Urethral meatal stenosis is a narrowing (stenosis) of the opening of the urethra at the external urinary meatus , thus constricting the opening through which urine leaves the body from the urinary bladder.
Symptoms and signs
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Visible narrow opening at the meatus in boys
-
Irritation, scarring or swelling of the meatus in boys
-
Abnormal strength and direction of urinary stream
-
Discomfort with urination (dysuria and frequency)
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Incontinence (day or night)
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Bleeding (hematuria) at end of urination
-
Urinary tract infections - increased susceptibility due to stricture
Causes
The protection provided by the
foreskin for the
glans penis and
urinary meatus has been recognized since 1915. In the absence of the foreskin the meatus is exposed to mechanical and chemical irritation from ammoniacal diaper (nappy) that produces blister formation and ulceration of the urethral opening, which eventually gives rise to meatal stenosis (a narrowing of the opening).
[ Published online ahead of print on 22 December 2016.] Meatal stenosis may also be caused by
ischemia resulting from damage to the
Penile frenulum artery during circumcision.
Risk factors
Frisch & Simonsen (2016) carried out a very large-scale study in Denmark, which compared the incidence of meatal stenosis in Muslim males (mostly
Circumcision) with the incidence of meatal stenosis in ethnic Danish males (mostly non-circumcised). The risk of meatal stenosis in circumcised males was found to be as much 3.7 times higher than in the non-circumcised males.
Diagnosis
In males, history and
physical exam is adequate to make the diagnosis. In females, VCUG (voiding cystourethrogram) is usually diagnostic. Other tests may include:
Prevention
In the newborn
According to Frisch & Simonsen (2016), "the foreskin is protective against urinary stricture disease" (meatal stenosis).
Frisch & Simonsen (2016) call for a "thorough reassessment of the burden of urethral troubles and other adverse outcomes after non-therapeutic circumcision of boys."
After hypospadias repair
Meir & Livne (2004) suggest that use of a broad spectrum antibiotic after
hypospadias repair will "probably reduce meatal stenosis rates",
while Jayanthi (2003) recommends the use of a modified Snodgrass hypospadias repair.
Treatment
In females, meatal stenosis can usually be treated in the physician's office using
local anesthesia to numb the area and dilating (widening) the urethral opening with special instruments.
In males, it is treated by a second surgical procedure called meatotomy in which the Urinary meatus is crushed with a straight mosquito hemostat and then divided with fine-tipped scissors.
Prognosis
Most people can expect normal urination after treatment.
Incidence
Numerous studies over a long period of time clearly indicate that male
circumcision contributes to the development of urethral stricture. Among circumcised males, reported incidence of meatal stricture varies. Griffiths
et al. (1985) reported an incidence of 2.8 percent.
Sörensen & Sörensen (1988) reported 0 percent.
Cathcart
et al. (2006) reported an incidence of 0.55 percent.
Yegane
et al. (2006) reported an incidence of 0.9 percent.
Van Howe (2006) reported an incidence of 7.29 percent.
In Van Howe's study, all cases of meatal stenosis were among circumcised boys. Simforoosh
et al. (2010) reported an incidence of 0.55 percent.
According to Emedicine (2016), the incidence of meatal stenosis runs from 9 to 20 percent.
Frisch & Simonsen (2016) placed the incidence at 5 to 20 percent of circumcised boys.
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