic drainage
• Hernia classification
• • Indirect hernias come through the internal ring and are caused by failure of the PV to obliterate. Indirect hernias compromise most inguinal hernias in children. The hernia may extend down the inguinal canal toward the labia or scrotum.
  • Complete inguinal hernias are indirect hernias that extend into the scrotum. The anatomic defect is similar to the defect of a communicating hydrocele, although the PPV is more widely patent in hernias.
  • Direct hernias protrude directly through the floor of the inguinal canal and are medial to the inferior epigastric vessels. In children, these hernias are rare and usually observed only after another inguinal surgery.
• Hydrocele classification
• • Communicating hydroceles involve a PPV that extends all the way into the scrotum. In this case, the PPV is continuous with the TV, which surrounds the testicle. The anatomic defect is identical to the defect with an indirect hernia. However, the communication is smaller so only fluid accumulates.
  • Noncommunicating hydroceles contain fluid confined to the scrotum within the TV. The PV is obliterated so the fluid does not communicate with the abdominal cavity. Such hydroceles are common in infants, and the hydrocele fluid is usually reabsorbed before the infant is aged 1 year.
  • Reactive hydroceles are noncommunicating hydroceles that develop from some inflammatory condition in the scrotum.
  • Hydrocele of the cord occurs when the PV obliterates above the testicle, but a small communication with the peritoneum persists. A saclike area within the inguinal canal fills with fluid. The fluid does not extend into the scrotum.
  • Hydrocele of the canal of Nuck occurs in girls when fluid accumulates within the PV in the inguinal canal.
  • Abdominoscrotal hydrocele occurs because of a miniscule opening in the PV. Fluid enters the hydrocele and becomes trapped. The hydrocele continues to enlarge and eventually extends upward into the abdomen.

DIFFERENTIALS

Section 4 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Other Problems to be Considered

Retractile testis
Epididymitis or orchitis
Scrotal trauma (eg, scrotal hematoma, hematocele, testicular rupture)
Inguinal lymphadenitis
Tumors of the testis (benign or malignant)
Tumors of the spermatic cord (eg, rhabdomyosarcoma)

WORKUP

Section 5 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Lab Studies

• Laboratory evaluation is generally not essential to the evaluation of hydroceles and hernias.
• Leukocytosis may be a sign of a strangulated hernia.
• Leukocytosis and a left shift suggest an infectious and/or inflammatory process (eg, epididymo-orchitis).

Imaging Studies

• Indications for scrotal or inguinal ultrasound
• • Suggestion of torsion (use duplex ultrasound to evaluate blood flow)
  • Suggestion of tumor of the spermatic cord
  • Suggestion of tumor of the testicle
  • Trauma and concern about testicular rupture
• Role of ultrasonography in the evaluation of asymptomatic patent processus vaginalis (PPV)
• • As noted above, PPV can be difficult to diagnose with physical examination.
  • When a unilateral inguinal hernia is discovered on physical examination, the chance of PPV on the contralateral side can be as high as 63% in children younger than 2 months. This prevalence decreases with age. However, up to 20% of patients develop an inguinal hernia on the contralateral side. This has led to interest in ultrasonography to help assess for contralateral PPV in the preoperative period.
  • Recent studies have shown a positive correlation with ultrasonography findings of PPV and intraoperative findings of PPV. The false-negative rate (ie, ultrasonography findings are normal, even when a proven PPV exists) is unknown. Further evaluation of this modality may reduce the need for exploration of the contralateral inguinal ring.
• Abdominal plane films rule out bowel obstruction from an incarcerated or strangulated hernia.

Procedures

• Manual reduction of incarcerated hernias: Necrotic bowel usually cannot be reduced, and an incarcerated hernia can progress to perforation in as few as 2 hours. For these 2 reasons, parents and primary care physicians are encouraged to reduce hernias. Surgical consultation is critical even if the hernia is reduced successfully. Manual reduction of incarcerated hernias incorporates the following procedure:
• • Administer sedation to the child.
  • Elevate the child's buttocks and apply a padded ice pack to the inguinal area to reduce swelling.
  • Slowly compress the hernia at its most distal aspect while holding 2 fingers of the opposite hand at the neck of the hernia. This technique prevents the hernia from being pushed alongside the inguinal canal.
  • Maintain pressure continuously. Ten or more minutes of slow continuous pressure often is required.
  • The hernia should slide slowly back into the abdomen.

TREATMENT

Section 6 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Medical Care

• No medical therapy is effective for a hernia or a communicating hydrocele. Aspiration and injection of sclerosing agents have been recommended for noncommunicating hydroceles in adults, but this therapy is relatively contraindicated in children. Because most hernias and hydroceles in children are associated with a patent processus vaginalis (PPV), sclerosing agents may damage intraabdominal contents and are not likely to correct the underlying pathology. Anti-inflammatory agents may be used in the setting of a reactive hydrocele.
• Hydroceles following varicocelectomy: A recent study found that hydroceles can develop in 12% of children undergoing surgery for varicoceles. Conservative management (observation or aspiration) results in resolution of 80% of these hydroceles. Surgical correction was successful in only one third of these patients following varicocelectomy.

Surgical Care

Hernias and hydroceles are similar, but their natural histories differ. Spontaneous closure does not occur in frank hernias, and the risk of incarceration is significant. In particular, a great risk of incarceration exists in premature children. As many as 60% of hernias in premature infants incarcerate within the first 6 months after birth. For these reasons, surgical repair is generally accepted as the appropriate treatment for an inguinal hernia in children and adults.

Unlike hernias in infants, many newborn hydroceles resolve because of spontaneous closure of the PPV early after birth. The residual noncommunicating hydrocele does not wax and wane in volume, and no silk glove sign is present. The fluid in the hydrocele usually is reabsorbed into the body before the infant is aged 1 year. Because of these facts, observation is often appropriate for hydroceles in infants.

• Hydroceles should be repaired if they do the following:
• • Fail to resolve before the individual is aged 2 years
  • Cause discomfort
  • Enlarge or are clearly waxing and waning in volume
  • Are unsightly
  • Become infected (very rare)
• A hernia or hydrocele may protrude intermittently. Not infrequently, a bulge in the child's groin is noted by the parents or a primary care physician. Often, this bulge cannot be reproduced during a consultation, but thickening of the cord structures ipsilateral to the side with a history of a bulge (silk glove sign) is suggestive of a PPV. Such a situation is sufficient indication for inguinal exploration. A photograph of the area when the bulge is present may help clarify the diagnosis.
• Specific conditions or demographics and timing of surgery
• • If an incarcerated hernia cannot be reduced or signs suggest that the hernia is strangulated, schedule surgery emergently.
  • In full-term infants with no history of incarceration, schedule surgery as soon as possible on an outpatient basis.
  • For preterm neonatal intensive care unit (NICU) infants weighing 1800-2000 g, schedule surgery before hospital discharge.
  • For formerly premature infants younger than 60 weeks postconceptual age, schedule surgery as soon as possible with 24-hour postoperative monitoring for apnea and other anesthesia-related complications.
• Intraoperative details
• • Examine the child to confirm presence of testis.
  • Make a small inguinal incision.
  • Enter the inguinal canal and dissect the PV, which is the hernia sac or hydrocele sac, free of the vas deferens and vessels. Optical magnification is beneficial especially in premature infants and small children.
  • Reduce the sac contents (ie, abdominal organs, fluid) into the abdomen if the sac contents appear healthy.
  • If the contents of the sac appear compromised or cannot be reduced, open the sac and enlarge the inguinal ring. Ischemic bowel may show improvement in vascularity. Necrotic contents should be resected.
  • Ligate the sac at or above the internal ring.
  • The testicle sometimes is delivered into the incision, and the distal end of the sac is excised or everted around the testes (Bottle operation). These procedures are advised to avoid the later development of a postoperative noncommunicating hydrocele.
  • Reposition the testis in the scrotum. If the testis does not remain in the bottom of the scrotum, cryptorchidism may be present and orchiopexy should be performed at that time.
  • Inspect the internal ring to ensure that any abdominal contents are reduced completely.
  • Reinforce the internal ring if it was opened or if it appears larger than normal caliber.
  • Local anesthesia may be injected subcutaneously, or an inguinal nerve block may be performed.
  • Sew the fascial layers and skin closed.
• Contralateral exploration with inguinal hernias is performed as indicated.
  • When an inguinal hernia is present, some urologists and surgeons perform a contralateral groin exploration. This is intended to detect an occult PPV that may lead to a hernia on the opposite side (metachronous contralateral hernia.)
  • The Goldstein test can determine when to perform a contralateral exploration. In this test, the abdomen is insufflated with air through the hernia sac, which is opened during surgery. Crepitus in the opposite groin is a positive test result, suggesting a contralateral PPV and warranting a contralateral exploration. Alternatively, a laparoscope can be used to detect an occult contralateral PPV.
• Laparoscopy has an evolving role in hydrocele and hernia surgery.
  • As mentioned above, exploratory laparoscopy may be carried out through a separate incision at the umbilicus or through the hernia sac, once it has been opened. This allows inspection of the contralateral inguinal ring and assessment of patency. Additional procedures may then be performed as needed.
  • Laparoscopic hernia repair in children is not performed as commonly as in adults. Several European centers have used a technique in which the hernia sac is not excised but simply closed at the neck with suture. Mesh is not commonly used in children as it is with adults. Results to date are favorable, although recurrence rates are higher than with open repair.
  • A recent series by Kaya et al from Germany (2006) reported favorable results with the laparoscopic approach compared with reduction and repair of incarcerated inguinal hernias in children. They reported no complications and no recurrences. However, the details and length of follow-up were not clearly defined.

Activity

Convalescence following hernia or hydrocele surgery is usually straightforward.

• Pain control
  • Infants - Ibuprofen 10 mg/kg every 6 hours; acetaminophen 15 mg/kg every 6 hours; avoid narcotics because of the risk of apnea
  • Older children - Acetaminophen with codeine (1 mg/kg codeine) every 4-6 hours
• For 2 weeks after surgery, straddle positions (eg, bike, big wheel) should be avoided to prevent displacement of the mobile testes out of the scrotum, which causes secondary cryptorchidism.
• In children of ambulatory age, activities should be limited as much as possible for 1 month.
• In children of school age, strenuous activities and active sports should be limited for 4-6 weeks.
• Because most hernia and hydrocele surgery is performed on an outpatient basis, the patient may return to school as soon as comfort level allows (usually 1-3 d postoperation).

FOLLOW-UP

Section 7 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Further Inpatient Care

• Postoperative details
  • Formerly premature infants younger than 60 weeks postconceptual age should be admitted for 24 hours to monitor for apnea and other anesthesia-related complications.

Complications

• Overall operative complication rate is 1.7-8%.
• • Infertility may occur upon bilateral injury to the vas deferens or upon injury to the vas of a solitary testis. Presence of a vas-like structure in the pathology specimen does not necessarily indicate injury to the vas because up to 6% of specimens contain mullerian ductal remnants with a histologic appearance very similar to the vas.
  • Testicular atrophy may occur because of intraoperative injury to the testicular blood supply. Incarcerated hernias may compromise blood flow to the testicle; the rate of testicular atrophy after repair of an incarcerated hernia can be as high as 19%.
  • As with any surgery, hematomas may occur. A hematoma usually does not need to be explored unless the hematoma continues to enlarge. Scrotal elevation is encouraged, and analgesics are administered.
  • As in any surgery, wound infections can occur.
  • Hypesthesia and neuropathic pain can result from nerve entrapment or injury.
  • Secondary cryptorchidism may occur because of excessive scar formation and ascent of the testicle with growth.

Prognosis

• With open surgery, ipsilateral recurrence rates are less than 1%. The ipsilateral recurrence rate following laparoscopic inguinal hernia repair is 3.4%.
• Recurrences are usually associated with comorbid conditions. The occurrence of a metachronous contralateral hernia is inversely related to age and can be as high as 12%.

MISCELLANEOUS

Section 8 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Special Concerns

• Hernias can be found in children with genital ambiguity and disorders of sexual differentiation. Although rare, these conditions deserve special consideration.
• In phenotypic males with müllerian-inhibiting substance (MIS) deficiency, persistent müllerian structures (eg, fallopian tube, uterus) may herniate through a patent processus vaginalis. In fact, the initial finding may be a hernia in many of these patients.
• In phenotypic females with a 46 XY genotype and androgen insensitivity, bilateral inguinal hernias may be found to contain the testes. In these instances, a biopsy of the gonad is recommended to establish the genotypic sex and aid in further management. Immediate versus delayed orchiectomy must then be considered.
• Fortunately, these circumstances represent the minority of children with inguinal hernias.

REFERENCES

Section 9 of 9

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

• Boocock GR, Todd PJ. Inguinal hernias are common in preterm infants. Arch Dis Child. Jul 1985;60(7):669-70. [Medline].
• Esposito C, Valla JS, Najmaldin A, et al. Incidence and management of hydrocele following varicocele surgery in children. J Urol. Mar 2004;171(3):1271-3. [Medline].
• Hata S, Takahashi Y, Nakamura T, et al. Preoperative sonographic evaluation is a useful method of detecting contralateral patent processus vaginalis in pediatric patients with unilateral inguinal hernia. J Pediatr Surg. Sep 2004;39(9):1396-9. [Medline].
• Hosgor M, Karaca I, Ozer E, et al. The role of smooth muscle cell differentiation in the mechanism of obliteration of processus vaginalis. J Pediatr Surg. Jul 2004;39(7):1018-23. [Medline].
• Kapur P, Caty MG, Glick PL. Pediatric hernias and hydroceles. Pediatr Clin North Am. Aug 1998;45(4):773-89. [Medline].
• Kaya M, Huckstedt T, Schier F. Laparoscopic approach to incarcerated inguinal hernia in children. J Pediatr Surg. Mar 2006;41(3):567-9. [Medline].
• Schier F, Montupet P, Esposito C. Laparoscopic inguinal herniorrhaphy in children: a three-center experience with 933 repairs. J Pediatr Surg. Mar 2002;37(3):395-7. [Medline].
• Shirvani AR, Ortenberg J. Communicating hematocele in children following splenic rupture: diagnosis and management. Urology. Apr 2000;55(4):590. [Medline].
• Skoog SJ, Conlin MJ. Pediatric hernias and hydroceles. The urologist''s perspective. Urol Clin North Am. Feb 1995;22(1):119-30. [Medline].
• Weber T, Tracy T. Groin hernias and hydroceles. In: Pediatric Surgery. 2nd ed. WB Saunders Co;1993:562.
• Wiener ES, Touloukian RJ, Rodgers BM, et al. Hernia survey of the Section on Surgery of the American Academy of Pediatrics. J Pediatr Surg. Aug 1996;31(8):1166-9. [Medline].
• Yerkes EB, Brock JW, Holcomb GW, Morgan WM 3rd. Laparoscopic evaluation for a contralateral patent processus vaginalis: part III. Urology. Mar 1998;51(3):480-3. [Medline].

Article Last Updated: Jun 16, 2006