Tags: Disease.
An inborn error of steroid metabolism is an inborn error of metabolism due to defects in steroid metabolism.A variety of conditions of abnormal steroidogenesis exist due to genetic mutations in the enzymes involved in the process of which include: 1820-Desmolase (P450scc) deficiency: blocks production of all steroid hormones from cholesterol 3β-Hydroxysteroid dehydrogenase type 2 deficiency: impairs progestogen and androgen metabolism; prevents the synthesis of estrogens glucocorticoids and mineralocorticoids; causes androgen deficiency in males and androgen excess in females Combined 17α-hydroxylase/1720-lyase deficiency: impairs progestogen metabolism; prevents androgen estrogen and glucocorticoid synthesis; causes mineralocorticoid excess Isolated 1720-lyase deficiency: prevents androgen and estrogen synthesis 21-Hydroxylase deficiency: prevents glucocorticoid and mineralocorticoid synthesis; causes androgen excess in females 11β-Hydroxylase type 1 deficiency: impairs glucocorticoid and mineralocorticoid metabolism; causes glucocorticoid deficiency and mineralocorticoid excess as well as androgen excess in females 11β-Hydroxylase type 2 deficiency: impairs corticosteroid metabolism; results in excessive mineralocorticoid activity 18-Hydroxylase deficiency: impairs mineralocorticoid metabolism; results in mineralocorticoid deficiency 18-Hydroxylase overactivity: impairs mineralocorticoid metabolism; results in mineralocorticoid excess 17β-Hydroxysteroid dehydrogenase deficiency: impairs androgen and estrogen metabolism; results in androgen deficiency in males and androgen excess and estrogen deficiency in females 5α-Reductase type 2 deficiency: prevents the conversion of testosterone to dihydrotestosterone; causes androgen deficiency in males Aromatase deficiency: prevents estrogen synthesis; causes androgen excess in females Aromatase excess: causes excessive conversion of androgens to estrogens; results in estrogen excess in both sexes and androgen deficiency in malesIn addition several conditions of abnormal steroidogenesis due to genetic mutations in receptors as opposed to enzymes also exist including: Gonadotropin-releasing hormone (GnRH) insensitivity: prevents synthesis of sex steroids by the gonads in both sexes Follicle-stimulating (FSH) hormone insensitivity: prevents synthesis of sex steroids by the gonads in females; merely causes problems with fertility in males Luteinizing hormone (LH) insensitivity: prevents synthesis of sex steroids by the gonads in males; merely causes problems with fertility in females Luteinizing hormone (LH) oversensitivity: causes androgen excess in males resulting in precocious puberty; females are asymptomaticNo activating mutations of the GnRH receptor in humans have been described in the medical literature and only one of the FSH receptor has been described which presented as asymptomatic.
