Isolated 17,20-lyase deficiency: Difference between revisions

Isolated 17,20-lyase deficiency
Synonyms	17,20-desmolase deficiency
Pronounce	N/A
Specialty	N/A
Symptoms	Hypertension, ambiguous genitalia, hypogonadism
Complications	Infertility, adrenal hyperplasia
Onset	Congenital
Duration	Lifelong
Types	N/A
Causes	Mutations in the CYP17A1 gene
Risks	Family history of the condition
Diagnosis	Genetic testing, hormone level testing
Differential diagnosis	Congenital adrenal hyperplasia, androgen insensitivity syndrome
Prevention	N/A
Treatment	Hormone replacement therapy, surgery
Medication	Glucocorticoids, mineralocorticoids
Prognosis	Variable, depending on severity and treatment
Frequency	Rare
Deaths	N/A

Latest revision as of 01:07, 8 April 2025

Editor-In-Chief: Prab R Tumpati, MD
Obesity, Sleep & Internal medicine
Founder, WikiMD Wellnesspedia &
W8MD's medical weight loss NYC, sleep center NYC
Philadelphia medical weight loss and Philadelphia sleep clinics

Isolated 17,20-lyase deficiency is a rare congenital disorder that affects the production of sex steroids due to a defect in the enzyme 17,20-lyase. This enzyme is crucial for the biosynthesis of androgens and estrogens from progestogens.

Pathophysiology[edit]

The enzyme 17,20-lyase, also known as CYP17A1, is responsible for the conversion of pregnenolone and progesterone into their respective 17-hydroxylated products, which are then converted into dehydroepiandrosterone (DHEA) and androstenedione. In isolated 17,20-lyase deficiency, mutations in the CYP17A1 gene impair this conversion, leading to decreased levels of DHEA and androstenedione, and consequently, reduced synthesis of testosterone and estradiol.

Clinical Presentation[edit]

Patients with isolated 17,20-lyase deficiency typically present with ambiguous genitalia or disorder of sex development (DSD) in 46,XY individuals, due to insufficient androgen production. 46,XX individuals may present with delayed puberty, primary amenorrhea, and lack of secondary sexual characteristics.

Diagnosis[edit]

Diagnosis is based on clinical presentation, hormonal assays showing low levels of androgens and estrogens with elevated levels of gonadotropins, and genetic testing confirming mutations in the CYP17A1 gene.

Treatment[edit]

Management of isolated 17,20-lyase deficiency involves hormone replacement therapy to induce and maintain secondary sexual characteristics and to address any associated adrenal insufficiency. Glucocorticoids may be administered to suppress elevated adrenocorticotropic hormone (ACTH) levels.

@@ Line 1: / Line 1: @@
-[[File:Autosomal_recessive_-_en.svg|Autosomal recessive - en|thumb]] '''Isolated 17,20-lyase deficiency''' is a rare [[congenital]] disorder that affects the production of [[sex steroids]] due to a defect in the enzyme 17,20-lyase. This enzyme is crucial for the biosynthesis of [[androgens]] and [[estrogens]] from [[progestogens]].
+{{SI}}
+{{Infobox medical condition
+| name            = Isolated 17,20-lyase deficiency
+| image           = [[File:Autosomal_recessive_-_en.svg|200px]]
+| caption         = Isolated 17,20-lyase deficiency is inherited in an [[autosomal recessive]] pattern.
+| synonyms        = 17,20-desmolase deficiency
+| field           = [[Endocrinology]]
+| symptoms        = [[Hypertension]], [[ambiguous genitalia]], [[hypogonadism]]
+| complications   = [[Infertility]], [[adrenal hyperplasia]]
+| onset           = [[Congenital]]
+| duration        = Lifelong
+| causes          = Mutations in the [[CYP17A1]] gene
+| risks           = Family history of the condition
+| diagnosis       = [[Genetic testing]], [[hormone level testing]]
+| differential    = [[Congenital adrenal hyperplasia]], [[androgen insensitivity syndrome]]
+| treatment       = [[Hormone replacement therapy]], [[surgery]]
+| medication      = [[Glucocorticoids]], [[mineralocorticoids]]
+| frequency       = Rare
+| prognosis       = Variable, depending on severity and treatment
+}}
+'''Isolated 17,20-lyase deficiency''' is a rare [[congenital]] disorder that affects the production of [[sex steroids]] due to a defect in the enzyme 17,20-lyase. This enzyme is crucial for the biosynthesis of [[androgens]] and [[estrogens]] from [[progestogens]].
 == Pathophysiology ==
 The enzyme 17,20-lyase, also known as [[CYP17A1]], is responsible for the conversion of [[pregnenolone]] and [[progesterone]] into their respective 17-hydroxylated products, which are then converted into [[dehydroepiandrosterone]] (DHEA) and [[androstenedione]]. In isolated 17,20-lyase deficiency, mutations in the [[CYP17A1]] gene impair this conversion, leading to decreased levels of DHEA and androstenedione, and consequently, reduced synthesis of [[testosterone]] and [[estradiol]].
 == Clinical Presentation ==
 Patients with isolated 17,20-lyase deficiency typically present with ambiguous genitalia or [[disorder of sex development]] (DSD) in [[46,XY]] individuals, due to insufficient androgen production. [[46,XX]] individuals may present with delayed puberty, primary [[amenorrhea]], and lack of secondary sexual characteristics.
 == Diagnosis ==
 Diagnosis is based on clinical presentation, hormonal assays showing low levels of androgens and estrogens with elevated levels of [[gonadotropins]], and genetic testing confirming mutations in the [[CYP17A1]] gene.
 == Treatment ==
 Management of isolated 17,20-lyase deficiency involves hormone replacement therapy to induce and maintain secondary sexual characteristics and to address any associated [[adrenal insufficiency]]. [[Glucocorticoids]] may be administered to suppress elevated [[adrenocorticotropic hormone]] (ACTH) levels.
+== See also ==
-== Related Pages ==
 * [[Congenital adrenal hyperplasia]]
 * [[Disorder of sex development]]
@@ Line 20: / Line 35: @@
 * [[Estrogen]]
 * [[Hormone replacement therapy]]
 == See Also ==
 * [[Endocrinology]]
 * [[Genetic disorder]]
 * [[Steroidogenesis]]
 [[Category:Genetic disorders]]
 [[Category:Endocrinology]]
 [[Category:Congenital disorders]]
 [[Category:Sexual health]]
 {{Endocrine system diseases}}
 {{medicine-stub}}