Problem Set Highlights Flashcards
SGPSS16 Case 1:
Woman has amenorrhea at age 13. She has galactorrhea at age 16. Vision normal.
Take home: PROLACTINOMA.
Prolactin negatively regulates GnRH from POA, thus amenorrhea. Prolactin promotes lactation at breasts, thus galactorrhea. Consider bromocriptine which is a dopamine agonist. Tonic dopamine negatively regulates prolactin release.
SGPSS16 Case 2:
Woman goes into hypovolemic shock post-delivery. She can’t nurse the child, and her breasts and genitals atrophy. Loss of pubic hair.
Sheehan’s syndrome.
Anterior pituitary is infarcted. No prolactin - can't nurse No ACTH No TSH - bradycardia/hypothermia No LH/FSH - atrophy of 2ndary sex
SGPSS16 Case 3:
A 48-year-old man. Impotence. Diminished facial hair growth. Abnormally fast bone growth (feet, teeth). Face bigger. Enlarged tongue. Tingling in joints. Vision loss in both lateral (temporal) fields. ENLARGED LIVER. High IGF-1 levels. GH did not respond to negative regulation by glucose. MRI shows pituitary tumor.
Acromegaly due to GH-secreting pituitary tumor.
Key points: GH promotes IGF-1 release IN THE LIVER. Tingling is due to neuron compression at joints. Hyperglycemia normally suppresses GH release, but tumors don’t follow the law. Somatostatin also normally suppresses GH release.
Side effects of tumor compression: impotence and less facial hair (less LH/FSH), loss of vision
SGPSS 17: Case 1
49 yo woman. Glucose in urine. Hx of proximal weakness, fatigue, and weight gain over the past year. Easily bruised. Period’s ceased 6 months earlier, with concurrent facial hair growth. Physical exam: round face, fat in torso not arms. facial hair. purple striae on abdomen. High systolic BP (160/105), normal HR (78).
Lab: high fasting glucose 140 mg/dl
Cushing’s disease.
- HTN from overflow activation of excess GC onto mineracorticoid receptors.
- High BG from excess gluconeogenesis.
- Weakness from catabolic effects (proteolysis) of GC.
Differential Diagnosis:
- Pituitary tumor: try dexamethasone challenge
- Ectopic tumor
- Iatrogenic: atrophy of Z. fasc
- Primary adrenal: low ACTH, adrenal hyperplasia.
SGPSS 17: Case 2
34 yo woman. Tan skin, unrelated to sun. Depressed. Palpitation, tremor, sweating, and light- headedness after fast.
Physical Examination: hyper pigmentation over pressure points (knuckle or elbow), and bluish-black patches on mucous membranes.
Postural hypotension!
Sitting: 95/70 mmHg), 80/min
Standing: 60/40 mmHg, 130/min. Blood glucose: 46 mg/100 ml.
Addison’s Disease.
Adrenal insufficiency - can’t make enough GC and MC. Low GC lifts the negative feedback on hypothalamic CRH stimulation of anterior pituitary, which pituitary POMC, which is cleaved into ACTH and MSH. Thus:
High ACTH - no adrenal hyperplasia because nothing to stimulate…
High MSH - hyperpigmentation
Low aldosterone: hyponatremia, hyperkalemia, salt cravings
SGPSS 17: case 3
A 50-year-old housewife complains of progressive weight gain of 20 pounds in 1 year, fatigue, loss of memory, slow speech, deepening of her voice, dry skin, constipation, cold intolerance, and ataxia.
Physical Examination: Vital signs include a temperature 96.8°F, pulse 58/minute and regular, BP 140/90. She speaks slowly and has a puffy face, with pale, cool, dry, thick skin and a yellow tint. The thyroid gland is not palpable. Deep tendon reflexes are normal in intensity but slow to relax.
Hypothyroid: Low T3 levels
Cognitive symptoms: loss of memory
Metabolic symptoms: weight gain due to low BMR, fatigue (pallor due to anemia), cold intolerance, ataxia, puffy face (myxedema), yellow skin (carotenemia)
Cardiac symptoms: low hear rate
Do TRH challenge to determine what level of deficiency. Thyroxine treatment.
SGPSS17 Case 4:
A 25-year-old nurse complains of nervousness, mood swings, weakness, and palpitations with exertion for the past 6 months. Sweating and heat intolerance. Doubled food intake, same weight. Regular menstrual periods, less bleeding though.
Pulse is 92/minute and BP is 130/60. Bounding cardiac apical impulse, a pulmonic flow murmur, muscle weakness. Goiter, no nodules, with a bruit and a thrill.
Hyperthyroidism. Too much T3 increases BMR.
Primary: High T3, Low TSH
Secondary: High T3, High TSH
Graves disease: auto-antibody stimulates TSH receptor. This is primary.
Tests: Measure TSH and T3 levels. Request radioactive iodine scan. Hot spots indicate nodules. Equal symmetrical uptake indicates diffuse goiter.
Treatment: Thyroidectomy, or inhibit TPO via methimazole or PTU. Beta-blockers to restore heart function (too much T3 can cause arrhythmia)
SGPSS 18 Case 1
A 46-year woman. Fatigue. Constipation. Hx of kidney stones and mild hypercalcemia. No Hx of wt loss, bone pain, abdominal masses, or headache.
Physical Examination: Blood pressure 150/92 and pulse 84/minute and regular. Pt is well developed, well nourished, and well hydrated. Seems normal.
Lab: 12.2 mg/dL Calcium (9-10.3 normal)
Hypercalcemia.
There are many reasons for hypercalcemia. It could be primary hyperparathyroidism (measure PTH) or it can be PTHrP from a tumor. Other causes include lithium, high dietary calcium and VitD.
Treatment: calcitonin or bisphosphate therapy to suppress osteoclast activity.
SGPSS 18 Case 2
A 48-year old woman has hypocalcemia on routine testing. Leg cramps and paresthesia. Thyroidectomy patient, on synthroid. Blood pressure 124/78 and pulse 74/minute and regular. Abnormalities include bilateral cataracts and spasm of her hand during blood pressure testing.
Iatrogenic Hypocalcemia.
Cataracts only seen in chronic patients.
o Need to measure albumin, ionized calcium, intact PTH.
o Serum phosphate should be high due to low PTH.
o Rule out renal disease – measure magnesium, potassium .
Give patient oral Ca and calcitriol
SGPSS 18 Case 3
Hypocalcemia 18-year old woman with cataracts and mild mental retardation. Paresthesia, and Hx of seizures. Blood pressure 128/72 and pulse of 84/minute and regular. Abnormalities include bilateral cataracts, spasm of her hand during blood pressure testing, and spasm of the muscles of one side of the face on tapping the cheek. The 4th metacarpals and metatarsals are short.
Sx look like regular hypoparathyroidism, but short metatarsal/metacarpal: think
Pseudohypoparathyroidism
Defect in the PTH1R receptor (a GPCR)
SGPSS 19: Case 1
History: A 15-year-old boy w/ delayed puberty. No male secondary sexual characteristics. Mental ok. No erection, no sexual interest, and has never masturbated. Normal height. CANNOT SMELL foods. No Hx of headaches, seizures, impaired peripheral vision or rhinorrhea.
BP: 120/80 and pulse 80/minute and regular. Looks young. Sparse axillary/pubic hair. No facial or other body hair, no temporal hair recession, slight decrease in muscle mass for age, high-pitched voice, and no gynecomastia. Repaired cleft palate. Small testes and phallus. No hypospadias.
Kallman’s syndrome.
No GnRH, so no LH to Leydig cells to promote testosterone secretion, and no FSH to follicular cells to promote spermatogenesis.
The lack of testosterone means lack of secondary sex characteristics at puberty. He has testicles because SRY and TDF.
Apply GnRH to distinguish between a. pituitary or hypothalamic failure.
SGPSS 19: Case 2
23-year-old male has gynecomastia (starting at age 12) and incomplete development of secondary sexual characteristics. He presently has a sparse beard, which requires shaving 1/week. Little penis growth, libido, and sexual activity in puberty. BP 126/72 and pulse 74/minute and regular. His weight is 220 lbs., height 74” with an arm span of 71”, lower segment 39”, and upper segment 35”. The penis is small with the urethra exiting the glans in the normal position. Both testes are in the scrotum but small and firm.
XXY Klinefelters syndrome
Phenotypic hallmarks: gynecomastia (from elevated E2:T ratio), small/firm testes and scrotum.
High LH/FSH, Low T. Fibrosis of seminiferous tubules, prevents transport of T from Leydig to Sertoli.
This patient needs T therapy, aromatase inhibitors, and surgical removal of breast tissue.
SGPSS 19: Case 3
An 18-year-old woman is referred for evaluation of primary amenorrhea (never having menstruated). Her breasts developed normally but she failed to develop any axillary or pubic hair. BP 124/74 and pulse is 82/minute and regular. Her height is 65” and her arm span is 62”. Normal external genitalia, with no clitoromegaly. Shallow vagina ending in a blind pouch, no uterus is seen or palpated. High serum T and LH, than male/female. E2 higher than male, normal for female.
This is an XY genotypic male with androgen receptor deficiency, with an underdeveloped female phenotype.
SRY promoted testes development, which secreted AMF from the sertoli cells to diminish mullerian ducts - hence lack of uterus and complete vagina. However, since androgen receptors are nonfunctional, Wollfian duct system is absent too! In the absence of effective T, the patient’s external genitalia followed the default female program.
SGPSS 20: Case 1
A 16-year-old girl consults because of short stature (4 ft, 10 in.), lack of breast development, and primary amenorrhea. Normal delivery at birth, but widened neck and edema of hands/feet. The patient had an uncomplicated infancy and childhood. Siblings normal. Normal vital signs, webbing of the neck, high-arched palate, low posterior hairline, low-set ears, cubitus valgus, and shortening of the fourth metacarpal bones. Karyotype is 45,X. Laparoscopy revealed ovarian streaks bilaterally.
Turner’s Syndrome XO
Lack of ovary results from lack of 2nd X in utero (critical time when both X’s are needed). Lack of ovary resulting in lack of E2, so no negative inhibition on hypothalamus (high GnRH) and anterior pituitary (high LH/FSH).
Internal and external genitalia should develop normally since no Testes around to secrete AMH.
You should give this pt. E2 therapy after growth hormone, since E2 closes epiphyseal plates.
Infertile.
SGPSS 20: Case 2
A 34 year old woman (G0P0) presents to the clinic with complaints of irregular periods and new hair growth. No drug or family Hx indicators of hirsutism. Excessive daytime fatigue. Sleep apnea. Obese. No indicators of acromegaly or Cushing’s syndrome. Modest acne on face and back. Loss of scalp hair in a male pattern.
Polycystic ovarian syndrome. Look for enlarged ovaries, and use ultrasound to check for cysts. These cysts secrete a lot of androgens. Prescribe metformin and/or clomiphene.
