Undescended/ maldescended testes

• Undescended – not in scrotum by age of 3 months
  • 5% per cent of boys have a UDT at birth
  • 1–2% at three months
  • 1% at one year
  • hence, it is uncommon for testes to descend after three months
  • May have undeveloped scrotum
  • second most common paediatric surgical condition after inguinal hernias
• Ectopic testes
  • deviated from normal path of descent from abdomen – > inguinal canal – > scrotum. 
  • May be found in another region
• Ascending testes
  • Initially descended but then moved higher over time
  • Usually abnormal persisting fibrotic remnant of processus vaginalis
  • Regular re-examination recommended for boys even if previously in the scrotum
• Impalpable testes
  • 30% are inguinal, 20% intra-abdominal, 10% ectopic, 40% may have testicular regression
  • Useful size comparision approximates glans penis
• Retractile testis
  • Can be brought into the scrotum but retracts back – normal variant due to cremaster muscle

Classification

• Classify the testis as normal, high scrotal, supra-scrotal or impalpable 
• Ectopic testes can be in the perineum, femoral region, pre-penile region and even the opposite hemiscrotum

Risk factors 

• maternal smoking
• family history
• low birth weight
• prematurity

No need for USS prior to referral

Treatment

• Refer at 3-6 months for unilateral UDT, orchidopexy between 6-12 months to protect fertility potential and decrease the risk of malignant changes
• If high at the neck of the scrotum – yearly review – risk of ascending
• Bilateral or any other genital abnormality hypospadias or bifid scrotum 🡪
  • warrant investigation for a disorder of sexual differentiation such as
    • congenital adrenal hyperplasia ( can have lethal salt-wasting consequences)
• Will have examination under anaesthesia and diagnostic laparoscopy

Prognosis

• infertility, subfertility : UDT will have reduced germ cells,If not fixed by 15 months likely to have nil
• Bilateral fixed with orchidopexy – fertility rate 50%
• Little evidence that orchidopexy improves fertility
• Risk of testicular cancer at 2% (5 x higher than population). Detection easier if had orchidopexy