Delayed Puberty

Question 1

What is the definition of delayed puberty?

Answer 1

No secondary sex characteristics by age 13 or no menses with secondary sex characteristics by 15
incidence = 3% of adolescents

Question 2

What are the categories of ddx for delayed puberty?

Answer 2

1. Hypogonadotropic hypogonadism (30%)
2. Hypergonadotropic hypogonadism (43%)
3. Eugonadism (26%) includes:
   a) anatomic
   b) Androgen insensitivity syndrome (XY)
   c) chronic anovulation (i.e. PCOS)
   d) constitutional delay

Question 3

What are potential causes of hypogonadotropic hypogonadism?

Answer 3

central (stress, anorexia, exercise), CNS tumour (craniopharyngioma)
GNRH deficiency (Kallman’s)
chronic disease
hyperprolactinoma
hypothyroid
adrenal: (congenital adrenal hyperplasia, Cushing/Addison’s)

Question 4

What are potential causes of hypergonadotropic hypogonadism?

Answer 4

premature ovarian insufficiency, gonadal dysgenesis (Turner’s vs pure gonadal dysgenesis 46XX or 46XY), chemo/rads leading to POI, 17OH-P deficiency, aromatase deficiency, galactosemia,

Question 5

What will you ask on history of someone presenting with delayed puberty?

Answer 5

onset of pubic/axillary hair, any breast development (estrogen present or not), growth spurt?, timing of parental puberty, medical hx (chronic disease), anosmia? (Kallman), meds (domperidone, anti-psychotics, etc), hobbies (elite athlete), height/wt changes

Question 6

What will you look for on physical exam for a pt with delayed puberty?

Answer 6

height, weight, BMI
tanner stage adrenarche, telarche, signs Turner’s (short stature, webbed neck, low hairline, shield chest, widely spaced nipples, shortened 4th metacarpal), thyroid, external pelvic (?qtip/finger r/o outlet obstruction),

Question 7

What investigations will you order for pt with delayed puberty?

Answer 7

FSH (>40 indicates gonadal failure, <10 indicates hypogonadotropic: hypothalamic/pituitary cause –> MRI)
LH, 17OH-P, TSH, PCOS B/W, PRL
karyotype
fragile x testing (DNA analysis of FMR1 gene)
pelvic u/s -r/o mullerian anomaly/outlet obstruction
MRI brain

Question 8

what is the inheritance pattern of fragile x syndrome?

Answer 8

x-linked dominant with incomplete penetrance -CGG repeats
female carriers (50-200 repeats) can have POI (3-4%)
males >200 have varying degrees of MR, autism, large ears, jaws, testes

Question 9

What is Swyer Syndrome and how do these patients present?

Answer 9

46XY

phenotypic female, streak gonads (remove), no breast development, normal uterus and Fallopian tubes

Question 10

What is androgen insensitivity syndrome and how do these patients present?

Answer 10

46XY

phenotypic female, will not respond to testosterone, functional testes, AMH made so no uterus, tubes, or upper vagina