UWORLD endocrine Flashcards
(61 cards)
1
Q
Clinical presentation of Hypopituitarism
A
- ACTH deficiency (secondary adrenal insufficiency): postural hypotension, tachycardia, fatigue, weight loss. hypoglycemia, eosinophila
- Hypothyroidism (central): fatigue, cold intolerance, constipation, dry skin, bradycardia, slowed DTRs
- Gonadotropins: Women –> Amenorrhea, infertility. Men –> Infertility, loss of libido
2
Q
Describe the lab values seen in Panhypopituitarism
A
- Central adrenal insufficiency: Low cortisol and ACTH
- Hypogonadotropic hypogonadism: low FSH, LH, testosterone
- Central hypothyroidism: low or inappropriately normal TSH, Low free T4
3
Q
Is aldosterone affected in hypopituitarism?
A
NO, it is regulated primarily by the RAS
4
Q
Describe the lab/imaging of a prolactinoma
A
- Serum prolactin often >200 (normal is <15)
- Rule out renal insufficiency (creatinine) and hypothyroidism (TSH, thyroxine)
- MRI of brain/pituitary
5
Q
Treatment of a prolactinoma
A
- Dopamine agonist (cabergoline)
- Trans-Sphenoidal surgery
6
Q
What are the LH and TSH levels like in a prolactinoma
A
- LH: low or inappropriately normal
- TSH may be also low or normal
7
Q
Describe the clinical features of Painless thyroiditis (silent thyroiditis)
A
- Variant of chronic autoimmune thyroiditis
- Mild, brief hyperthyroid state
- small, NONtender goiter
- Spontaneous reccover
8
Q
Diagnostic testing of Painless thyroiditis (Silent thyroiditis)
A
- Positive TPO antibody
- Low radioiodine uptake
9
Q
radioiodine uptake in Graves disease
A
High
10
Q
Describe Stuma ovarii
A
a very rare cause of thyrotoxicosis and is due to production of thyroid hormone by an ovarian teratoma
- it typically present in women over age 40 with a pelvic mass, ascites, or abdominal pain
- Thyroid gland NOT enlarged
11
Q
What is the effect of intensive glycemic control in type 2 diabetes on MACROvascular complications (Acute mi, stroke)?
A
No change
12
Q
What is the effect of intensive glycemic control in type 2 diabetes on MICROvascular complications (nephropathy, retinopathy)?
A
decrease
13
Q
What is the effect of intensive glycemic control in type 2 diabetes on all cause mortality?
A
-No decrease possibly because the microvascular benefits are offset by complications of hypoglycemia.
14
Q
What is the pathophysiology of Milk-alkali syndrome
A
- Excessive intake of calcium and absorbable alkali
- Renal vasocontriction and decreased GFR
- Renal loss of sodium and water, reabsorption of bicarb
15
Q
Symptoms of Milk-Alkali syndrome
A
- Nausea, vomiting, constipation
- Polyuria, polydipsia
- Neuropsychiatric symptoms
16
Q
lab finding in milk-alkali syndrome
A
- Hypercalcemia
- Metabolic alkalosis
- Acute kidney injury
- suppressed PTH
- hypophosphatemia
- hypomagnesemia
17
Q
Treatment of Milk-Alkali syndrome
A
- Discontinuation of causative agent
- Isotonic saline followed by furosemide
18
Q
Milk alkali syndrome in pt with osteoporosis is likely due to ingestion of what
A
calcium carbonate
19
Q
What medications raise the risk of milk alkali syndrome
A
- Thiazide diuretics
- ACEI’s/ARBs
- NSAIDs
20
Q
How does thyrotoxicosis effect heart rhythm
A
- Sinus tachy
- Premature atrial and ventricular complexes
- Afib/flutter
21
Q
How does thyrotoxicosis effect hemodynamics
A
- Systolic HTN and increased pulse pressure
- increase contractility and cardiac output
- decrease systemic vascular resistance
- increase myocardial oxygen demand
22
Q
describe the mechanism behind HTN in HYPOthyroidism
A
increased systemic vascular resistance
23
Q
Systolic HTN in thyrotoxicosis is caused by what
A
hyperdynamic circulation resulting from increased myocardial contractility and heart rate
24
Q
Describe the cutaneous finding in a glucagonoma
A
-Necrolytic migratory erythema: Erythematous papules/plaques on face, perineum, extremities . . .Lesions enlarge and coalesce over next 7-14 days with central clearing and blistering, crusting and scaling at borders
25
GI symptoms in Glucagonoma
- diarrhea
- anorexia
- abdominal pain
- occasional constipation
26
random associations with glucagonoma
- weight loss
- Neuropsychiatric (ataxia, dementia, proximal muscle weakness)
- Venous thrombosis
27
Diagnosis of glucagonoma
- Hyperglycemia with elevated glucagon >500
- Normocytic normochromic anemia due to likely anemia of chronic disease or glucagon directly affecting erythropoiesis
- Abdominal imaging (CT or MRI) to localize tumor and/or metastases
28
Hypocalcemia in an alcoholic patient with hypomagnesemia and hypophosphatemia. explain pathophysiology?
- Hypomagnesemia is very common in hospitalized alcoholics and can cause hypocalcemia by inducing resistance to PTH as well as by decreasing PTH secretion.
- The cause of hypomagnesemia in alcoholics is multifactorial, and may include urinary losses, malnurtrition, acute pancreatitis and diarrhea
29
Hypercalcemia can occur in prolonged immobilization due to what?
- increased osteoclastic activity, especially in individuals with high baseline rate of bone turnover
- Bisphosphonates can reduce this hypercalcemia and prevent bone loss
30
Fever and sore throat in any patient taking antithyroid drugs suggests what?
Agranulocytosis
- drugs should be stopped and WBC count checked
- Routine WBC count measurement in patients taking antithyroid drugs is not cost effective
31
A patient has an elevated total T4 concentration but her TSH is normal, suggesting a euthyroid state (increased TBG, increased total T4, normal free T4). What things can cause this?
- Estrogens (pregnancy, OCPs, HRT)
- Hepatic dysfunction
- Meds (tamoxifen)
32
if euthyroid and decreased TBG (Decreased Total T4, normal free T4) what can cause this?
- Hormonal abnormalities (Cushing, glucocorticoids)
- Hypoproteinemia (e.g. nephrotic syndrome, starvation)
- Meds (e.g. niacin, high dose androgens)
33
In a patient with symptoms of Hyperthyroidism but a low RAIU, this suggests either release of preformed thyroid hormone (ie, thyroiditis) or exogenous thyroid hormone uptake. Explain how to differentiate?
- Serum thyroglobulin levels can make the distinction
- Elevated=endogenous
- decreased=exogenous or factitious thyrotoxicosis
34
Symmetric distal sensorimotor polyneuropathy is the most common neuropathy in patients with diabetes, and clinical features depend on the type of nerve fiber involved. Describe the difference between small and large fiber involvement
- Small: predominance of positive symptoms (Pain, paresthesias, allodynia)
- Large: negative symptoms (numbness, loss of proprioception and vibration sense, diminished ankle reflexes)
35
Clinical presentation of a VIPoma
- Watery diarrha
- Hypo or achlorhydria due to a decrease in gastric acid secretion
- Associated flushing, lethargy, nausea, vomiting, muscle weakness/cramps
36
Lab findings in VIPoma
- HYPOkalemia (increase intestinal potassium secretion)
- Hypercalcemia (bone resorption)
- Hyperglycemia
- secretory diarrhea with increase sodium and osmolol gap <50
37
Diagnosis of VIPoma
- Watery diarrhea with VIP level > 75
| - Abdominal CT or MRI to localize tumor in pancreas (usually in pancreatic tail)
38
Describe the treatment of patients with macroprolactinomas (>10mm) or symptomatic tumors
- should be treated with dopaminergic agonists (cabergoline, bromocriptine) which can normalize prolactin levels and reduce tumor size
- patients who fail to respond or who have very large tumors (>3cm) should be referred for transsphenoidal resection
39
Describe the use of radiotherapy in treating prolactinoma
- patients with residual prolactinoma tissue following resection can be consiered for radiotherapy
- However, the response is generally delayed and it may lead to panhypopituitarism
40
What are the causes of osteomalacia
- Malabsorption
- intestinal bypass surgery
- celiac sprue
- Chronic liver disease
- Chronic Kidney disease
41
Symptoms/signs of osteomalacia
- May be asymptomatic
- bone pain and muscle weakness
- muscle cramps
- difficulty walking, waddling gait
42
Diagnosis of osteomalacia
- Increased Alk phos and PTH
- Decreased serum calcium and phosphorus, and urinary calcium and 25 OH-D
- X rays may show thinning of cortex with reduced bone density
- Bilateral and symmetric pseudofractures (looser zones) are characteristic radiologic finding
43
what is the pathophysiology of osteomalacia
-defective mineralization of the organic bone matrix
44
What are the causes of ACUTE hypocalcemia
- Neck surgery (parathyroidectomy)
- Pancreatitis
- Sepsis
- Tumor lysis syndrome
- Acute alkalosis
- Chelation: Blood (citrate) transfustion, EDTA, foscarnet
45
This type of adrenal insufficiency has only glucocorticoid and adrenal androgen deficiency with preservation of mineralocorticoid production (regulated primarily by the RAS, not pituitary)
Central or secondary
46
What heart pathology does acromegaly cause
Concentric myocardial hypertrophy leading to diastolic dysfunction, along with left ventricular dilation and global hypokinesis
47
what is the leading cause of death in patients with acromegaly
-cardiovascular disease but normalization of growth hormone levels following successful treatment markedly reduces cardiovascular mortility
48
The cardiomyopathy of acromegaly is often worsened by what other conditions
- concurrent HTN
- Obstructive sleep apnea
- valvular heart disease
49
plasma aldosterone to plasma renin activity ratio of > what number suggests primary hyperaldosteronism
20
50
Hypothyroidism can cause additional metabolic abnormalities such as what
- Hyperlipidemia
- Hyponatremia
- Asymptomatic elevation in creatinine kinase (usually <10x normal)
- serum transaminases
51
The best markers indicating resolution of ketonemia in DKA are what?
- serum anion gap
| - direct assay of beta-hydroxybutyrate, which is the predominant ketone in DKA
52
HTN in pheochromocytoma can be intermittent or sustained. The paroxysms of severe HTN can be precipitated by what?
- increases in intra-abdominal press (e.g. tumor palpation, positional changes)
- Surgical procedures
- A number of meds, particularly anesthetic agents
53
Describe the treatment of patients with diabetic gastroparesis
- combination of optimizing diabetes control; dietary modification with increased fiber intake and small, frequent meals; and medications to improve gastric emptying
- Metoclopramide has both prokinetic and antiemetic properties and is useful for symptomatic relief of nausea, bloating, and postprandial fullness in patients with diabetic gastroparesis
54
clinical features of neurofibromatosis type 1
- cafe au lait spots
- neurofibromas
- axillary freckling
- intracranial tumors
- skeletal anomalies
55
The patient has myalgias and proximal muscle weakness with an elevated serum creatine kinase level. In a relatively young, otherwise healthy woman with fatigue and delayed DTRs, this presentation is most consistent with what?
hypothyroid myopathy
56
how do you differentiate polymyositis from hypothyroid myopathy
- polymyositis is characterized by symmetric proximal muscle weakness.
- ESR and CK are elevated in approximately half of patient
- myalgias are typically absent or mild and DTRs are normal ****
57
effect of oral estrogen on thyroxine requirement
-increases TBG concentration so it increases thyroixine requirement
58
How does acid base shifts effect calcium concentration
-increased pH (alkalosis) causes hydrogen ions to dissociate from albumin molecules, thereby freeing up the albumin to bind with calcium . . . hypocalcemia
59
What hormone is used to diagnose acromegaly
- GH stimulates hepatic IGF-1 secretion, which is responsible for most of the clinical manifestations of acromegaly
- IGF-1 levels in acromegaly are consistently elevated throughout the day
- In contrast, GH levels can fluctuate widely and cannot be used alone to diagnose acromegaly
60
Patients with suspected acromegaly need to undergo confirmatory testing with an oral glucose suppression test. Describe this
- In normal individuals, administration of glucose rapidly suppresses GH secretion
- In acromegaly, GH will not be suppressed and may paradoxically increase
61
what does chronic kidney disease do to calcium levels
decreases renal production of vitamin D, leading to HYPOcalcemia, hyperphosphatemia, and increase PTH
