DSD (Disorders of Sexual Development) is a social emergency at birth. For every thousand live births,1-2 individuals will be affected by ambiguous genitalia.
DSDs can present at different age groups to different health professionals but pediatric and adult endocrinologists play a central role in diagnosis, support and management.
DSDs represent a broad range of conditions with many causes like congenital adrenal hyperplasia, testicular feminsing syndrome (androgen insensitivity syndrome), 5 alpha reductase deficiency etc. Our pediatric endocrinologist understands the the basic biology of sex development and steroid synthesis and can help in elucidating the causes of these disorders.
Gender identity or the psychological sex refers to the inner sense of one’s maleness or femaleness and is determined by the sex of rearing or gender role. Sexual Identity or the organic sex refer to the biologic sexual differentiation and is determined by chromosomes, gonads, internal genitalia, external genitalia and hormones.
When there is discordance between any two of the organic sex criteria, it is called intersex or DSD. When there is a discordance between organic and psychological sex components, it is called transsexuality.
During early embryogenesis, the gonads and internal structures of male and female fetuses are phenotypically identical and bipotential. The bipotential gonad differentiates into either an ovary or a testis, depending on specific gene expression. The first step in male sex development is expression of the sex-determining region on the Y chromo- some (SRY), which occurs around the sixth week of gestation. SRY triggers further sex-determining genes and transcription factors that are necessary for maturation and differentiation of cell types in the testis, including Sertoli and Leydig cells. In the absence of SRY, the gonadal cells in the XX embryo develop into ovarian granulosa and theca cells. The absence of AMH allows the müllerian ducts to develop into the internal female genitalia (uterus, fallopian tubes, and upper one-third of the vagina), and the wolffian ducts regress. Without testosterone and DHT, the genital tubercle will form the clitoris, the urethral folds become the labia minora, and the labioscrotal swellings become the labia majora, leading to a female external phenotype.
Pediatric endocrinologist will first achieve a correct diagnosis and then help in monitoring hormones, tumor risk, fertility potential, and counselling families. In some situations, a diagnosis might influence sex designation.
Some DSDs present in teenage years or even in adulthood. Adult endocrinologist have a crucial role in managing young people who present in adulthood as well as long term follow up of individuals diagnosed in children. Our pediatric and adult endocrinologist with training in both pediatric and adult endocrinology is unique in taking care of all these difficult issues.