Hypospadias

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Original Author(s): Dr David Thompson, Dr Alex Cho (paediatric surgeon) and Adam Bonfield
Last updated: 3rd January 2019
Revisions: 11

Original Author(s): Dr David Thompson, Dr Alex Cho (paediatric surgeon) and Adam Bonfield
Last updated: 3rd January 2019
Revisions: 11

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Hypospadias is a congenital defect causing the urethral meatus to be located at an abnormal site, usually on the under side of the penis rather than at the tip.

Epidemiology

Incidence of hypospadias is around 1 in 300 male births. Incidence is thought to be increasing.

Pathophysiology

Hypospadias occurs due to arrest of penile development, leading to hypoplasia of the ventral tissue of the penis.

Clinical Features

Largely a diagnosis made from examination, parents may present describing abnormal urinary flow, i.e. not from the tip of the penis, or abnormal penile curvature during erections.

There are 3 key features of hypospadias, although not all 3 are required for the condition:

1) Ventral opening of the urethral meatus

2) Ventral curvature of the penis or “Chordee

3) Dorsal hooded foreskin

Classification

This is largely related to the site of the urethral meatus. It can be described as: Glandular, coronal, shaft (distal, mid, proximal), scrotal, perineal (figure 1).

Figure 1: Hypospadias classification

Differential Diagnosis

It is important to eliminate underlying disorder of sex development (DSD) if associated with unilateral or bilateral undescended testis. Congenital Adrenal Hyperplasia is a diagnosis that must not be missed and should be considered in females with ambiguous genitalia. If not detected early this can lead to a salt wasting crisis due to cortisol and aldosterone deficiency with androgen excess.

Investigations

If not concerned about DSD, no other investigation is routinely required.

If there are concerns about DSD, investigations that may be considered are:

  • Detailed history and examination
  • Karyotype
  • Pelvic ultrasound scan
  • Urea and Electrolytes
  • Endocrine hormones: Testosterone, 17 alpha-hyroxyprogesterone, LH, FSH, ACTH, renin, aldosterone

Management

Management involves intervention for both cosmetic and functional indications. Correction of the 3 features of the hypospadias can be undertaken through a multitude of surgical techniques, but procedures vary depending on individual presentation, surgical and parental preference (and patient if old enough).

Urethroplasty is the mainstay of treatment. This can either be performed as a single stage or a 2-stage repair, using a graft. This is preferentially a preputial graft harvested from the foreskin hence the need to advise against circumcision (see note below).

Aims of urethroplasty:

  • Bringing the meatus to the glans of the penis
  • The chordee is corrected to straighten the penis
  • The dorsal foreskin is managed with either circumcision or reconstruction, depending on anatomy, parental and surgical preference.

NOTE – It is important to highlight to family’s that circumcision should not be performed until after discussion about reconstruction with a specialist has occurred, as the foreskin can form a vital part reconstruction.

Complications

Short term complications

Following surgery these patients will tend to have a penile dressing as well as a urethral catheter, to protect the surgical reconstruction. This urethral catheter may block, requiring further management such as flushing. The urethral catheter may also become displaced or kinked and therefore there should be careful inspection if not draining.

The urethral catheter may also cause pain and bladder spasms. Urine must be freely draining before assigning symptoms to bladder spasms which can otherwise be treated with anticholinergics such as oxybutynin.

Other short-term complications include bleeding and infection.  It is important to liaise with the surgical team in order to confirm the anatomy and nature of the reconstruction underneath as this will alter how one manages the presenting complication.

Longer term complications

Long term issues include urethral fistula which occurs in around 5-10% for a distal repair and rises to 30% for proximal repair. There is also risks of meatal or urethral stenosis which may require further intervention.  These longer term complications may occur many years after the original repair and these patients may need to be re-referred if no longer under routine follow-up.

References

[1] Thomas, D.F., Duffy, P.G. and Rickwood, A.M. eds., 2008. Essentials of paediatric urology (pp. 73-91). London: Informa Healthcare.
[2] Puri, P. and Höllwarth, M.E. eds., 2009. Pediatric surgery: diagnosis and management. Springer Science & Business Media.
[3] Godbole, P.P., Gearhart, J.P. and Wilcox, D.T. eds., 2008. Clinical problems in pediatric urology. John Wiley & Sons.

 

First author: Dr David Thompson

Senior review: Mr Alex Cho