Disorders of Sexual Development Flashcards
What is the karyotype of a patient with Klinefelter syndrome?
47,XXY
Detail the body habitus of a male with Klinefelter syndrome.
Testicular atrophy Tall Long extremities Gynecomastia Female hair distribution
What are the LH and FSH levels of a patient with Klinefelter syndrome?
Increased- lack inhibin and testosterone
What is the karyotype of a patient with Turner syndrome.
45,XO
Detail common clinical findings associated with Turner syndrome.
Shield chest Webbed neck (lymphatic defects) Bicuspid aortic calve Preductal coarctation (femoral pulse is less than brachial pulse) Horseshoe kidney
What is the most common cause of primary amenorrhea?
Turner syndrome
What are the LH and FSH levels of a patient with Turner syndrome?
Increased- decreased estrogen
Detail the sexual development of an individual with androgen insensitivity syndrome.
Female external genitalia with a short vagina
Absence of Mullerian structures (due to production of AMH from testes)
Lack of Wolffian structures
Detail the lab findings for T/LH in a patient with androgen insensitivity syndrome.
High T
High LH
Detail the lab findings for T/LH in a patient with a testosterone secreting tumor or exogenous steroid use.
High T
Low LH
Detail the lab findings for T/LH in a patient with primary hypogonadism.
Low T
High LH
Detail the lab findings for T/LH in a patient with hypogonadotropic hypogonadism.
Low T
Low LH
Detail the phenotype of a 46XX female with aromatase deficiency.
Masculinization of infants (ambiguous genitalia)
Mother may present with virilization (fetal androgens cross the placenta)
Do patients with androgen insensitivity have testes?
Yes, must be removed to prevent malignancy
What is Kallmann syndrome?
Form of hypogonadotrophic hypogonadism
Results from defective migration of GnRH cells and formation of olfactory bulb
Low sperm counts in males
Amenorrhea in females
What is the most common DSD in a 46XX fetus?
21-hydroxylase deficiency
Detail the presentation of a XX patient with 21-hydroxylase deficiency.
Salt wasting (infant) Precocious puberty (childhood) Virilization (note, presentation depends on degree of enzyme deficiency)
What CAH causes salt retention?
17α-hydroxylase
11β-hydroxylase
What is the phenotype of a 46XX patient with 11β-hydroxylase deficiency?
Virilization
What is the phenotype of a 46XY patient with 17α-hydroxylase deficiency?
Ambiguous genitalia
Undescended testes
What is the phenotype of a 46XX patient with 17α-hydroxylase deficiency?
Present with lack of secondary sexual characteristics at puberty
All CAH are characterized by what change in the adrenal glands?
Enlargement- increased ACTH due to lack of cortisol
Contrast gonadarche and adrenarche.
Gonadarche- re-emergence of hypothalamic GnRH secretion which stimulates gonadotropes to secrete FSH and LH
Adrenarche- maturation of adrenal gland and production of adrenal androgens
What is the first physical sign of puberty in boys and girls?
Boys- testicular enlargement
Girls- breast bud development
What is the normal age on onset of puberty in boys?
9-14
What is the normal age of onset of puberty in girls?
Caucasian- 8-13
African-American/Hispanics- 1 year earlier
Delayed puberty is defined as the lack of onset or lack of normal progression of puberty. What physical findings in boys is associated with delayed puberty?
No testicular enlargement by age 14
Delayed puberty is defined as the lack of onset or lack of normal progression of puberty. What physical findings in girls is associated with delayed puberty?
No breast development by age 13
No menses 4 years after pubertal onset
No menses by age 16
The approach to delayed puberty is to categorize based on gonadotropin status. Elevated gonadotropins (hypergonadotropic hypogonadism) indicate primary gonadal failure, and low gonadotropins (hypogonadotropic hypogonadism) indicate hypothalamic or pituitary immaturity or dysfunction. What is the most common cause of delayed puberty associated with low gonadotropins?
Constitutional growth delay (late bloomers)
When can the diagnosis of precocious puberty be made?
When puberty begins before defined lower age limits
Complete precocious puberty is defined by early onset, and progression, of pubertal development. What can happen in children with regards to their height in this situation?
Growth plates can close early- short stature
Precocious puberty occurs more commonly in girls but the majority of affected girls will have no identifiable abnormality (idiopathic). The prevalence of precocious puberty in boys is significantly lower, but 50% of affected boys will have what type of lesion?
CNS lesion- central precocious puberty
What test can be ordered to distinguish between central and peripheral precocious puberty?
GnRH stimulation test
Pubertal response = central
Prepubertal response = peripheral
How can central precocious puberty be treated?
GnRH analog (leuprolide)
