What causes testicular feminization?
Genetic male that phenotypically looks female due to androgen insensitivity
- Deficiency of 5a-reductase is most common cause
--> Absence of Testosterone and Mullerian inhibiting Substance permits female pattern to develop although abdominal testes will be present
--> cannot activate testosterone, therefore, external virilization and male sexual maturation at puberty do not occur
What causes congenital adrenal hyperplasia?
--> Aldosterone and cortisol cannot be produced, due to hydroxylase deficiency. therefore, no ACTH negative biofeedback occurs resulting in increased androgen production
--> Results in masculinity of genetic females
What is gonadarche?
Activation of gonadal functions
-> Cause: GnRH driven pituitary LH/FSH secretion
What is Thelarche?
- Cause: ovarian estrogen
What is adrenarche?
Activation of adrenal androgen secretion causing the appearance of pubic and axillary hair
- includes changels in sweat glands and composition of sweat leading to adult body odor
- Cause: uncertain - ot ACTH or gonadotropin mediated
What is peripherial vs central precocious puberty?
Peripheral: caused by source of androgens outside of brain hormone release
Central: Due to increased release of LH by pituitary gland
How does testing LH help determine peripheral vs central precocious puberty?
Normal = rules out "precocious" puberty
interpretation: normal development for this child
High = central precocious puberty
treatment: suppression of HPG axis with super active GnRH analogs
Low = peripheral precocious puberty
treatment: identify source of sex steroids (adrenal, Rx, diet) and treat accordingly
What are causes of central precocious puberty?
- Tumors (astrocytomas, gliomas, germ cell tumors secreting HCG)
- Hypothalamic hamartomas
- Acquired CNS injury caused by inflammation, surgery, trauma, radiation therapy, or abcess
- Congenital anomalies (i.e. hydrocephalus, arachnoid cysts, suprasellar cysts)
What are the components of the adenohypophysis?
AKA anterior lobe of pituitary
Pars distalis (pars anterior)
What are the components of teh neurohypophysis?
AKA posterior lobe of pituitary
Pars nervosa (infundibular process)
Infundibulum (neural stalk)