endocrine Flashcards
(180 cards)
1
Q
which test is the most sensitive for pathologic changes in the thyroid?
A
TSH - most important test clinically
2
Q
what does TSH have a log-linear relationship with?
A
T4
3
Q
T or F: TSH is trustworthy in central (pituitary) disease?
A
false
4
Q
which is the prohormone - T3 or T4?
A
T4
5
Q
which has more in circulation, T3 or T4?
A
T4 (99%)
6
Q
T or F: T4 is less sensitive for disease than TSH
A
true
7
Q
formula for free T4 index
A
total T4 x T3 resin uptake
8
Q
mild hypo or hyperthyroidism; no obvious symptoms
A
subclinical disease
9
Q
biochemical definition of subclinical disease
A
TSH abnormal but free T4 (T3) still within normal range
10
Q
what is low T3 syndrome/sick euthyroid syndrome?
A
in any critical illness, thyroid tests decrease (except rT3) probably both central (CNS) and peripheral causes of this. data does NOT support replacement in the ICU
11
Q
normal TSH
A
0.5-5.0
12
Q
normal T4
A
0.8-1.8
13
Q
tests to determine the etiology of the thyrotoxicosis
A
radioactive iodine uptake
radioactive iodine or technecium scan
14
Q
tests to evaluate for structural thyroid disease
A
imaging the thyroid gland - US
15
Q
what is I-123 uptake?
A
day 1 am: ive patient ~300 micro Curies of I-123
day 2 am: measure percent of I-123 that has been “taken up” by the thyroid gland (this is NOT a picture)
normal uptake is 15-35% @ 24 hours
16
Q
is the I-123 test helpful in the evaluation of hypothyroidism?
A
NO
17
Q
when can the I-123 test not be done?
A
when the patient has recently received a dose of iodinated IV contrast
18
Q
what does “low uptake” in the I-123 test suggest?
A
low thyroid gland activity = thyroiditis as cause of thyrotoxicosis
*uptake distinguishes between thyroiditis and the other diagnoses
19
Q
what does normal or High uptake in the I-123 test indicate?
A
favors active gland = Graves or “hot nodules”
20
Q
what does nuclear imaging (scintigraphy) do for thyroid testing?
A
gives the pattern of uptake, answers the question of Graves’ vs. hot nodules
21
Q
when the uptake is low in the I-123 test, should you order a scan?
A
NO - wasteful because nothing to look for on scan
22
Q
how do you treat hypothyroidism?
A
- *levothyroxine (L-T4)
- can be dosed in terms of weekly dose; miss one, take 2 th enext day (pro-hormone)
can use L-T3 (cytomel) but short acting and requires multiple daily dosing
in primary hypothyroidism: monitor TSH levels (4-6 weeks after dose change)
in central hypothyroidism - monitor free T4 levels
23
Q
how do you treat hyperthyroidism?
A
meds: beta blockade: propanol, metoprolol, etc
iodine (to block T3, T4 production)
thionamides (PTU or methimazole)
steroids (if thyroiditis is suspected)
radioactive iodine
surgery
24
Q
Wolff-Chaikoff vs. Jod-Basedow effect
A
WC: “wolff choke off” –> sudden iodine load temporarily (few weeks) inhibits organification of iodinde, thus blocking synthesis, iodine is useful for acute treatment of severe hyperthyroidism (but be aware of jod-basedow)
JB: “jod blastoff effect” –> iodine induced thyrotoxicosis, may be delayed, caused by administration of iodine in setting of autonomous thyroid tissue and prior iodine deficiency; be careful giving iodine to patient with Graves’ who just arrived from a third world country
25
anti-thyroid drugs
thionamides :
propylthiouracil or PTU: now falling out of favor, but "safer" in pregnancy (3 times a day dosing)
methimazole: (tapazole) drug of choice
both rarely cause allergic reactions (neutropenia or even agranulocytosis)
26
what is the therapy of choice for graves' or hot nodules?
radioactive iodine
- takes 1-4 months to work
- can cause transient exacerbation of hyperthyroidism, but usually mild
- 85-90% of graves patients become permanently hypothyroid by 6-12 months
- may worsen pre-existing
- ophthalmopathy in graves' patients, especially smokers
hot nodule patients - great treatment
27
who is a candidate for thyroid surgery?
mechanical complicaitons of goiter, or urgency for treatment (wants to get pregnant, doesn't want to deal with radiation or thionamide risks)
28
maternal demand for thyroid hormone (increases or decreases) during pregnancy?
INCREASES - up to 50% by 2nd trimester: in patients requiring oral T4 replacement, must often increase the dose
29
does mild thyroid functional disease require treatment?
may not have to treat all cases since typically patients are asymptomatic, but even subclincial thyroid disease may have subtle physiologic sequelae
30
subclinical thyrotoxicosis
low TSH, but T3 and T4 normal
31
subclinical hypothyroidism
High TSH, but T3 and T4 normal
32
what is the most common reason to treat subclinical thyrotoxicosis/hyperthyroidism?
risk of afib (3x increase)
33
are thyroid nodules common?
yes! typically asymtomatic, often difficult to palpate; under-reporting of true incidence
woman more than men
cancer is uncommon but not rare. should get an US to better visualize nodules
34
```
cold (non-functioning) nodules; the vast majority of nodules
hot nodules (autonomous/TSH independent T4/T3 production) are almost never malignant
```
benign adenomatous nodule
35
how common is thyroid cancer?
5-15%
36
whats the first thing to do if you find a nodule?
check TSH! (should be done before biopsy)
37
are overactive nodules usually cancerous?
no! (so if TSH is low (hyperthyroidism), do a I-123 scan/uptake
38
when is a FNA required for a nodule?
if > 1.5 cm
39
most nodules are what kind?
hypofunctioning or "cold"
40
Management of Suspicious Nodules (suspicious FNA cytology result) or Big Goiters with Compressive Symptoms
surgery!
41
is thyroid cancer common?
yes, but usually non-fatal
| women to men 3:1
42
who are microcarcinomas (thyroid) most common in?
elderly (
43
most common type of thyroid cancer?
papillary and follicular - well differentiated = still behave in some respects like normal thyroid tissue
44
which thyroid cancer is almost uniformly fatal?
anaplastic (occurs in older people, very rapid)
45
thyroid cancer where loses thyroid character, no longer takes up iodine
poorly differentiated - much worse prognosis
46
what is medullary thyroid cancer?
very uncommon (
47
treatment of thyroid cancer
surgical removal of all normal thyroid tissue and cancer (if possible)
follicular cell-derived tumors (papillary follicular): radioactive iodine 131 to destroy any of above that is left
medullary thyroid cancer: surgery only
48
surveillance for follicular-derived cancers
monitoring with US and serum thyroglobulin (TG - a high TG suggests cancer is present), radioactive iodine whole scans
49
surveillance for medullary thyroid cancer
calcitonin
| CT scans
50
complex, multifactorial condition of increased fat stores with both genetic, behavioral and environmental causes
obesity
51
T or F; higher body weights are associated with an increase in all-cause mortality
T
52
metabolic syndrome criteria
at least 3 of the following 5:
waist cicrumference:
men > or equal to 102 cm/40 inches
women > or equal to 88 cm/ 35 inches
triglycerides greater or equal to 150
HDL men or equal to 130/85 or antihypertensive meds
fasting glucose greater than 100
53
body shapes with increased risk
apple (android)
ovoid (fruit box
pear shaped/gynoid has no increased risk
54
these are endocrine organs for the language of fat-inflammation and pro-coagulation
adipose cells
55
what is leptin?
pro-satiety hormone - signals to the brain how much fat the body has so it adjusts to eat less and keeps the fat stores in equilibirum
56
what is gherlin?
hormone that counteracts leptin, hunger signaling
57
what is adiponectin?
an "anti-inflammatory" hormone that makes the body more sensitive to insulin. this is decreased in obesity
58
which fat is "good fat"
brown fat - found in babies, more metabolically active. generates non-shivering heat
59
how many cormorbid conditions with obesity?
62
60
when should you consider anti-obesity medication?
BMI> 30 or >27 with a comorbid condition, have utilized lifestyle approaches of diet, physical activity and behavioral tools to the best of their ability, unable to control weight or reach target weight loss with a lifestyle treatment alone. has reasonable expectations and understanding of how meds work, no contraindications
61
absolute contraindication for obesity meds?
childbearing age
62
qualifiers for surgical treatment for obesity?
BMI> or equal to 40, and BMI of 35 or higher who have 2 other cardiovascular risk factors
The LAP-BAND System-patients with a BMI of ≥ 30 kg/m2 and one or more obesity related comorbid conditions.
63
deficiencies common in gastric bypass
vitamin B12 and K
64
what is the functional unit of the thyroid?
follicle (balls of cells)
65
what is the active ingredient in the thyroid hormone?
iodine
66
what is hypothyroxinemia?
low plasma levels of thyroid hormone, which leads to low saturation of nuclear thyroid hormone receptors
67
constellation of signs and symptoms caused most commonly by deficiency of thyroid hormone
hypothyroidism
68
when is the fetal thyroid gland operational by?
10-12th week- fetal thyroid economy includes a contribution from maternal thyroid hormones (T3, T4)
69
what is cretinism?
maternal iodine deficiency - hypothyroidism in utero. leads to impaired brain development, short stature, deaf mutism, spasticity, thyroid gland structural abnormalities (goiter)
70
what happens with congenital hypothyroidism?
can be compensated in utero (mostly) but must be treated after birth. MAJOR PREVENTABLE CAUSE OF MENTAL RETARDATION
71
clinical manifestations of hypothyroidism in newborns/infants
```
birth weight >4 kg
gestation >42 weeks
jaundice
hypothermia
cyanosis
macroglossia
large posterior fontanelle
umbilical hernia
retardation of bone maturation
respiratory difficulties/distress
poor feeding/sucking ability
failure to gain weight
hoarse cry
decreased activity/lethargy
```
72
biggest sign of hypothyroidism in children and adolescents
growth retardation
73
clinical manifestations of hypothyroidism in adults
```
fatigue, lethargy
depression
increased sensitivity to cold
mild weight gain (wont make you obese)
dry skin, brittle nails and hair
delayed ankle reflex (relaxation phase delayed)
hypercholesterolemia
hyponatremia
```
74
biggest complication with hypothyroidism?
myxedema coma (severe hypothyroidism plus other medical condition)
decreased mental status, bradycardia, etc
usually people with another medical problem like pneumonia, or elderly patients who can't communicate well
75
what happens with hyperthyroidism in utero?
```
spontaneous abortion
premature labor
low birth weight
stillbirth
preeclampsia (CHF)
```
76
Hyperthyroidism in Childhood
Accelerated growth but early epiphyseal maturation (advanced bone age)
Delayed puberty
Tendency towards lower weight
Almost always Graves’ disease
77
symptoms of hyperthyroidism
```
heat intolerance/sweaty
palpitations
increased perspiration
sleep disturbance
tremor
irritability
fatigue
anxious
```
Hyperactivity
Hyperreflexia
tachycardia/atrial arrhythmia (increased risk of afib)
78
worst complication of hyperthyroidism
thyroid storm (usually patients have comorbidity like cardiac problems)
temperature, CNS changes, GI dysfunction, tachycardia, CHF
79
autoimmunce thyroid disease of hypothyroidism
hashimotos
80
autoimmunce thyroid disease of hyperthyroidism
graves disease
81
most common etiology of hypothyroidism in adults
acquired
- autoimmune: ***hashimoto's disease (90%)(and post-thyroiditis) --> chronic lyphocytic thyroiditis (common, painless, lymphocytic ilfiltrate, perhaps most common AI disease)
- drug related (amiodarone, INF-alpha)
- post surgical (thyroid cancer patients)
82
less common etiologies of hypothyroidism in adults
congenital (rare)
central (uncommon) - TSH deficiency, or less commonly TRH deficiency (pituitary/hypothalamic tumors)
central = pituitary proglem
83
what can thyroiditis cause
a spectrum, from hashimotos to graves (can be associated with hypo , hyper, or euthyroidism)
usually painless
common in first post-partum year!
Attempts to subtype = many unhelpful names
Painless = Hashimoto’s = Chronic
Painful = Subacute = Granulomatous = DeQuervain’s
Infectious (rare)
Reidel’s = sclerosing (destructive)
84
how long does thyroiditis last?
NO LONGER THAN 6 MONTHS - if you have hyperthyroidism lasting longer than 6 months, not thyroiditis
thyroid hormone leaking into the blood, causes hyperthyroidism
very common in year after pregnancy
3 phase: hyperthyroidism, hypothyroid briefly, then should recover (self limiting)
85
most common etiology of thyrotoxicosis?
graves disease, esp in younger patients
Single or multiple autonomously functioning “hot” nodule(s): more likely in older patients (toxic uni/multi-nodular goiter)
86
what is graves disease?
A distinct autoimmune syndrome
TSH-receptor stimulating antibodies,cell-mediated as well..
Much more common in women
Thyrotoxicosis (goitrous), Opthalmopathy (widened, palpebral fissure, periorbital edema, proptosis, chemosis, conjuctival injection), pretibial myxedema (rash)
"stare" - can be associated with any kind of hyperthyroidism
"orbitopathy/opthalmopath" specific to graves disease
TSH receptors in the thyroid, so if you have an antibody that mistakenly turns on that receptor, its like you have TSH, so it makes more thyroid hormone
87
what should you always include with you are giving report about a thyroid patient?
include the eye, or else you're not thinking
88
what is nodular thyrotoxicosis?
"hot nodule" = abnormal growth of follicular cell into a lump that produces thyroid hormone autonomously (regardless of TSH)
Can be one nodule, or many, i.e. toxic multinodular goiter
More prevalent in older patients than younger
89
Simplified Ddx of Low TSH:
Thyrotoxicosis
Central Hypothyroidism
Pregnancy (hCG effect)
Non-thyroidal illness/low T3 syndrome (pressors, steroids, etc.)
90
Simplified Ddx of High TSH
```
Hypothyroxinemia
Central Hyperthyroidism (rare)
```
91
which is more adrenal weight, the cortex or medulla?
cortex (90%), and has 3 different zones
92
what is made in the zona glomerulosa?
aldosterone ('salt')
93
what is made in the zona fasiculata?
cortisol ('sugar')
94
what is made in the zonal reticularis?
androgens ('sex')
95
what is made in the medulla?
catecholamines
96
what are adrenal hormones derived from?
common cholesterol
97
what are androgens precursors for?
dihydrotestosterone and estradiol
98
what can too much ACTH production do?
excess alpha MSH which can cause hyperpigmentation
99
what is excess cortisol's effect on bones?
suppresses osteoblast production and stimulates bones to be thinner
100
organs effected by cortisol
brain, bone, CVS, immune system, kidney, skin/connective tissue
101
which can be converted to sex steroids? DHEA or DHEAS?
DHEA
102
adrenal androgens
androstenedione, DHEA, DHEA sulfate - direct biologic activity minimal, act as precursors for peripheral conversion --> testosterone and dihydrotestosterone
103
what are female androgens important for?
axillary hair and pubic hair development
104
Adrenal Androgen Excess in prepubertal boys
isosexual precocious puberty - early puberty
105
Adrenal Androgen Excess in adult women
cystic acne, hirsutism, male type baldness, menstrual irregularities, oligoovulation or anovulation, infertility and or frank virilization
106
Adrenal Androgen Excess in pubertal girls
heterosexual precocious puberty
107
what are the catecholamines?
epinephrine, norepinephrine, dopamine
108
what is synthesized and stored in the adrenal medulla?
epi and NE (+ peripheral sympathetic nerves)
(dopamine - precursor for NE - is found in the adrenal medulla and peripheral sympathetic nerves
109
how does catecholamine action come about?
stressful stimuli causes catecholamine production, which causes a "fight or flight" response (in creased HR, BP, myocardial contractility, and cardiac conduction velocity)
110
difference between cushing's syndrome and cushing's disease
disease is pituitary cause only, syndrome is all causes
111
signs and symptoms of cushing's
weight gain, menstrual irregularity, hirsuitism, psychiatric dysfunction, back ache, obesity, plethora, moon face, HTN, bruising, purple striae
112
when are your ACT/cortisol levels highest and lowest?
highest in the morning at 8:00 and lowest at midnight
113
ACTH independent cushing's syndrome causes
Adrenal adenoma (10-15%) and carcinoma (
114
ACTH-dependent cushing's syndrome
```
Cushing's disease (pituitary-dependent) - 70%
Ectopic ACTH syndrome - 15%
Ectopic CRH syndrome
Macronodular adrenal hyperplasia
Iatrogenic (treatment with ACTH 1-24)
```
115
Pseudo-cushing’s syndrome
alchoholism, depression, obesity
116
how do you diagnose cushings?
mightnight plasma or sailvary cortisol
24 hr urinary free cortisol
low-dose dexamethasone suppression test (1 mg x 1 at 11pm OR 0.5 mg q6hr x 48 hrs) (normal result
117
if ACTH (>15) and cortisol are high, where is the source of the hypercortisolism?
pituitary (tumor maybe)
if ACTH is
118
most common sources of ectopic ACTH
small cell lung carcinoma, pancreatic tumors, lung carcinoids
119
treatment of cushings
surgical: pituitary resection, adrenalectomy, resection of ectopic ACTH source
medical: mitotane (for ACC), ketoconazole, metyropone, aminoglutethimide, trilostane
120
signs/symptoms of adrenal insufficiency
Dehydration, hypotension, or shock out of proportion to severity of current illness
Nausea and vomiting with a history of weight lost and anorexia
Abdominal pain
Unexplained hypoglycemia
Unexplained fever
Hyperpigmentation or vitiligo
Other autoimmune endocrine deficiencies, such as hypothyroidism or gonadal failure
Fatigue, weakness
Hyponatremia, hyperkalemia, azotemia, hypercalcemia, or eosinophilia
121
causes of primary adrenal insufficiency (Addison's disease)
Autoimmune: Sporadic or Autoimmune polyendocrine syndrome
Infections: Tuberculosis, Fungal, Cytomegalovirus, HIV
Metastatic tumor
Infiltrations: Amyloid, Hemochromatosis
Intra-adrenal hemorrhage: (Waterhouse-Friderichsen syndrome) after meningococcal septicemia, anticoagulation
Adrenoleukodystrophies
Congenital adrenal hypoplasia: DAX-1 mutations, SF-1 mutations
ACTH resistance syndromes
Bilateral adrenalectomy
Medications: ketoconazole, metyrapone
Need to have 90% infiltration to get adrenal insufficiency, so even if you loose the function of one gland, still won’t really see effects
122
Causes of Secondary Adrenal Insufficiency
```
Exogenous glucocorticoid therapy
Pituitary surgery or irradiation
Pituitary apoplexy
Postpartum pituitary infarction (Sheehan’s syndrome)
Granulomatous disease (TB, sarcoid)
Isolated ACTH deficiency
Lymphocytic hypophysitis
Idiopathic
Metastatic disease to pituitary
```
123
problems with long-term glucocorticoid therapy
Abrupt cessation --> suppress HPA axis --> adrenal insufficiency (can occur with synthetic progestogen, medroxyprogesterone acetate, megestrol acetate, have GC agonist activity)
Excessive longterm use --> Cushing’s syndrome
Duration
124
eval & treatment of adrenal insufficiency
```
Evaluation:
8am cortisol 10 : rules out AI
8am cortisol 3-10 : 250 mcg ACTH stim test --> >18 at 30 min or 60 min rules out AI
ACTH high : primary AI
ACTH low/low normal : secondary AI
```
125
adrenal insufficiency treatment
IVF
glucocorticoud replacement: hydrocortisone 15-30 mg divided BID - TID
mineralocorticoid in primary AI = florinef 0.1 mg/day
126
10% of all HTN patients present with what?
primary hyperaldosteronism
127
when should you suspect primary hyperaldosteronism?
when HTN is resistant to treatment ( on 3 drugs including diuretic)
hypokalemia
adrenal incidentaloma
128
what is the most common cause of hyperaldosteronism?
aldosterone producing adenoma (APA)
-65%, more severe, increase in aldo secretion, tx-surgery
bilateral hyperplasia is less common and is idiopathic hyperaldo = IHA. - 30-40%, milder, less aldo secretion, tx is drugs
129
diagnosis of hyperaldosteronism
PAC/PRA ( aldosterone/renin ratio) > 20 or 30 and PAC > 15
confirm with salt loading (2 1 g sodium chloride tablets TID x 3 days)- On day #3, collect a 24-hour urine for aldosterone, sodium, and creatinine
24-hour urine sodium should exceed 200 meq to confirm adequate sodium loading
Urine aldosterone excretion >12 mcg/24 hours confirms hyperaldosteronism
- excess salt should normally suppress aldosterone secretion
- abdominal CT to look for adrenal mass - if unilateral mass, then adrenalectomy**if patient is > 40 yo then must do bilateral adrenal vein sampling to distinguish unilateral source
130
what is congenital adrenal hyperplasia (CAH)
caused by various genetic defects in the enzymes involved in cortisol biosynthesis
decrease in cortisol production --> increase ACTH
manifestations due to decreased production of cortisol and decrease or increased production of mineralcorticoids and androgens (depending on the site of enzyme defect)
131
which deficiency is the most common with congenital adrenal hyperplasia?
21-hydroxylase deficiency (95% of CAH)
132
what are catecholamine-secreting tumors that arise form chromaffin cells of the adrenal medulla?
pheochromocytomas
Paragangliomas or extra-adrenal pheochromocytomas – arise from sympathetic ganglia
133
symptoms of patients with pheo
HTN (may or may not have)
sweating
palpitations
paroxysmal HA (abrupt, bilateral, diminishes in hour)
134
when should you screen for pheo?
```
When patients are having Hyperadrenergic spells (eg, self-limited episodes of nonexertional palpitations, diaphoresis, headache, tremor, or pallor)
Adrenal incidentaloma
Idiopathic dilated CM (cardiomyopathy)
Resistant HTN
Onset of HTN at a young age (eg,
```
135
familial pheo forms
younger, usually bilateral, many with no HTN
136
what should you order in the management of pheo?
fractionated metanephrines
fractionated catecholamines
(urine/plasma)
137
with adrenal diseases, what should you order first- biochemical testing or imaging?
biochemical testing
138
which organs play a major role in assuring calcium homeostasis?
the skeleton, the gut and the kidney
139
what accounts for 90% of cases of hypercalcemia?
PHPT (primary hyperparathyroidism) and malignancy
140
epidemiology of PHPT
incidence is 1 in 500-1 in 1000
women> men
postmenopausal women- first decade
141
etiology of PHPT
sporadic benign solitary adenoma - 80-85%
| parathyroid hyperplasia 10-15%
142
What symptoms do most patients with PHPT present with?
none!
Incidentally discovered on routine biochemical screening test
143
Osteitis Fibrosa Cystica
characterized by subperiostal resorption of the distal phalanges, tapering of the distal clavicles, a “salt and pepper” appearance of the skull, bone cysts, and brown tumors of the long bones. It is now seen in fewer that 5% of pts with PHPT.
144
what is th emost common overt complication of PHPT?
kidney stones (about 10-15% now)
145
which meds can cause increase calcium levels?
litium and thiazide (HCTZ)
146
what is the only curative therapy for PHPT?
parathyroidectomy
bone density improves, incidence of fractures and kidney stones reduces
147
Possible complications of PTx
Damage to the recurrent laryngeal nerve – hoarseness and reduced voice volume
Permanent hypoparathyroidism
Transient hypocalcemia
148
Guidelines for Monitoring Patients with Asymptomatic PHPT Who Do Not Undergo Parathyroid Surgery
serum calcium - annually
skeletal - every 1-2 years (3 sites)
renal: eGFR annual, serum creatinine annually. If renal stones suspected, 24-h biochemical stone profile, renal imaging by x-ray, US, or CT
149
should patients with asymptomatic PHPT limit calcium intake?
no (low Ca diet could lead to further PTH stimulation), should have vitamin D repletion though + adequate hydration and encourage ambulation
Cinacalcet
150
FHH - Familial Hypocalciuric Hypercalcemia
autosomal dominant (2% of cases of PHPT)
Inactivating mutation of the CASR gene – impaired calcium suppression of PTH secretion
Patients usually have mild or no symptoms
Benign course, rarely need treatment
151
what is the cause of 90% of hypercalcemia of hospitalized patients?
malignancy - negative prognostic factor
HHM (humoral hypercalcemia of malignancy): Most common mechanism hypercalcemia in cancer.
152
Pharmacologic Therapy for Hypercalcemia Associated with Cancer
fluids!!! and phosphonates
153
how should you treat Bisphosphonate-Refractory Hypercalcemia of Malignancy
denosumab
154
most common cause of hypocalcemia/vitamin D deficiency?
postsurgical (on thyroid gland)
155
hypoparathyroidism
low Ca, High Phos, low/nl PTH
gland destruction (postop), autoimmune, congenital (DiGeorge syndrome: dyspmorphic features, anomalies)
impaired parathyroid function (hypomagnesemia)
resistance to PTH (hypomagnesemia)
156
Pseudohypoparathyroidism
genetic disorder of target-organ unresponsiveness to PTH (low Ca, low phos, but high PTH)
Type 1a is the most common form: Albright hereditary osteodystrophy – short stature, round face, short neck, obesity, brachydactily, subcutaneous ossifications, mental retardation.
157
Causes of Vitamin D deficiency
```
Inadequate exposure to sunlight
Winter
Pollution
Sunscreen
Increased skin pigmentation
```
Obesity
Malabsorption syndrome – fat soluble vit
Meds: anti-convulsants, glucocorticoids, medications HIV/AIDS
Granulomatous diseases, lymphomas, PHPT – increase metabolism of vitamin D
158
signs/symptoms of hypocalcemia
```
Tetany, Chvostek’s (Tap facial nerve 2 cm ant to earlobe – contraction facial muscles), Trousseau’s (Elicited by inflating blood pressure cuff to about 20 mmHg above SBP for 3 min – carpal spasm)
Muscle twitching/cramping
Circumoral/acral tingling
Abdominal cramps
Generalized weakness, fatigue, depression
Laryngospasm, bronchospasm, seizures
Basal ganglia calcifications on imaging
Long QT, Heart failure
```
159
Diagnosis/Management of hypocalcemia
Io Ca2+, Mg, Phos, iPTH, 25(OH)D
Goals of treatment
Alleviate symptoms (Ca 8.5-9.0 mg/dl)
Heal demineralized bones
Maintain acceptable Ca and avoid hypercalciuria (>300/24h)
```
Calcium – IV, PO
Vitamin D
Thiazides
Mg replacement
Replacement Therapy with PTH
```
160
what is osteoporosis?
compromised bone strength (bone density, bone quality)
161
Risk Factors for Osteoporosis
Low peak bone mass
Anorexia, bulimia, athletic amenorrhea
Decline estrogen – menopause
Endocrine: hypogonadism, hyperthyroidism, primary hyperparathyroidism, acromegaly
Nutrition/lifestyle: vitamin D deficiency, malabsorption syndromes
Medications: Glucocorticoids, thyroid hormone excess, Pioglitazone, Anti-seizure meds
Other: Primary hypercalciuria
162
adult bone mass is achieved until what age?
30
163
symptoms of osteoporosis
none! until you have a fracture
164
diagnosis of osteoporosis
DEXA scan
T-scores between —1.0 and —2.5 define osteopenia. T-scores less than or equal to —2.5 define osteoporosis
A T-score is the number of standard deviations an individual’s bone density result is from the mean of healthy, gender-matched young adult controls
165
what is a fragility fracture?
fall from a standing height or less
166
Osteoporosis Evaluation and Management
Address secondary causes, if any
Ensure adequate calcium and vitamin D intake
1000-1200 mg of elemental calcium daily are recommended
At least 800-1200 international units of vitamin D daily are recommended. However, it is best to measure 25(OH) vitamin D to ensure intake is adequate.
Encourage weight-bearing exercises
Address fall prevention
Avoid tobacco, limit alcohol intake
Pharmacologic therapy if indicated
167
what is the most used pharmacologic treatment for osteoporosis?
bisphosphonates
then SERMS, estrogen (but increases risk for heart disease), denosumab, PTH
168
what does teriparatide do?
physiologically moves calcium from bone
when given intermittently and @ low doses --> anabolic effect on blasts
169
type 1 diabetes
Beta-cell destruction- complete lack of insulin
170
type 2 diabetes
Beta- cell dysfunction and insulin resistance
171
which DM is inheritable?
type 2 (type I is not, its autoimmune)
172
what percent of all cases of diabetes are type 1?
5%
173
two forms of DM I
immune mediated- beta cells destroyed by autoimmune process
- genetic predisposition, autoimmune reaction may be triggered by viral infection, toxins. Destroys beta cells in pancreas that produce insulin
idiopathic - cause of beta cell function loss is unknown
circulating autoantibodies (ICA, GAD65)
174
what are the long-term complications of DM?
microvascular --> retinopathy, nephropathy (microalbuminuria, gross albuminuria) and end-stage renal disease (ESRD), neuropathy (peripheral or autonomic) --> can lead to amputation
macrovascular complications--> coronary heart disease cerebrovascular disease, peripheral vascular disease
175
what is diagnostic for DM?
HgA1C > or equal to 6.5% (normal is 4-6)
fasting glucose >/= 126
random >/= 200
176
what disease can lead to insulin resistance and they can develop DM later in life?
PCOD
177
what is microalbuminuria an indicator of?
incipient nephropathy, especially in type 1 diabetics (over 80% of patients with persistent microalbuminuria develop nephropathy)
In type 2 diabetes, microalbuminuria is also an indicator of macrovascular disease, especially coronary artery disease
178
how can you reverse microalbuminuria?
ACE inhibitor. if you dont reverse, and it progresses to gross albuminura, diabetic kidney disease is past the point of no return and they will need dialysis
179
what is the first sign of diabetic kidney failure?
proteinuria
180
microvascular and macrovascular complications are predicted by what in DM?
microvascular - duration of diabetes, A1C, BP
macrovascular complicatons: duration of diabetes, A1C, BP, lipids
