Meatal stenosis

Meatal stenosis is a narrowing of the meatus (the opening of the urethra). Meatal stenosis is extremely rare in intact boys with a protective foreskin. About twenty percent of circumcised boys develop meatal stenosis. Meatal stenosis may be prevented by avoiding child circumcision, which is a medically-unnecessary, non-therapeutic surgical amputation procedure.

Background

Genital disorders are commonly encountered in the office of the primary care physician. Meatal stenosis is a relatively common acquired condition occurring in 10%-20% of males who are circumcised. This disorder is characterized by an upward deflected, difficult-to-aim urinary stream and, occasionally, dysuria and urgent, frequent, and prolonged urination. Surgical meatotomy is curative.

Pathophysiology

After circumcision and the loss of foreskin protection, a child who is not toilet-trained persistently exposes the meatus to urine, resulting in inflammation (ammoniacal dermatitis) and mechanical trauma as the meatus rubs against a wet diaper (nappie). This causes the loss of the delicate epithelial lining of the distal urethra. This loss may result in adherence of the epithelial lining at the ventral side, leaving a pinpoint orifice at the tip of the glans. Because this condition is exceedingly rare in intact children, circumcision is believed to be the most important causative factor of meatal stenosis.

Another hypothetical cause of this condition is ischemia due to damage to the frenular artery during circumcision, resulting in poor blood supply to the meatus and subsequent stenosis. In a prospective study of circumcised boys, Van Howe (2006) found meatal stenosis in 24 of 239 (7.29%) children older than 3 years, making meatal stenosis the most common complication of circumcision.

Epidemiology

Frequency

International

Meatal stenosis affects 10%-20% of males who are circumcised in infancy.

Mortality/Morbidity

Meatal stenosis carries no risk of mortality.

Morbidity is limited to the clinical symptoms and complications of surgical repair, including bleeding, infection, and recurrence.

Race

Meatal stenosis has no racial predilection. The condition can occur in circumcised males independent of ethnicity.

Gender

Meatal stenosis occurs only in males.

Age

Children who are not toilet-trained are more prone to develop meatal stenosis after circumcision because of exposure of the meatus to ammonia from the urine in diapers. Most children who are toilet-trained can verbalize their difficulties during micturition to their caregivers.

Clinical presentation

History

Patient history may include the following:

• Difficult-to-aim (upward deflected), high-velocity (long distance) stream of urine
• Pain upon initiation of micturition
• Need to stand back from toilet or sit during urination
• Burning at meatus
  • Blood spots in underwear
  • Urgent, frequent, and prolonged emptying of the bladder

Physical

Meatal stenosis can be suspected based on the presence of a small meatus during examination, particularly if, with lateral traction, the ventral edges of the meatus appear fused.

Observation of the child while voiding helps immensely in confirming the diagnosis of the disorder.

If the physician desires to calibrate the meatus, Litvak et al. report that the meatus in children younger than 1 year will accept a lubricated 5F feeding tube. They also report that, in children aged 1-6 years, an 8F feeding tube should pass without difficulty.

Causes

In a child who is circumcised, persistent exposure of the meatus to urine and mechanical trauma from rubbing against a wet diaper results in ammoniacal dermatitis, loss of meatal epithelium, and fusion of its ventral edges. This results in a pinpoint orifice at the tip of the glans.

Other causes of meatal stenosis include the following:

• Unsuccessful hypospadias repair
• Trauma
• Prolonged catheterization
• Balanitis xerotica obliterans
  • Balanitis xerotica obliterans (BXO), which is an unusual condition that causes a whitish discoloration and dry appearance of the glans, can also cause meatal stenosis.
  • A 10-year retrospective series at Boston Children's Hospital included 41 patients with a median age of 10.6 years. Eighty-five percent of the patients were aged 8-13 years. The disease process was found to involve the prepuce, the glans, and, sometimes, the urethra. The most common referral diagnoses included phimosis (52%), balanitis (13%), and buried penis (10%). In 46% of the patients, circumcision was curative. Twenty-seven percent (11 patients) had meatal involvement that was treated by meatotomy and meatoplasty, and 22% required extensive plastic procedures of the penis, including buccal mucosal grafts.
  • In children with BXO, meatal stenosis seems to be quite common.
  • Although BXO is difficult to treat, meatotomy yields good results in patients with BXO.

Differential diagnoses

Circumcision

Workup

Laboratory studies

Meatal stenosis does not cause urinary tract infections, hydronephrosis, or any form of obstruction of the lower urinary tract. For this reason, no further urological investigation is warranted. If the diagnosis is in question, observing the child void, with particular attention to the force of the stream (increased), caliber of the stream (decreased), and duration of the voiding episode (usually prolonged), is helpful. If an elimination disorder is suspected, noninvasive urodynamics such as uroflow with electromyography (pad electrodes) and measurement of bladder capacity and postvoid residuals could be indicated. If associated infection is a possibility, urinalysis with culture should be obtained.

Treatment and management

Surgical care

Serial dilatation results in small tears of the meatus, which are followed by secondary healing. In the long term, this creates a tighter stricture at the tip of the penis; therefore, this procedure is discouraged.

Meatotomy is the definitive treatment for meatal stenosis. Meatotomy is a simple procedure in which the ventrum of the meatus is crushed (for hemostasis) for 60 seconds with a straight mosquito hemostat and then divided with fine-tipped scissors.

Brown et al. (1997) reported excellent results following 130 office meatotomies with only 2 recurrences of meatal stenosis and 1 patient with bleeding requiring stitches. They also cited the cost-effectiveness of this treatment and noted good patient tolerance when a caring approach is used to reassure the child before and during the procedure. In this series, parents were encouraged to remain with the children during the operation, as their presence seemed to have a calming effect.

• If the caregivers and the patient are cooperative, this procedure can be performed in the office of the physician using a topical eutectic mixture of local anesthetics (EMLA cream) applied liberally over the entire glans and secured in place for at least one hour with an occlusive dressing.
• After being in place for one hour, the dressing is removed and the penis is prepared and draped into a sterile field.
• Throughout this procedure, reassure the child and tell him what is being done.
• Introduce one blade of a straight mosquito hemostat into the meatus and crush the ventrum of the meatus (approximately 3 mm) by closing the hemostat. This provides adequate hemostasis in most cases.
• Divide the crushed area with a straight fine-tipped scissor and apply an antibiotic ointment.
• After the operation, it is critical that the caregivers separate the edges of the meatus and apply antibiotic ointment or petroleum jelly twice a day for 2 weeks and then once a day for another 2 weeks to prevent one side of the meatotomy from adhering to the other side. Some medical professionals recommend dilation with a lubricated feeding tube or the tip of an ophthalmic ointment tube for a period of 4-8 weeks.
• In a survey of office pediatric urologic procedures, which included meatotomy, lysis of labial adhesions, and newborn circumcision, Smith & Smith (2000) found that 95 of 99 parents stated that they were satisfied with their decision to have these procedures performed in the office, and 95% reported good outcomes (only 1 patient had recurrent meatal stenosis).
• Mild dysuria may be present for 1-2 days after meatotomy. If dysuria results in urinary retention, placing the child in a tub of warm water may stimulate micturition.

Consultations

If the primary care physician is unwilling to perform a meatotomy, encourage consultation with a pediatric urologist.

Activity

After meatotomy, instruct caregivers to dress the child in loose underwear for 24 hours.

Restrict activities, such as contact sports, bicycle rides, and playground activities, for 3-4 days.

Follow-up

Further outpatient care

Following meatotomy, caregivers should separate the edges of the meatus and apply antibiotic ointment or petroleum jelly twice a day for 2 weeks and then once a day for 2 more weeks.

Complications

Complications include bleeding during or after meatotomy, infection, and recurrence. All of these complications are quite rare and respond readily to appropriate management.

Mild dysuria may persist for 1-2 days. Placing the child in a tub of warm water may provide relief.

Prognosis

Prognosis is excellent. Meatotomy cures the symptoms of most patients.

File:Kid Friendly Approach to Meatal Stenosis.pdf