Endocrinology Flashcards
Prolactin deficiency – Sx in men & women?
Men – none
Women – cannot lactate after pregnancy
LH & FSH deficiency – Sx in men?
- Won’t make Testosterone or sperm
- Decreased libido
- Decreased axillary, pubic, & body hair
- Erectile dysfunction
- Decreased muscle mass
LH & FSH deficiency – Sx in women?
- Amenorrhea or irregular menses
- Decreased libido
- (decreased axillary/body/pubic hair)
Kallman Syndrome – what is it?
Dec’d FSH & LH from dec’d GnRH
- Anosmia
- Renal agenesis in 50%
Hyponatremia – what are some endocrine causes of this?
- Hypothyroidism
- Isolated glucocorticoid underproduction
(note: K+ not affected in these b/c aldosterone is normal & this excretes K+)
Which do you replace first before starting the other: Cortisone or Thyroxine?
Replace Cortisone before starting Thyroxine
What is Diabetes Insipidus?
ADH deficiency (central) or no effect of ADH on kidney (nephrogenic)
Nephrogenic Diabetes Insipidus – causes?
- Chronic pyelonephritis
- Amyloidosis
- Myeloma
- Sickle cell disease
- Hypercalcemia
- Hypokalemia
- Lithium
Diabetes Insipidus – presentation?
- Extremely high-volume urine
- Excessive thirst resulting in volume depletion & hypernatremia
- Hypernatremia causes Confusion, disorientation, lethargy, & eventually seizures/coma
Diabetes Insipidus – Urine osmolality?
Urine osmolality (& sodium) are both decreased
– Serum osmolality is elevated
How to determine central vs. nephrogenic diabetes insipidus?
Response to Vasopressin
- Central DI: urine volume inc’s & urine osmolality will increase
- Nephrogenic DI: no effect
Acromegaly – Tx?
- Surgery
- Meds:
- - Cabergoline (DA inhibits GH release)
- - Octreotide (Somatostatin inhibits GH release)
- - Pegvisomant (GH receptor antagonist, inhibits IGF release from liver) - Radiotherapy
Hypothyroidism – causes?
- Hashimoto’s Thyroiditis (almost always the cause & acute phase is rarely perceived)
- Dietary deficiency
- Amiodarone
What is the only bodily process that’s not “slowed down” in hypOthyroidism?
Menstrual flow – increased
Acute Hyperthyroidism & “Thyroid Stom” – Tx?
- Propranolol – blocks target organ effect & dec’s conversion of T4 to T3
- Thiourea drugs (Methimazole & Propylthiouracil) – block hormone production
- Iodinated contrast material (Iopanic acid & Ipodate) – dec’s periph conversion & blocks release of existing hormone
- Steroids (hydrocortisone)
- Radioactive iodine – ablates gland for permanent cure
Patient has a Thyroid Nodule – how is it handled?
- Thyroid function tests (TSH & T4)
2. If tests are normal, Biopsy the gland
Hypercalcemia – presentation?
Polyuria, polydipsia, nausea, vomiting, confusion, stupor, lethargy, & constipation
- Short QT syndrome & HTN
- Osteoporosis
- Nephrolithiasis
- Diabetes Insipidus
- Renal insufficiency
Hypercalcemia – Tx?
Saline hydration & high volume
- Bisphosphonates – Pamidronate & Zoledronic acid
Hypercalcemia 2/2 Sarcoidosis – Tx?
Prednisone controls hypercalcemia when it is from sarcoidosis or any granulomatous disease
Hypercalcemia – most common cause?
Primary hyperparathyroidism & Cancer (PTH-rp)
Others: vit D intoxication, Sarcoidosis, Thiazide diuretics, Hyperthyroidism, Metastases to bone & Multiple Myeloma
Hyperparathyroidism – causes?
- Solitary adenoma (80-85%)
- Hyperplasia of all 4 glands (15-20%)
- Parathyroid malignancy (1%)
How to test for bone effects of high PTH?
DEXA densitometry
Note: bone x-ray is not a good test for this
Hypocalcemia – causes?
- Primary hypoparathyroidism 2/2 prior neck surgery (i.e. thyroidectomy) = MC cause
- Hypomagnesemia (Mg necessary for PTH to be released from gland, low Mg leads to inc’d urinary loss of Ca)
- Renal failure – Kidney converts 25-hydroxy-D to more active 1,25-hydroxy-D
- Vitamin D deficiency
Also: Low albumin state, Fat malabsorption, & Genetic disorders
Low vs. High Calcium Sx?
Low Ca = Twitchy & hyperexcitable
High Ca = Lethargic & slow
