• Clinical science

Disorders of sex development

Summary

Disorders of sex development are a group of congenital conditions that affect the development of the chromosomal, gonadal, or phenotypic sex. The underlying genetic mutations affect the number and function of sex chromosomes (e.g., in Turner syndrome), lead to structural changes with altered sensitivity of hormone receptors (e.g., androgen insensitivity syndrome), or alter the function of enzymes responsible for sex hormone synthesis (e.g., congenital adrenal hyperplasia). The most characteristic clinical feature is the development of a sexual phenotype which does not correspond to the sexual genotype. Other common features include reduced fertility or infertility and concomitant organ malformations (e.g., cardiac abnormalities). Disorders of sex development can also present with difficulties in gender identification and cause considerable psychological distress. The diagnosis of these conditions is based on characteristic clinical features, evaluation of hormone levels, and genetic testing. Management includes hormone substitution, possibly sex reassignment surgery, and psychological counseling.

Congenital adrenal hyperplasia

Androgen insensitivity syndrome

References:[1]

Aromatase deficiency

References:[2][3]

5-alpha-reductase deficiency

  • Synonym: pseudovaginal perineoscrotal hypospadias (PPSH)
  • Etiology: rare autosomal recessive loss-of-function mutation of chromosome 2
  • Karyotype: 46,XY
  • Pathophysiology
  • Clinical features
    • Female external genitalia at birth, sometimes with pseudovaginal perineoscrotal hypospadias
    • Internal urogenital organs are male
    • In puberty, increasing synthesis of testosterone leads to virilization (phallic growth, testicular descent, development of male gender identity).
  • Diagnostics
  • Therapy

References:[4][5]

Klinefelter syndrome

References:[6][7][8]

Ovotesticular disorder of sex development

Turner syndrome

References:[6][9][10][11][12][13][14]

Pure gonadal dysgenesis

References:[15]

Swyer syndrome

References:[16][17][18]