Growth and Pubertal Development (Pesce) Flashcards
what are the 4 primary hormones secreted by the hypothalamus?
GnRH, GHRH, CRH, TRH (also somatostatin and dopamine)
all of the folllowing are true regarding growth factors EXCEPT:
A. Insulin like growth factors (IGF-1 and IGF-2) are peptide hormones made in the liver, kidney, muscle, cartilage and bone
B. IGF-1 is more closely related to GH secretion
C. IGF-1 acts through a receptor tyrosine kinase structurally related to the insulin receptor
D. The main difference between IGF-1 and IGF-2 is that IGF-2 is more likely to cause hyperglycemia
E. IGF-2 binds to the IGF-1 receptor; however, preferentially binds to the IGF-2 receptor, which lacks tyrosine kinase domain and does not autophosphorylate
D. IGF-2 is similar to IGF-1 but is less dependent on GH and causes hypoglycemia
If a patient has a low T4 and normal TSH, what is the likely diagnosis?
either secondary or tertiary hypothyroidism - the problem is at the hypothalamic or pituitary level
What tests would you order in a patient who was exposed to radiation in whom you suspect secondary or tertiary hypothyroidism?
your should order TSH AND T3/T4
All of these are effects of thyroid hormones on growth and development EXCEPT:
A. Thyroid hormones stimulate endochondral ossification, linear growth, and maturation of growth plates
B. T4 enhances the maturation and activity of chondrocytes in the cartilage growth plate and also stimulates bone remodeling
C. Tooth development, ovarian and teisticular processes, and maturation of the epidermis all depend on thyroid hormone
D. Thyroid hormone inhibits the synthesis and increases the degradation of mucopolysaccharides (glycosaminoglycans) and fibronectin in the connective tissue
E. Thyroid hormones increase pituitary production of growth hormone
B. It is T3 that does this.
What is the likely diagnosis for a patient that presents with high levels of testosterone but suppressed LH/FSH?
Possibly a tumor that is secreting hCG or TSH (which may stimulate the FSH/LH receptors because of its identical alpha subunit), or is just producing testosterone on its own
sex horomones that accelerate bone growth and also accelerate the rate at which the skeleton matures, causing faster fusion of growth plates
estrogen and androgens
All of the following are effects of glucocorticoids on growth EXCEPT:
A. Excess of glucocorticoids inhibit growth by reducing IGF-1 levels
B. Excess of glucocorticoids inhibit growth by blunting the GH response to stimuli
C. Glucocorticoid excess impairs anabolism (causing bone, muscle, subcutaneous tissue wasting)
D. Glucocorticoid excess causes anovulation by inhibiting gonadotropins response to GnRH
A. Usually, IGF-1 levels are in the normal range though the GH response to a stimulus is blunted.
Which of the following is not attributed to secondary growth disorder?
A. Cushing's syndrome B. IUGR C. Malnutrition D. Osteochondrodysplasia E. Rickets
D. This is an example of a primary growth disorder, along with chromosomal abnormalities.
15.5 year old male with lack of growth for two years, gaining weight well. He started puberty at
age 12 years and reports easy bruising and acne, worsening in the last year. No other symptoms. He has
an unremarkable past medical history and family history. Looks younger and has cherubic face. Tanner
stage V and V. Bone age is delayed 2 years. Diagnosis?
Cushing syndrome
14 year old female, normal height earlier in life, decelerated, then grew normally, below the 5th
percentile. She had menses one year ago. Parents are concerned because she is not growing and they
seek a second opinion. She has normal past medical history and family history. Parents are tall. On
exam, she is Tanner Stage III for breasts and pubic hair. Previously obtained evaluation included normal
IGF-1, normal IGFBP-3, normal TSH and free T4 and normal FSH. Bone age is normal (14 years). Diagnosis?
She has Turner syndrome. Not sure how in the world we would ever know this.
*Pesce’s notes: This is a hard diagnosis. This patient either has a genetic condition or a primary condition of
bone affecting her growth as she is shorter than her parents or, she may have idiopathic short stature.
Any female who is short or shorter as compared to genetic potential needs to be screened for Turner
syndrome, as the phenotype is variable. This patient is a mosaic Turner syndrome.
13 year old female who has not been growing at same rate as peers and seems to be slowing
down in growth to parents. Growth charts show height now below the 5th percentile. She is asymptomatic and past medical history is unremarkable. Mother had menarche at 15 years. Father was a late bloomer and received testosterone injections. On exam, she is Tanner I and I for breasts and pubic hair. Bone age is 10 years. Height prediction is normal for mid-parental target height. She has normal IGF-1, IGFBP-3, normal thyroid function studies. Diagnosis?
Constitutional delay of growth and development.
Patient was monitored closely and eventually started spontaneous puberty at 14 years and had menarche at 16 years. She had growth spurt with puberty and caught up to height potential, without intervention.
A 8.5 year old female with history of pubic hair since the age of 5 years. Having worsening acne, reason that prompted mother to seek medical evaluation. No other symptoms. Tall for mid-parental target. Tanner stage I for breasts and Tanner IV for pubic hair. Prominent acne. Advanced bone age at 11 years. Diagnosis?
Late onset congenital adrenal hyperplasia. Patient had a 17 hydroxyprogesterone level which was elevated at 456 ng/dl. ACTH stimulation test confirmed diagnosis. She was treated with hydrocortisone and was able to achieve final height consistent with mid-parental target. Acne improved with treatment and she did not virilize.
A 7 year old female presents with vaginal bleeding and breast development (Tanner stage IV). On review of systems, her mother reports that the patient has been constipated for about 1 year. Her growth chart does not show growth acceleration and her bone age is 1 year delayed. LH is pre-pubertal. What is the most likely diagnosis? What tests would you order to confirm
your diagnosis? Discuss possible mechanism causing this patient’s sexual precocity.
Patient has precocious puberty with delayed bone age and no growth spurt of puberty. LH is suppressed and she does not have pubic hair. She has isosexual precocious puberty with suppressed LH, in view of delayed bone age, she must be making something that stimulates the ovaries as LH/FSH, however, does not
cause advanced bone age despite higher estrogen levels: This child has primary hypothyroidism. The TSH excess is causing the ovaries to make estrogen
nevertheless, she has a delayed bone age and is not growing well due to the severe hypothyroidism. (Hypothyroidism causing precocious puberty AKA as Van
Gyk Grumbach syndrome or “overlap syndrome”). LH, FSH and TSH share the same alpha subunit. It is thought that very high TSH levels stimulate the ovaries, mimicking LH and FSH.
An 8 year old male presents with growth acceleration and testicular enlargement. On examination, he is Tanner stage IV for genitals and III for pubic hair. There is no family history of early puberty. On exam, child also
has multiple café au lait macules and inguinal and axillary freckling. What is the most likely diagnosis? What would you order to confirm the diagnosis? If your diagnosis is confirmed, would you consider ordering additional studies (imaging)? Which one?
The patient has central precocious puberty in male. This child most likely has a brain problem causing the precocious puberty and a brain MRI is needed, with emphasis to the hypothalamus and pituitary gland. Other clues given in the vignette indicate most likely neurofibromatosis.
