Endocrinology (Clinical Review Q's) Flashcards
What would hyponatremia with an absence of edema indicate?
SIADH
low plasma sodium w no edema
What might darkening skin/ hyperpigmentation indicate?
High levels of ACTH
How can one shut down hormone production rapidly in hyperthyroid patients?
Clinically: very high iodide doses are used to rapidly shut down thyroid hormone production in hyperthyroid patients
If you see a rise in hormones that are secreted by the pituitary what could this mean?
lung cell carcinoma- secretes hormones that would normally be secreted by pituitary and causes all sorts of endocrine problems
or pituitary tumor?
Match disease to symptom…
postpartum hemorrhage/shock; results in massive pituitary cell death.
Trauma/Stress (endocrine pathology)
Sheehan’s Syndrome – postpartum hemorrhage/shock; results in massive pituitary cell death
What is Kallman Syndrome?
Rare genetic disease (1:8000 men/1:40,000 women)
GnRH neurons fail to enter CNS
Characterized by reproductive failure and anosmia
Heritable: X-linked = Kal1, autosomal = Kal2
What could a patient being treated with Lithium for bipolar disease experience? How/why?
DIABETES INSIPIDUS
Decreased renal responsiveness to AVP
Acquired: lithium treatment
also can have decreased renal responsiveness- most common reason in adults is acquired (lithium treatment prescribed for bipolar disease, enters through epithelial sodium channels but cant get out so accumulates inside cell and interferes w AVP abiity to traffic AQP2 channels) accumulation inside cell may either decrease AQP2 synthesis or increase lysosomal degradation of these channels
(Lithium can also inhibit NIS symporter in follicular epithelial cell)
What will AVP levels be in a case of acquired diabetes insipidus?
Describe differential diagnosis.
-AVP levels typically normal bc thirst mech. can compenstate for changes in plasma osmolality
(differential diagnosis- alter plasma osmolality and see what happens through water restriction)
What is the effect of treating someone with carbenoxolone?
What does carbimazole do?
Certain drugs (carbenoxolone) will inhibit 11B-HSD2 resulting in excess MR activation.
Carbenoxolone used to treat esophogeal inflammation – increases local cortisol
Carbimazole – inhibits thyroid peroxidase (TPO) -treatment for thyroid storm!
What might happen if someone eats too much licorice? (real licorice/glycyrrhetinic acid)
Licorice (glycyrrhetinic acid) also inhibits 11B-HSD2 – excessive consumption can lead to increased sodium and water retention.
Why might you target 11B-HSD1 for drug therapy for DM T2?
Local production of Cortisol by 11B-HSD1 potential pathogenic role in DM T2 – novel drug target
target enzyme bc idea is local prod. of cortisol esp in abdomen can contribute to obesity and type II Diabetes. so potential drug target
What will a 21alpha hydroxylase deficiency lead to? Why?
What are some clinical indications?
Congenital Adrenal Hyperplasia (CAH)
21 alpha hydroxylase deficiency - results in excess DHEA, no mineralocorticoids or glucocorticoids
Most common cause of CAH
Clinical indications: virilization (masculinization) ambiguous genitalia at birth, sodium loss
No cortisol
No aldosterone/MR activity
Increased androgens
Clinical presentation: Hypotension Hyperkalemia High plasma renin Masculinization High ACTH
What are pheochromocytes?
What are pheochromocytomas?
chromaffin cells of adrenal medulla
Pheochromocytomas – tumors originating from chromaffin cells.
Pheochromocytomas: the 10% tumor
What can vanillylmandelic acid levels be used to indicate clinically?
can be used to clinically detect tumors prod. excess EPI or NE.
What could hypertension (no response to medication), headaches, and tachycardia indicate?
Diagnosis? What tests?
Treatment?
Pheochromocytomas – tumors originating from chromaffin cells.
Diagnosis: measurements of urinary metanephrines
Treatment: surgery, pre-surgery: alpha/beta blockers.
What could opthalmopathy- edema behind eyes, and tachycardia indicate?
Graves disease -
Autoimmune – antibodies (Long-acting thyroid stimulator - LATS)
stimulate TSH receptor
- Elevated T4/T3
- Diffuse symmetrical goiters with hyperthyroid symptoms: tachycardia,
opthalmopathy, irritability, hyperactivity, heat intolerance, weight loss,
nervousness, muscle wasting
Histology of thyroid gland from patient with Graves Disease. Note:
scant colloid, tall columnar activated follicular cells, and infiltration of
lymphocytes.
tachycardia- effects of thyroid hormone on heart med. those catecholamine effects
get opthalmopathy- edema behind eyes (defects in carbohydrate metabolism..buildup of polysaccharides in interstitial space which retains water… so these individual easy to spot bc looks like eyes bulging out of heads)
Diffuse goiter with hypothyroid symptoms: lethargy, fatigue, hair loss, cold intolerance, brittle nails decreased appetite, weight gain.
Hashimotos Thyroiditis
Autoimmune destruction of thyroid follicles
Antibodies against TPO, TG
Symptoms:
High fever Tachycardia Altered mental status Severe nausea, vomiting, diarrhea Severe circulatory collapse
What is diagnosis? How to treat?
CLINICAL DISORDERS – THYROID STORM
Emergency life threatening situation
Hyperthyroid coupled with severe acute illness
-normal hyperthyroid response … coupled w that massive up regulation of stress response, catecholamines v high…
can result in severe circulatory collapse bc all vessels dilate and body tries to perfuse all tissues at once, we don’t have enough blood to perfuse all tissues at once and circulatory system will eventually collapse
Treatment:
Propylthiouracil (PTU – only acute treatment)
Carbimazole (methimazole)
Beta blockers to restore normal heart function
PTU-treatment …will block thyroid peroxidase (TPO)…stop making thyroid hormone (some liver toxicity issues so not given long term)
carbimazole- given to inhibit TPO in hyperthyroid patients and give beta blockers.
What is Kussmaul breathing?
What might this indicate in a patient? What type of diabetes?
Would labs show high or low PCO2?
deep rapid breathing
respiratory compenstaion in response to decreased bicarb and increased CO2
Low PCO2
Why is the blood pressure low and the pulse rate high (T1DM)?
Dehydration – vomiting, osmotic diuresis results in low BP
Decreased baroreceptor firing (less stretch due to low blood flow) induces tachycardia.
What is Sheehan’s Syndrome?
Sheehan’s Syndrome – postpartum hemorrhage/shock; results in massive pituitary cell death
Usually affects other pituitary cell types – loss of axillary and pubic hair
(progesterone will increase blood volume in preg. to anticipate possible hemorrhage… )
What type of therapy for Crohn’s disease?
Glucocorticoid therapy
Describe Euthyroid sick syndrome.
Hypothyroid symptoms with low T4/T3
Normal TSH and thyroid
What is Laron Syndrome?
GH Deficiency
Dwarfism (children): related to GH
Laron Syndrome –
genetic defect in GH receptor – no production of IGF-I. Treatment with IGF-I can prevent dwarfism
Plasma GH levels are normal to high (lack of feedback).
What is African Pygmy?
African Pygmy
Partial defect in GH receptor – some IGF-I response.
Plasma levels of GH normal – no pubertal increase in IGF-I.
