Endocrinology Flashcards
Most common cause of Hyperparathyroid?
Parathyroid adenoma
Primary Hyperparathyroidism: defn and symptoms
Elevated Calcium due to high PTH
Sxs: Constipation, Dehydration, abdominal pain, bone pain, Kidney stones, arrhythmias
“Bones, stones, abdominal groans, and psychic overtones”
Most common cause of secondary hyperparathyroidism? What is secondary?
Chronic Renal Disease
PTH is high (as in primary) BUT its because calcium is low
Hyperparathyroidism Diagnosis/findings
Increased PTH confirms dx
Hallmark: Hypercalcemia (If hypocalcemia–renal failure disorder, secondary)
EKG: Prolonged PR interval, Shortened QT interval; “Too much too soon, too little too late”
What is a common cause of hypoparathyroidism?
Thyroidectomy
What are the sxs of hypoparathyroidism?
Sxs are always those of HYPOCALCEMIA:
positive Chvostek’s sign, Positive Trousseau’s phenomenon
Cataracts, Teeth/nail defects, tetany, circumoral tingling
Treatment of Hypoparathyroidism?
Calcium and Vitamin D supplementation for life
Acute attacks: IV calcium gluconate
Differentiate between the three Thyroiditis: Acute, subacute, and Chronic lymphocytic
Acute (Suppurative): Pyogenic bacteria, very painful, tender red thyroid; Tx: abx and surgical drainage
Subacute: (de Quervain’s) Viral, Painful enlarged thryoid, low radioactive iodide uptake, Tx: ASA for pain and inflammation
Chronic lymphocytic: Fatigue, dry eyes, dry mouth; Diffusely enlarged firm nodular thyroid; Tx: Levothyroxine
what is the most common type of thyroid cancer?
Papillary Carcinoma
What is the most aggressive thyroid cancer?
Anaplastic
Thyroid Cancer diagnostics
Elevated serum Thyroglobulin: Metastatic papillary and follicular
Fine needle biopsy: Test of choice for initial evaluation of a thyroid nodule; reliable for all types of the cancer except Follicular!—>Incisional biopsy
Radionuclide scan: Performed if the FNA biopsy is indeterminate. COld nodules–>cancer, Hot nodules benign (still only 20% of cold are malignant)
What sxs are associated with medullary thyroid cancer?
flushing, diarrhea, fatigue, and cushing’s syndrome
Which thyroid disease is associated with excess dietary idodine supplementation and exposure to head/neck radiation during childhood?
Hashimotos thyroiditis
Most common cause of Corticoadrenal insufficiency?
Autoimmune destruction of the adrenal cortex-Addison’s Disease
What are the sxs of Addison’s Crisis? Tx?
Hypotension, Acute pain, vomiting, Diarrhea;
Tx: IV saline, Glucose, glucocorticoids
Diagnostic/Labs of Addison’s dz
labs: hyperkalemia, Hyponatremia, hypoglycemia, hypercalcemia, Low Cortisol, High ACTH
Cosyntropin stimulation–diagnostic
- Cortisol <20 mg/dL=positive
Low AM serum cortisol level with high ACTH level–>dx
(High ACTH, bc cortisol which inhibits ACTH is low)
Treatment of Addisons
DOC=hydrocortisone
Fludrocortisone may be added if inadequate salt-retaining effect
What is the most common cause of Cushing’s syndrome?
Cushing’s Disese (ACTH secreting pituitary tumor)
What is the normal function of ACTH
stimulates production of Cortisol
HOw do you diagnose Cushings syndrome? labs?
- Free urine cortisol >125 mg/dL in 24 hours
-
Dexamethasone suppression test
- Plasma cortisol >10 ug/dL
- Plasma ACTH <20 pg/mL
- suggests adrenal tumor
- MRI to identify pituitary tumor
- Corticotrophin-releasing hormone
- separates ACTH-dependent from ACTH independent hypercortisolism
Labs: Hyperglycemia, hypokalemia
How do you treat Cushings?
- Adrenal Inhibitors: Metyrapone or ketaconazole suppress hypercortisolism
- Resect tumor if cushings dz
What is the most common cause of Acromegaly?
Pituitary Adenoma
How do you dx Acromegaly/Gigantism?
- elevated HGH-won’t suppress with hyperglycemia (as it normally does
- MRI: to visualize possible pituitary tumor
- Radiography: enlarged sella turcica
Treatment of Gigantism
- Surgery: Transnasal transsphenoidal
- If surgery fails–>Dopamine agonist->shrink tumors
- Somatostatin analogs-for persistent dz
Diabetes Insipidus: Describe the two types and common causes of each
- Central (neurogenic)
- Posterior pituitary not making ADH (vasopressin); may present after head trauma
- Nephrogenic
- Adequate ADH being produced but kidneys are not responding (renal receptors not working)
- Cause: Lithium toxicity, chronic renal dz, hypercalcemia
Sxs of Diabetes Insipidus
Increased thirst, Large volume polyuria
Diagnostics of Diabetes Insipidus
- 24 hour urine collection with vasopressin Challenge test
- Initial: Low urine osmolality (lots of dilute urine)
- H20 deprivation: Normal person stops urinating without water. Person with DI will continue to urinate large amounts of dilute urine
- Give ADH (vasopressin challenge test): Differentiates between Nephrogenic and Central
- Central: Serum osmolality/urine osmality will improve with DDAVP
- Nephrogenic: No improvement
Treatment of Diabetes Insipidus
Central: Desmopressin Acetate (Nasal)–Synthetic ADH
Nephrogenic: HCTZ, Indomethacin
SIADH: what is it? Most common cause? labs? Tx?
Too much ADH
Most common cause: Chronic space occupying lung lesion (tumor, abscess, Tb)
Labs: Hypnatremia (Seizures, coma, arrhythmia)
Tx: Fluid restriction, Give saline if severe
Initial lab for Turner Syndrome?
Elevated FSH
What produces ADH?
Posterior Pituitary
What produces TSH?
Anterior Pituitary
How does the dexamethasone suppression test work? What does it help diagnose?
Cushing’s Disease
Give dexamethasone to Pt–In a normal pt should shut off ACTH production and decrease Cortisol production. But if tumor exists that producing ACTH on its own, You will still have high cortisol levels.
What gland produces corticosteroids? What gland first sends signal to this gland? How?
Where does secondary adrenal insufficiency start fucking up in this cycle?
Pituitary gland sends signal to Adrenal gland (VIA ACTH) to produce corticosteroids
In secondary adrenal insufficiency–>Pituitary gland stops sending signal
In Primary–>The adrenal gland stops producing corticosteroids (despite plenty of ACTH)
What test is diagnositic in Addison’s disease?
Cosyntropin test
