Endo - Stuff Missed Flashcards
Side effect of thialidozines
Fluid retention, weight gain and edema
Side effect of metformin therapy
Lactic acidosis -
** don’t use in patients with abnormal renal function, liver function, CHF, alcoholism, and sepsis
Thialidozines
bind to PPAR-gamma to improve insulin resistance
- may take days to weeks to work
Congenital hypothyroidism
presents soon after birth with hypotonia, poor feeding, jaundice, macroglossia, constipation and umbilical hernia
- diagnosis early to prevent mental retardation
Pulsatile administration of GnRH analogs has what effect?
It has an AGONIST effect and stimulates LH and FSH release
Continuous adminsitration of GnRH analogs have what effect?
It has an ANTAGONIST effect and suppresses LH and FSH release
Anovulation
- common cause of infertility
- can be treated by administering menotropin (human menopausal gonadotropin analog) that acts like FSH and leads to formation of dominant follicle
- Ovulation is induced by large dose of hCG which stimulates LH surge
FSH
- stimulates dominant follicle to form in one of ocaries
- stimulates estrogen production from ovaries
- as follicle expands, there is a rise in estrogen
- In follicular phase, estrogen has positive feedback on LH leading to LH surge which eventually causes rupture of follicle
Anastrozole
selective aromatase inhibitor
- thus less conversion of androgens into estrogens
- suppress estrogen to postmenopausal levels
- in treatment of metastatic breast cancer, aromatase inhibitors are equivalent or superior to tamoxifen
Ketoconazole
- selective aromatase inhibitor
- antifungal agent that decreases androgen synthesis
2 y.o. girl has ambiguous genetailia. Has clitoral enlargement and partial fusion of labioscrotal folds - has high BO - hypokalemic - is 46, XX Likely diagnosis?
11-B hydroxylase deficiency
- less cortisol production
- less aldosterone production (hypertension and hypokalemia)
- more testosterone production (virilization of female)
-
11-B hydroxylase deficiency
- results in excessive adrenal androgen and mineralcorticoids (but NO ALDOSTERONE)
- females are born with ambiguous genitalia
- develop hypertension because of weak mineralcorticoid excess (not as good as aldosterone but good enough)
- hypokalemia
17-alpha hydroxylase deficiency
- results in:
- less cortisol
- less teststerone
- Females are born with normal genitalia
- Males are born UNDERVIRILIZED (less testosterone)
- affected don’t undergo puberty (no sex hormones)
- develop HYPERtension and hypokalemia (mineralcorticoid excess)
21 hydroxylase defiency
- most common cause of adrenal hyperplasia
- less cortisol
- less mineralcorticoids
- more testosterone
- Females have ambiguous genitalia (due to testosterone excess)
- HYPOtension and HYPERkalemia
Finasteride
5-alpha reductase inhibitor
- suppresses peripheral conversion of testosterone to DHT
- used in BPH and androgenetic alopecia
Nephrogenic DI
caused by lack of response to ADH
- can be treated by hydrochlorothiazide
Primary polydipsia
- excessive pathological water drinking
- psych disorder no underlying medical etiology
- water deprivation test will show increase in urine osmolality
- low serum sodium levels
- restriction of water normalizes urine osmolality
Neurogenic DI
- due to decreased production of ADH in posterior pituitary
- decreased urine osmolality with dehydration
- increased urine osmolality with ADH
Nephrogenic DI
- due to decreased responsiveness of collecting tubules to ADH
- decreased urine osmolality with dehydration
- decreased urine osmolality with ADH
Thiazolidinediones (TZDs)`
- bind to peroxisome proliferator activated receptor-gamma (PPAR-gamma) - a transcript regulator involved in glucose and lipid metabolism
- takes days to work
- lowers glucose by decreasing insulin resistance
- increaeses expression of adiponectin gene
Leptin
- secreted by fat cells
- responsible for appetitie suppression and decreased insulin resistance
How do prolactinomas leads to osteoporosis?
- High levels of prolactin decrease GnRH
- Less GnRH leads to less estrogen
- Less estrogen means loss in bone density as estrogen is protective against osteoporosis
MEN1
3Ps
- Parathyroidism
- Peptic ulcer
- Pituitary adenoma
Men2A
2s
- Pheochromocytomas
- Pituitary adenoma
- Medullary thyroid carcinomas
Men 2B
- Medullary thyroid Carcinoma
- Pheochromocytoma
- Oral/intestinal ganglioneuromatosis (associated with marfanoid habitus)
Medullary Thyroid Carcinoma
- usally from parafollicular C cells
- produce calcitonin, sheets of cells in amyloid strom
- associated with MEN2A and MEN 2B
Carcinoid syndrome
caused by neuroendocrine cells esp. metastatic bowel caner tumors
- secrete high levels of 5-HT
- not seen if tumor is limited to GI tract because liver processes
- presents with recurrent flushing, asthmatic wheezing, and right side valvular disease
Carcinoid syndrome Findings and Treatment
- Recurrent flushing, asthmastic wheezing, right-sided valvular disease
- 5-HIAA inurine
- Niacin deficiency
Tx: Somatostain analog (e.g. octreotide)
Conditions associated with excess growth hormone. In children? in adults?
In children: Gigantism - excess growth hormone before closure of epiphyses
In adults: Acromegaly - excess growth hormone after closure of epiphyses
Growth hormone
- increases linear growth by stimulating production of IGF-1 from liver
- defective growth hormone receptors leads to decrease in linear growth
Laron dwarfism
- due to decrease in linear growth
- characterized by high serum growth hormone levels with low IGF-1
Acute effects of corticosteroids
- Increased neutrophil count
- Decreased lymphocyte, monocyte, basophil, and eosinophil counts
- Increase in neutrophil due to demargination of neutrophils previously attached to vessel walls
Which hormone needs to be monitored in amiodarone therapy?
TSH
- Amiodarone (40% iodine) can lead to hypothyroidism
- Amiodarone induced hypothyroidism is treated with levothyroxine
Amiodarone
class III anti-arrhythmic used to suppress cardiac conduction -
Amiodarone side effects
- Thyroid dysfunction
- Corneal microdepsots
- Blue-gray skin discoloration
- Drug related hepatitis
- Pulmonary fibrosis (rare but life threatening)
Glucocorticoiids
- predominatwly carabolic, causing muscle weakness, skin thinning, impaired wound healing, osteoporosis, and immunosuppression
- increase liver protein synthesis, specifically ones involved in gluconeogenesis and glyconegenesis
Hydrochlorothiazide
- acts on distal tubules (blocks Na/Cl)
- causes HYPERgluc -
- Hyperglycemia
- Hyperlipidemia
- Hyperuricemia
- Hypercalcemia
Risperodine and amenorrhea
- Risperidone (atypical anti-psychotic) is associated with hyperprolactinemia
- Riperiodone suppresses dopamine. Dopamine suppresses prolactin
- More prolactin means less GnRH which means less FSH and less LH thus no menstruation
Mechanism of B-blockers in thyrotoxicosis
- Decrease in effect of sympathetic adrenegic impulses reaching target orens
- Decrease in peripheral conversion of T4 to T3
teen girl presents as thin with downy hair
- presents with inadequate diet and regular excercises
- asks about weight loss advice
Likely diagnosis?
Anorexia nervosa - often presents as decreased LH, FSH, estriadiol, and estrone
- hypogonadotropic amenorrhea
- often presents with downy
Long term use of glucocorticoids leads to what effect on adrenal glands
Long term glucocorticoids suppress HPA axis (by decreasing ACTH release)
- Leads to bilateral adrenocortical atrohy
What occurs if patient suddenly stops taking doses of corticosteroids?
Adrenal crisis
Glucagon
- increases serum glucose by increased production of glucose from liver
- stimulates insulin secretion from pancreas
- has little effect on skeletal muscle
Addison’s disease
Chronic primary adrenal insufficiency due to adrenal atrophy OR
destruction by disease (e.g. autoimmune, TB, metasstasis)
- aldosterone deficiency and cortisol
- HYPOtension
- HYPERkalemia
- skin HYPOpigmentation
Epinepherine (and glucose)
epinepherine increases glucose by various mechanisms
- increased glycogenolysis and gluconeogenesis
- decreases glucose uptake in skeletal muscle
- increases alanine release from skeletal muscle for gluconeogenesis in liver
- increases TG breakdown in fat tissue
Propylthiouracil
thionamide medication used for treatment of hyperthyroidism
- decreases formation of thyroid hormone by inhibiting thyroid peroxidase
Potassium iodide
- may prevent thyroid absorption of radioactive iodine isotopes by competitive inhibition
