Paediatrics: Management of sex development disorders

2021-03-02 12:00 AM

Most infants presenting with a disorder of sexual differentiation will pre-sent with ambiguous genitalia at birth.

Disorder of sexual differentiation

Investigations

Laboratory

  • Genetic sex determination: FISH for Y and X chromosomes; karyotype(takes 3–5 days).
  • Serum electrolytes.
  • Blood sugar (hypoglycaemia).
  • Adrenal androgens: plasma testosterone; 17-OH progesterone; urine steroid profile; LH and FSH.
  • Molecular genetic studies; blood (DNA).

If a male/mosaic karyotype is confirmed, further investigations are directed at establishing whether testicular tissue is capable of producing androgens:

  • hCG stimulation test;
  • testosterone: DHT ratio;
  • androgen receptor binding studies;
  • genital skin biopsy (fibroblast).

Imaging studies

  • US scan pelvis: anatomy of urogenital sinus/vagina/uterus.
  • US scan abdomen: renal anomalies.
  • Urogenital sonogram.
  • MRI.

Internal examination

  • Examination under anaesthesia (+/– cystography).
  • Laparoscopy.
  • Gonadal biopsy.

Management

This is professionally challenging and requires a multidisciplinary team including the following:

  • Paediatric endocrinologist.
  • Neonatologist.
  • Paediatric urologist.
  • Gynaecologist.
  • Geneticist.
  • Radiologist.
  • Psychologist.

Clinical biochemistry

Most infants presenting with a disorder of sexual differentiation will pre-sent with ambiguous genitalia at birth.

  • Parents and their relatives will be anxious to know the sex of their newborn baby.
  • Decisions about an infant’s sex (sex assignment) must be delayed until the multidisciplinary team has carried out a thorough assessment.
  • Birth registration must be delayed until this has been completed and an agreement on sex assignment has been made with the parents.