With thanks to Dr Nikolina Kyprianou for this article and to Mr Devesh Misra, consultant paediatric urologist at the Royal London Hospital, for checking it.
Hypospadias is a congenital abnormality where the male urethral opening is displaced ventrally. It may be displaced anywhere within the glans, the shaft of the penis, the scrotum, or the perineum. It results from failure of the urethral folds to close during fetal development and it is often associated with abnormal penile curvature (chordee) due to disrupted development of the penile shaft. Males with severe uncorrected forms of hypospadias may have difficulties in controlling their urinary stream which may require urination in a sitting position. They can also have erectile dysfunction and infertility (due to impaired semen delivery).
The location of the urethral meatus classifies the hypospadias and its severity.
3 classes of severity:
- 1st degree: urethral opening within the glans/subcoronal (50% of cases)
- 2nd degree: urethral opening on the penile shaft (20% of cases)
- 3rd degree: urethral opening within the scrotum or perineum (30% of cases)
Hypospadias results due to disruption of the androgenic stimulation that is required for the normal male external genitalia to develop. Environmental factors have been found to be associated with hypospadias suggesting a multifactorial aetiology. These include:
- Advanced maternal age
- Pre-existing maternal diabetes mellitus
- Gestational age before 37 weeks
- History of paternal hypospadias
- Exposure to smoking and pesticides
Hypospadias is one of the most common congenital abnormalities with an incidence from 0.3 to 0.7% in live male births. It is more common in the Caucasian population and in those of Jewish and Italian descent.
The diagnosis is usually made during the newborn examination. Physical findings include:
- The appearance of two urethral openings: the first one will be in the normal position at the end of the glans, which will be a blind ending urethral pit. The second is the abnormally located true urethral meatus.
- Abnormal foreskin due to its incomplete closure around the glans leading to the appearance of a dorsal hooded prepuce.
- Abnormal penile curvature (chordee).
In 6% of cases the foreskin is normal and the urethral abnormality only becomes evident during/after circumcision when the glans of the penis is visualised.
Isolated hypospadias: this is only rarely associated with upper genitourinary tract abnormalities and therefore there is no need to
routinely perform imaging studies of the tract.
Cryptorchidism and hypospadias: these patients have an increased risk of disorders of sex development. Cryptorchidism is present in 10% of
patients with hypospadias and is higher in patients with proximal hypospadias (eg. scrotal or perineal urethral meatus). Proximal hypospadias on its own is also associated with disorders of sex development. These patients should be referred to a specialist so that they can have the following investigations:
- Pelvic USS to evaluate internal genitalia.
- Karyotype analysis.
- Serum electrolytes as a screen for salt-wasting forms of congenital adrenal hyperplasia.
Hypospadias with other organ system anomalies eg. Congenital cardiac disease, imperforate anus, limb malformations, or cleft lip. These patients require renal and bladder USS because they are at risk of upper tract abnormalities. They should be referred to a specialist who will also perform genetic testing.
Parents should be advised not to circumcise their baby in order to preserve the foreskin and optimise later surgical choices. These patients need to be referred to the local paediatric urologist who will determine the severity of the hypospadias and the need and timing for surgical correction.
The goal of surgery is to create a straight penis by repairing any curvature (orthoplasty), to create a urethra with its meatus at the tip of the penis (urethroplasty), to reform the glans into a more natural conical configuration (glansplasty), to achieve cosmetically acceptable penile skin coverage, and to create a normal-appearing scrotum. Surgery is usually performed within the first year of life because early correction is associated with improved wound
healing, reduced rate of complications and improved emotional and psychological result. The repair is usually planned as a single-stage procedure, but in infants with severe hypospadias a two-stage repair may be necessary.
With the use of modern instruments, sutures and antibiotics and by performing the procedure at a younger age, the repair of hypospadias has been successful.
For a useful leaflet for parents please follow link and download the PDF document: http://www.patient.co.uk/health/Hypospadias.htm
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