Endocrine Disorders Flashcards
1
Q
T/F When carcinomas cannot be histologicially distinguished from adenomas, the only sure sign of malignancy is metastasis.
A
1
True; We see this, for example, with the parathyroid glands.
1
Q
____________________________ syndrome refers to the unregulated secretion of hormones and hormone-like compounds from tumors
A
- Paraneoplastic
2
Q
T/F The posterior pituitary hormones are prolactin and ACTH.
A
- False; ACTH and prloactin are anterior pituitary hormones. The posterior pituitary hormones are ADH and oxytocin.
3
Q
T/F Neurohormones released by the posterior pituitary are not synthesized in the posterior pituitary.
A
- True; They are synthesized by neurons whose cell bodies lie in the hypothalamus.
4
Q
T/F Neurohormones released by the anterior pituitary are not synthesized in the anterior pituitary.
A
- False; Anterior pituitary hormones are synthesized by ant. pituicytes (ant. pituitary cells) -under the regulation of hypothalamic releasing hormones.
5
Q
T/F Continual stimulation of the adrenal medulla by ACTH would lead to hyperplasia of the adrenal medulla
A
- False; The adrenal medullary cells do not express ACTH receptors on their surfaces. They are thus oblivious to ACTH and would not respond to it at all.
6
Q
T/F Continual stimulation of the adrenal cortex by ACTH would lead to adrenocortical hyperplasia
A
- True; ACTH does indeed stimulate the adrenal cortex- esp. the zona fasiculata that makes cortisol; Continual ACTH stimulation of the cortex would indeed lead to adrenocortical hyperplasia. There is a similar relationship between the follicular cells of the thyroid and TSH.
7
Q
The [anterior/ posterior] pituitary is also known as the adenohypophysis.
A
- anterior; The anterior pituitary is a gland (‘adeno-‘) derived from the oral mucosa.
8
Q
The [anterior / posterior] pituitary is also known as the neurohypophysis.
A
- posterior; The posterior pituitary is derived from the neural tissue (‘neuro-‘) of the hypothalamus.
9
Q
The [anterior/ posterior] pituitary is derived from epithelial cells in the mouth region which migrate upward in the head.
A
- anterior
10
Q
The connection between the hypothalamus and the [anterior/ posterior] pituitary gland is mainly a vascular one.
A
- anterior
11
Q
The connection between the hypothalamus and the [anterior/ posterior] pituitary gland is mainly a neural one.
A
- posterior
12
Q
The ________________________ is the stalk of the pituitary gland.
A
- infundibulum
13
Q
___________________ is a control loop whereby the product or output of a system acts back on the system to repress or stop its own production.
A
14
Negative feedback, or feedback inhibition
14
Q
The _________________________, a region of the brain, largely controls the secretion of hormones by the anterior pituitary.
A
- hypothalamus
15
Q
A(n) ___________________ hormone regulates the hormonal functioning of a distant endocrine gland.
A
- tropic
16
Q
____________ is the hypothalamic hormones that controls the release of TSH by the anterior pituitary.
A
- TRH, or Thyrotropin Releasing Hormone
17
Q
_________________ is the hypothalamic hormones that controls the release of FSH and LH by the anterior pituitary.
A
- GnRH, or Gonadotropin Releasing Hormone
18
Q
______________ is the hypothalamic hormones that controls the release of ACTH by the anterior pituitary.
A
- CRH, or Corticotropin Releasing Hormone
19
Q
T/F Laron dwarfism is easily treated in children by administration of growth hormone.
A
- False; Recall that Laron hormone is due to insensitivity of the growth hormone receptor. Therefore, supplying exogenous growth hormone will do little to overcome that deficiency. But growth hormone is tropic in that it elecits the release of
somatomedin (mostly from liver cells), and it is somatomedin that actually stimulates growth in stature. Thus administration of somatomedin, not growth hormone, will bypass the receptor deficiencies of Laron dwarfism and cause growth of long bones.
20
Q
________________________ refers to the deficient secretion of one or more of the hormones secreted by the pituitary.
A
- Hypopituitarism
21
Q
______________________ refers to total failure of pituitary function; no pituitary hormones are being secreted.
A
- Panhypopituitarism
22
Q
____________________, or ischemic necrosis of the pituitary, usually is caused by hypotension secondary to postpartum hemorrhage.
A
- Sheehan syndrome
23
Q
In children, ___________________ results from the inadequate secretion of growth hormone.
A
- pituitary dwarfism
24
____________________ refers to a condition marked by short statue due to extreme insensitivity of the growth hormone receptor to growth hormone.
26. Laron dwarfism
25
Which ONE of the following is not a classic symptom of panhypopituitarism?
```
A. General weakness
B. Heat intolerance
C. Poor appetite
D. Weight loss
E. Hypotension
F. Amenorrhea and impotence
G. In men, loss of muscle mass, and facial and pubic hair
H. Pallor
I. (None. All of the above are typical symptoms of panhypopituitarism)
```
B. Panhypopituitarism produces cold intolerance. The loss of TSH also causes low serum T3 and T4. Since these control the metabolic rate, in their absence, a person does not produce much body heat and feels chilled all the time. In other words, they cannot tolerate chilly temperatures because they are not producing enough internal heat. Note that the lack of T3 and T4 also account for the general weakness, poor appetite, weight loss, and hypotension (remember that T3 and T4 increase sympathetic influence, so in their absence...).
26
T/F Pituitary adenomas are about three times more common in women than in men.
28. False; Pituitary adenomas are actually most common in middle-aged men.
27
T/F Although the pituitary gland is composed of several populations of pituicytes, each secreting their own set or sets of hormones, a functional pituitary adenoma usually only secretes one hormone.
29. True; for example, a prolactinoma arises from the lactotropic pituicytes and only secretes prolactin.
28
T/F In pre-pubertal patients, somatotropic adenomas result in pituitary dwarfism.
30. False; A somatotropic adenoma would secrete high levels of growth hormone and thus cause gigantism, not dwarfism.
29
T/F In post-pubertal patients, somatotropic adenomas result in acromegaly.
31. True; Remember that with high levels of growth hormone, the growth extends to the soft organs as well, such that cardiomegaly is common.
30
[Lactotropic/ Somatotropic / Thyrotropic / Corticotropic] adenomas secrete prolactin.
32. Lactotropic, otherwise known as a prolactinoma.
31
[Lactotropic/ Somatotropic / Thyrotropic / Corticotropic] adenomas secrete ACTH.
33. Corticotropic
32
Cushing [disease/ syndrome ] refers to hypercortisolism produced by a corticotropic adenoma of the pituitary.
34. Cushing disease. The name is specifically reserved to the hypercortisolism due to a prolactinoma; all other types of hypercortisolism are refered to as Cushing syndrome.
33
_____________________ are benign neoplasms of the anterior lobe of the pituitary and are often associated with excess secretion of pituitary hormones and evidence of corresponding
endocrine hyperfunction.
35. Pituitary adenomas
34
A _____________________ is a common name for a lactotropic adenoma.
36. prolactinoma
35
________________, a dopamine analog, can suppress the secretion of prolactin from a prolactinoma.
37. Bromocriptine; Recall that PIF- prolactin inhibitory factor- is dopamine, and bromocriptine is a dopamine analog (agonist).
36
Which ONE of the following is not a typical mass effect produced by pituitary adenomas?
```
A. Bitemporal hemianopsia
B. Oculomotor palsy
C. Bell palsy
D. Severe headache
E. Hypothalamic dysfunction
F. (None. All of the above are typical symptoms resulting from the mass effects of a pituitary adenoma)
```
38. C. Bell palsy, which is probably caused by viral inflammation of the facial nerve.
37
Which ONE of the following is not a typical symptom of a prolactinoma?
```
A. Amenorrhea
B. Dysfunctional uterine bleeding
C. Galactorrhea
D. Infertility
E. Impotence
F. (None. All of the above are typical symptoms of a prolactinoma)
```
39. B. These symptoms of a prolactinoma are easily explained. Galactorrhea results in a woman from the high prolactin levels. Recall that prolactin inhibits the release of LH and FSH by inhibiting the hypothalamic release of GnRH. This results in infertility, amenorrhea, and impotence. DUB is due to high unopposed estrogen levels, a situation we would not see with low FSH and LH.
38
T/F The treatment for diabetes insipidus may include ADH replacement therapy.
40. True; Of course this would be of most benefit to patients with central diabetes insipidus.
39
A key feature of SIADH is sodium retention and the inability to concentrate the urine.
41. False; It's backwards- the situation described is for diabetes insipidus. In SIADH a patient hypersecretes ADH, so the condition is characterized by the inability to dilute the urine, and sodium loss (natriuresis) resulting in hyponatremia. Also, be careful on the exam- I might flip this question, so it DOES describe SIADH.
40
T/F A common cause of SIADH is a paraneoplastic small cell carcinoma of the lungs.
42. True
41
T/F The clinical picture of SIADH is dominated by hyponatremia, cerebral edema, and CNS dysfunctions such as headache and vomiting; severe cases may lead to convulsions and coma.
43. True
42
In [central/ nephrogenic] diabetes insipidus, the posterior pituitary secretes insufficient ADH.
44. Central
43
In [central/ nephrogenic] diabetes insipidus, the kidney tubules show insufficient response to circulating ADH.
45. nephrogenic
44
______________________ is a posterior pituitary disorder characterized by the inability to concentrate the urine, with resulting polyuria and polydipsea; the biochemical basis is an insufficient ADH activity.
46. Diabetes insipidus
45
_________________ is a disorder characterized by excessive release ADH from the posterior pituitary gland or another source.
47. SIADH, or syndrome of inappropriate ADH secretion
46
Which ONE of the following is not a common treatment option for SIADH?
A. Long-term fluid restriction
B. IV saline
C. Demeclocycline or tolvaptan
D. (None of the above, i.e., they are all common treatments for SIADH)
49. D. Of course, treating any underlying illness would also be part of the treatment plan.
47
Which ONE of the following is NOT a typical symptom/finding of diabetes insipidus?
```
A. Intense thirst
B. Copious urine output
C. Renal calculi
D. Lack of sugar in the urine
E. (None. All of the above are typical symptoms of diabetes insipidus)
```
50. No renal calculi.
48
[Iodine / Calcium/ Vitamin D/ Iron / Sulfur / Zinc ] is a chemical element found in the thyroid hormones T3 and T4.
51. Iodine
49
The ____________________________ cells of the thyroid gland are responsible for the production of the thyroid hormones T3 and T4.
52. follicular; parafollicular cells produce calcitonin.
50
____________________ from the anterior pituitary stimulates follicular activity in the thyroid and the release of T3 and T4 hormones.
53. TSH; And TSH in turn is regulated by TRH from the hypothalamus.
51
Which ONE of the following statements is NOT TRUE regarding the thyroid hormones T3 & T4?
A. T3 & T4 are catecholamines
B. T3 & T4 are derived from two molecules of tyrosine
C. T3 & T4 contain three or four iodine molecules
D. T3 & T4 are stored in colloid attached to thyroglobulin
E. T3 has about 10 times more biological activity than T4
F. T4 is converted to T3 in the peripheral tissues (mainly liver) of the body
G. (None. All of the above are true regarding T3 and T4)
54. A. Like T3 and T4, catecholamines are also formed from the amino acid tyrosine. However, T3 and T4 are not catecholamines- they do not possess the catechol group.
52
Which ONE of the following conditions is most likely to lead to a goiter?
A. Secondary hypothyroidism due to failure of the hypothalamus or pituitary gland.
B. Primary hyperthyroidism due to a small but hypersecreting thyroid tumor
C. Secondary hyperthyroidism due to a small but hypersecreting pituitary tumor
55. C. In case A, the hypothalamus/pituitary is misbehaving, so that TSH levels will be low. In B, high levels of thyroid hormones will suppress TSH production, so again, TSH levels will be low. In any case, remember my rule-goiters are likely to develop when TSH or TSH-like stimulation is excessive.
53
T/F Goiters can develop in a setting of hypopituitarism secondary to hypothalamic or anterior pituitary failure.
56A
False
With hypothalamic or anterior pituitary failure, TSH levels will be low. Hence, no goiter.
54
T/F Thyroid cancer can lead to the production of a goiter.
56B
True
A tumor can enlarge the thyroid and thus cause a goiter.
55
T/F Goiters will not develop in the absence of TSH overstimulation.
56C
False
While TSH overstimulation is a major cause of goiters, there are other ways they can develop in the absence of elevated TSH levels. Neoplasia and TSI antibodies immediately come to mind.
56
T/F Lack of dietary iodine may lead hypothyroidism but does not lead to goiter formation.
56D
False
Lack of dietary iodine is a MAJOR cause of goiters worldwide.
57
T/F Goiters can develop in a setting of hypopituitarism via primary failure of the thyroid itself.
56E
True
Thyroid failure means low T3 and T4 levels, which in turn means high TSH levels and thyroidal overstimulation. Hence, primary thyroid failure can indeed lead to goiter formation.
58
T/F Goiters can develop in the setting of hyperthyroidism via a functional pituitary adenoma.
56F
True
If the tumor is a thyrotropic adenoma (which secretes TSH) then yes, a goiter may develop.
59
T/F Goiters can develop in the setting of hyperthyroidism via antibody stimulation of the thyroidal follicular cells.
56G
True
This is precisely the case in Graves disease.
60
T/F Patients with nontoxic goiter are usually euthyroid.
57
| True
61
T/F For reasons that are unclear, in nontoxic goiter the capacity of the thyroid to produce thyroid hormones is impaired.
58
| True
62
_______________________ refers to an enlargement of the thyroid that is not
associated with functional, inflammatory, or neoplastic alterations
59
Nontoxic goiter; 'Nontoxic' means that patients are neither hypothyroid nor hyperthyroid- they are euthyroid. These goiters are not associated with functional disturbances (such as pituitary hypo- or hyper-secretion, there is no evidence of thyroiditis (inflammation), and there is not sign of a thyroid tumor.
63
T/F Typically, in cases of nontoxic goiter, the ability of the thyroid gland to produce thyroid hormones is impaired, and patients thus develop hypothyroidism.
60A
False
With nontoxic goiters, the ability of the thyroid gland to produce hormone is impaired, but the body compensates (increased thyroid stimulation via TSH) so that a patient usually maintains normal T3 and T4 levels.
64
T/F Diffuse nontoxic goiters are the early stage of the disease and are most common during pregnancy and in adolescent patients.
60B
| True
65
T/F Diffuse nontoxic goiters often show nodularity.
60C
False
If they showed nodularity, they would be multinodular nontoxic goiters.
66
T/F Endemic nontoxic goiters occur in a defined region of the world- usually an area that is iodine deficient or an area where people consume large quentities of crops that inhibit thyroid hormone synthesis (e.g., crucifers).
60D
True
Of course, lack of dietary iodine is the MAJOR cause of endemic goiters worldwide.
67
T/F In diffuse nontoxic goiters, the entire thyroid is enlarged, its follicles hyperplastic and hypertrophic.
60E
True
Thyroid failure means low T3 and T4 levels, which in turn means high TSH levels and thyroidal overstimulation. Hence, primary thyroid failure can indeed lead to goiter formation.
68
T/F (Diffuse nontoxic) Sporadic goiters are idiopathic.
60F
True
Also, sporadic goiters are more common in women than men, for unknown reasons.
69
T/F Multinodular nontoxic goiters represent the early stage of the disease and are more common in adolescent patients.
60G
| False
70
T/F Multinodular nontoxic goiters can evolve into hyperthyroidism.
60H
True
These are called toxic multinodular goiters; their hyperthyroidism differs from Graves disease in that toxic multinodular goiters do not produce the infiltrative ophthalmopathy (exophthalmos).
71
T/F Some multinodular goiters progress to cancer.
60I
True
The frequency of this progression is low (~5%) but not zero.
72
T/F Nontoxic goiters may cause dysphagia, dyspnea, jugular compression, hoarseness.
60J
| True
73
T/F Exophthalmia is seen in all types of hyperthyroidism.
61
False; It is pathognomonic for Graves disease, and is not seen in other types of hyperthyroidism such as toxic multinodular goiter.
74
T/F Goiters do not develop in untreated Graves disease.
62
| False; In fact, goiters are quite common in untreated Graves disease.
75
T/F Ironically, the hyperthyroidism of untreated Graves disease may evolve into thyroid failure and hypothyroidism.
63
True; Presumably the constant stimulation and hyperthyroidism overwhelms the gland; it fails and the person lapses into hypothyroidism.
76
T/F In Graves disease, high T3/T4 levels are accompanied by low TSH levels.
64
| True; And important diagnostic results.
77
T/F In Graves disease, radioactive iodine uptake tests show decreased uptake of iodine by the thyroid gland.
65
| False; In graves disease, the thyroid is overactive- it's going to take up lots of iodine!
78
T/F A typical course of treatment for Graves disease is (1) administer adrenergic antagonists to alleviate the heightened sympathetic effects, followed by (2) administration of antithyroidal drugs to inhibit T3/T4 release.
66
| True
79
_________________ is a hypermetabolic state caused by elevated circulating levels of free T3 and T4; hyperthyroidism is the most common cause of this condition.
67
| Thyrotoxicosis
80
__________________ is caused by excessive thyroid activity.
68
| Hyperthyroidism
81
_____________ is an autoimmune disorder caused by antibodies that agonistically bind to the surface TSH receptors of the thyroid follicular cells, stimulating them.
69
| Graves disease, the most common cause of hyperthyroidism
82
Circulating antibodies called _______________, or TSIs, are the root cause of Graves disease.
70
| thyroid stimulation immunoglobins
83
____________ is a common antithyroid drug commonly used to treat the hyperthyroidism of Graves disease.
71
| Either propylthiouracil or methimazole work here.
84
Which ONE of the following is NOT a typical symptom of the hyperthyroidism of Graves disease?
A. Tachycardia and cardiac palpitations
B. Diarrhea
C. Pallor and cold, clammy skin
D. Exophthalmos
E. Weight loss and increased appetite
F. Restlessness, nervousness, anxiety, and sweating
G. (None. All of the above are typical symptoms of hyperthyroidism)
71
| C. Cold, clammy, pallid skin is typical of hypothyroidism.
85
T/F In thyrotoxic patients, the skin tends to be cool, dry, and pallid due to decreased peripheral blood flow and vasoconstriction.
72A
False
This is backwards. Remember that high circulating levels of T3/T4 activates the sympathetic nervous system. Sympathetic effect on the skin is vasodilation (to increase heat loss), resulting in warm, soft, moist, and flushed skin.
86
T/F In thyrotoxic patients, cold intolerance is common.
72B
False
Again, backwards. These patients are producing lots of internal heat, so they have heat intolerance (and would probably welcome cool air around them).
87
T/F In thyrotoxic patients, tachycardia and palpitations are common.
72C
True
Think sympathetic effects on the body- fast heart beat and palpitations are examples.
88
T/F In thyrotoxic patients, cardiomegaly and cardiac arrhythmias may develop, and these may lead to congestive heart failure and death.
72D
True
Another cardiac complication is thyrotoxic cardiomyopathy.
89
T/F Thyrotoxic effects on the nervous system include nervousness, insomnia, and inability to concentrate
72E
True
Again, think sympathetic effects on the body
90
T/F Constipation is common in thyrotoxic patients
72F
False
Usually the opposite is seen- increased peristalsis resulting in diarrhea.
91
T/F In thyrotoxic patients, distal muscle weakness but increased muscle mass are common.
72G
False
Again, backwards. In thyrotoxicosis we see proximal muscle weakness and decreased muscle mass.
92
T/F High T3/T4 levels activates osteoclasts, leading to osteoporosis and hypercalcemia.
72H
True
One effect of the osteoporosis is increased rate of bone fracture.
93
T/F Untreated infantile hypothyroidism results in permanent mental retardation known as cretinism.
73
| True
94
T/F Depending on cause, myxedema can usually be reversed with iodine supplements or thyroid hormone replacement therapy.
74
| True
95
T/F The mental retardation of cretinism will usually disappear once the underlying hypothyroidism is successfully treated.
75
| False; The underlying hypothyroidism may disappear on treatment, but any mental impairments will be permanent.
96
T/F In primary hypothyroidism, circulating T3 and T4 levels are low but serum TSH levels are high.
76
| True
97
T/F In secondary hypothyroidism, circulating T3 and T4 levels are low but serum TSH levels are high.
77
False; The fact that this is secondary hypothyroidism means that the pituitary (or hypothalamus) has the problem, and TSH levels are consequently low.
98
[Primary/ Secondary] hypothyroidism occurs as a result of hypothalamic or pituitary disease.
78
Secondary; Remember, if the problem is in the gland itself, it's primary. If the problem affects the gland but is not in the gland itself, it is secondary.
99
[Congenital/ Acquired / Autoimmune ] hypothyroidism is also known as cretinism.
79
| Congenital
100
One cause of [congenital/ acquired / autoimmune ] hypothyroidism is total thyroidectomy.
80
Acquired; This should be a give-away. Thyroidectomy is a post-partum procedure- children aren't born with it, so it is not a congenital condition, and antibodies and immune cells are not involved so it is not an autoimmune condition. This happens to you during your life, i.e., it is acquired.
101
______________________ arises from a functional failure of the thyroid and its inability to meet the body's demands for T3 and T4.
81
| Primary hypothyroidism
102
__________________ is the most common cause of autoimmune hypothyroidism.
82
| Hashimoto thyroiditis
103
In ________________, proteoglycans accumulate in the extracellular matrix and bind water; the skin appears dull, puffy, and yellowed, with sparse hair and periorbital puffiness.
83
| myxedema
104
Which ONE of the following is NOT a typical symptom of hypothyroidism?
```
A. Sleepiness
B. Reduced stamina and endurance
C. Lack of mental alertness
D. Decreased motility in the intestine (=constipation)
E. Bradycardia
F. Weak, stiff, achy skeletal muscles
G. Brittle hair
H. (None. All of the above are typical symptoms of hypothyroidism)
```
84
| H.
105
T/F Hypothyroidism: The skin is cool, pale, and puffy.
85A
True
This peculiar form of edema is termed myxedema.
106
T/F Hypothyroidism: The skin is quite moist due to increased sweating.
85B
False
Decreased sympathetic activity decreases sweat and sebaceous gland activities, so the skin is not moist but dry.
107
T/F Hypothyroidism: Skin lesions heal slowly.
85C
True
This is due to decreased peripheral circulation (poor blood flow to the skin).
108
T/F Hypothyroidism: Hoarseness is common.
85D
True
Due to increased deposition of glycosaminoglycans in and around the larynx.
109
T/F Hypothyroidism: Heart rate and stroke volume are increased.
85E
False
Backwards; the decreased sympathetic activity lowers heart rate and stroke volume, so that cardiac output is reduced. Exercise intolerance is common
110
T/F Hypothyroidism: Lethargy and somnolence may develop, and slowed mentation causes memory loss.
85F
True
This is due, at least in part, to thelowered cardiac output- the brain is hypoxic.
111
T/F Hypothyroidism: Reproductive effects of hypothyroidism include anovulation, menstrual irregularities, erectile dysfunction, and oligospermia.
85G
True
Loss of libido is another effect.
112
T/F Hypothyroidism: Diarrhea
85H
False
Hypothyroidism slows the GI tract, so decreased motility results in constipation and stool impaction.
113
T/F Hypothyroidism: In children, untreated hypothyroidism may cause dwarfism.
85I
True
The so-called 'thyroid dwarfism.' This is due to the fact that thyroid hormones are required for growth hormone to fully manifest.
114
T/F Hypothyroidism: Brittle hair
85J
| True
115
T/F Mild cases of Hashimoto thyroiditis often require no treatment, and moderate cases are often treated with thyroid hormone replacement therapy.
86
| True; Surgery is only required when there are compression effects on surrounding tissues
116
T/F Hashimoto thyroiditis and Graves disease are the two most common immunologically mediated disorders of the thyroid.
87
| True
117
T/F Hashimoto thyroiditis results in gradual thyroid failure due to autoimmune destruction of the thyroid gland.
88
| True
118
T/F Microscopic examination of a thyroid with Hashimoto thyroiditis reveals extensive infiltration of the parenchyma by lymphocytes and plasma cells; germinal centers are common.
89
| True
119
T/F In Hashimoto thyroiditis, the thyroid follicles are enlarged and hypertrophic due to the elevated TSH levels.
90
False; In Hashimoto thyroiditis, the follicles are being destroyed by the immune system, and thus are atrophic (not enlarged). The gland itself may be enlarged, not by follicular hypertrophy, but by the accompanying inflammation and fibrosis.
120
T/F The most common initial presentation of Hashimoto thyroiditis is a painless goiter in a middle-aged woman.
91
| True; Usually there are signs of hypothyroidism as well.
121
T/F Unlike Graves disease, goiters are not seen in Hashimoto thyroiditis.
92
False; Goiters can develop in Hashimoto thyroiditis through a combination of TSH stimulation, immune cell infiltration and inflammation, and fibrosis.
122
___________________ is a term that encompasses a heterogeneous group of inflammatory disorders of the thyroid gland, including those that are caused by autoimmune mechanisms or by infectious agents.
93
| Thyroiditis; Note the phrase 'inflammatory disorders of the thyroid', cuing you onto the fact that this a thyroidisis.
123
___________ is characterized by the presence of circulating antibodies to thyroid antigens and features of cell-mediated immunity to thyroid tissue.
94. Hashimoto thyroiditis
124
___________________ refers to a situation sometimes seen in Hashimoto thyroiditis where the longer-term hypothyroidism is preceded by a transient thyrotoxicosis due to massive disruption of thyroid follicles.
95
| Hashitoxicosis
125
T/F Most (at least 90%) patients with subacute thyroiditis return to normal thyroid function without medical treatment.
96
| True
126
T/F Subacute thyroiditis is best treated with thyroid hormone replacement therapy.
97
| False; In most cases, patients with subacute thyroiditis require no specific medical treatment.
127
__________________ thyroiditis is a self-limited thyroid condition associated with a triphasic clinical course of hyperthyroidism, hypothyroidism, and return to euthyroidism.
98
Subacute thyroiditis; This definition applies to all the variants of this disorder- de Quervain, painfull, and postpartum subacute thyroiditis.
128
Which ONE of the following best describes the typical clinical course of subacute thyroiditis?
A. Hyperthyroidism, followed by hypothyroidism, and then a return to euthyroidism
B. Hyperthyroidism, followed by euthyroidism, and then persistent hypothyroidism
C. Hypothyroidism, followed by hyperthyroidism, and then a return to euthyroidism
D. Hypothyroidism, followed by euthyroidism, and then persistent hyperthyroidism
E. (None of the above describe the typical clinical course of subacute thyroiditis)
99
A. We've seen this pattern before. Initial destruction of thyroidal follicles releases massive amounts of preformed T3 and T4, and hyperthyroidism ensues. When the hormone stores are exhausted, hypothyroidism appears. Eventually, the
thyroid recovers, and euthyroidism returns.
129
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
This thyroiditis is a self-limited thyroid condition associated with a triphasic clinical course of hyperthyroidism, hypothyroidism, and return to euthyroidism.
100A
| General
130
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
This thyroiditis is an infrequent, self-limited disorder of the thyroid characterized by granulomatous inflammation and caused by viral infection.
100B
| de Quervian thyroiditis
131
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
The initial presenting symptom of this thyroiditis is typically an exquisitely tender (i.e., painful) thyroid gland.
100C
| de Quervian thyroiditis
132
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
This thyroiditis is characterized by lymphocytic infiltration and mild enlargement of the thyroid but without thyroid pain.
100D
| Painless thyroiditis
133
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
This thyroiditis is the most common cause of thyroid pain.
100E
| de Quervian thyroiditis
134
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
This thyroiditis is a rare disorder of unknown etiology characterized by extensive fibrosis involving the
thyroid and contiguous neck structures.
100F
| Riedel thyroiditis
135
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
This thyroiditis usually requires no medical treatment at all
100G
| de Quervian thyroiditis
136
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
Although most patients with this thyroiditis become euthyroid within a year, about a third of patients will progress to frank hypothyroidism within a 10 year period
100H
| painless thyroiditis
137
T/F Subacute thyroiditis:
General, de Quervian thyroiditis, painless thyroiditis, or Riedel thyroiditis?
This thyroiditis involves heavy fibrosis in the neck region and is treated with some combination of corticosteroids, tamoxifen, and/or surgery
100I
| Riedel thyroiditis
138
T/F On gross examination, follicular adenoma presents as numerous nodules that project from the surface of the thyroid.
101. False; This description is precisely that of a multinodular goiter. Follicular adenomas present as a solitary nodule that projects from the surface of the thyroid. In fact, this is how you tell the two apart- single nodule, follicular adenoma; multiple nodules, multinodular goiter.
139
T/F Most thyroid cancers are medullary carcinomas of the parafollicular cells.
102
| False; The most common type of thyroid cancer is papillary carcinoma; this is a follicular cancer.
140
T/F Papillary carcinomas typically invade the lymphatics and spread to the nearby cervical lymph nodes.
103
True; Papillary carcinomas do not usually spread to more distant sites because they do not invade the blood vessels for hematogenous spread.
141
T/F Medullary carcinomas typically invade the blood vessles; they often spread to the lungs, bones, and liver.
104
| True
142
T/F Medullary and follicular carcinomas account for the majority of thyroid cancers associated with previous exposure to ionizing radiation (e.g., radioactivity)..
105
False; This 'honor' goes to papillary carcinomas. There was an increase in papillary carcinomas after Chernobyl, and will undoubtedly be another increase in Japan after the Fukushima incident.
143
T/F In papillary thyroid carcinoma, the presence of metastases to the cervical lymph nodes at the time of surgery does not change the prognosis.
106
| True
144
T/F Papillary thyroid carcinoma has a poor prognosis; less than 20% of patients survive 5 years post diagnosis.
107
| False; PTC has an excellent prognosis, with a 10 year survival rate of over 95%.
145
__________________ refers to a benign neoplasm of the thyroid that exhibits follicular differentiation.
108
| Follicular adenoma
146
___________________ is the most common tumor of the thyroid gland.
109
| Follicular adenoma
147
Which ONE of the following does NOT pertain to papillary thyroid carcinoma?
A. A painless palpable nodule in an otherwise normal gland.
B. A nodule with enlarged cervical lymph nodes.
C. Cervical lymphadenopathy in the absence of a palpable thyroid nodule.
D. Tumors larger than 0.5 cm can be detected as cold areas in a thyroid scintiscan.
E. (None, i.e., all of the above pertain to papillary thyroid carcinoma)
110
| E. They're all true of papillary thyroid carcinoma.
148
T/F The parathyroid glands release parathyroid hormone (PTH), the most important hormone in lowering serum calcium levels.
111
| False; PTH raises serum calcium levels.
149
Most individuals have [1/ 2 / 3 / 4 / 6 / 8 / 10] parathyroid glands, located on the posterior aspect of the thyroid gland.
112
Four is the typical number, though someindividuals are known to have up to 8 parathyroid glands located anywhere in the neck or upper chest.
150
Which ONE of the following is not a recognized mode of action of parathyroid hormone (PTH) in raising serum calcium levels?
A. PTH causes bone cells to absorb the bony matrix & release calcium into blood
B. PTH causes the kidneys to reabsorb more Ca++, thus reclaiming calcium from the urine and returning it to the plasma.
C. Via vitamin D, PTH increases absorption of Ca++ by the intestinal mucosa
D. PTH causes the tissues of the body to take up less calcium from the plasma, thereby helping to keep plasma levels high.
E. PTH stimulates the conversion of relatively inactive vitamin D to its more active form, calcitriol.
F. (None. All of the above are recognized modes of action of PTH.)
113
| D. PTH is not known to affect calcium uptake by body tissues..
151
T/F Patients with all forms of hypoparathyroidism are successfully treated with vitamin D and calcium supplementation.
114
| True
152
T/F The hallmark of hypoparathyroidism is tetany, due to the accompanying hypocalcemia.
115
| True
153
T/F Pseudohypoparathyroidism presents with hypocalcemia, such that tetany and cramping are common.
116. True; Recall that a lowered blood calcium level decreases the threshold of neurons and muscle cells, so that they are excited and depolarize (i.e., fire a nerve signal) more easily. This translates into highly excitable- irritable- nerves and spastic muscles.
154
[Surgery / Autoimmune phenomena / Parathyroid agenesis / Genetic mutations] is/are themost common cause of hypoparathyroidism.
117
| Surgery- they took out the parathyroids!
155
[Hypercalcemia/ Hypocalcemia] is the consistent result of hypoparathyroidism.
118
| Hypocalcemia
156
[Hyperparathyroidism / Hypoparathyroidism / Pseudohypoparathyroidism / Turner syndrome] can often be recognized clinically by the presence of shortened metacarpals, the so-called knuckle-knuckle-dimple-dimple sign.
119
| Pseudohypoparathyroidism; remember that knuckle-knuckle-dimple-knuckle is a sign of Turner syndrome.
157
____________________ results from decreased secretion of parathyroid hormone (PTH) or from decreased end-organ sensitivity to PTH.
120
| Hypoparathyroidism
158
_________________ reflects target organ insensitivity to PTH, and designates a group of hereditary conditions characterized by hypocalcemia.
121
Pseudohypoparathyroidism; In other words, pseudohypoparathyroidism is due to PTH insensitivity in the target organ- the cells can't 'see' PTH that is present.
159
Which ONE of the following is NOT a typical symptom/sign of hypoparathyroidism?
```
A. Paresthesias
B. Renal calculi
C. Tetany
D. Cataracts
E. Parkinsonian-like movement disorders due to calcification of the basal nuclei
F. Anxiety, depression, confusion
G. Increased intracranial pressure
H. (None; all of the above are typical symptoms/signs of hypoparathyroidism)
```
122
B. Incidentally, the paradoxical association of hypocalcemia with intracranial calcification may be due to increased phosphate levels, resulting in tissue deposits with locally produced calcium.
160
T/F Secondary hyperparathyroidism occurs in the context of chronic hypocalcemia.
123
| True; Usually this is due to kidney disease, but other factors- such as hypovitaminosis D- can cause it as well.
161
T/F Hyperparathyroidism is a rare disorder most common in young to middle-aged men.
124
False, false, false; Hyperparathyroidism is one of the most common endocrine disorders, occurring four times more often in women that men and typically occurring inolder adults (older 50 years of age).
162
T/F By far, the most common cause of hyperparathyroidism is a parathyroid carcinoma.
125
| False; The most common cause is a parathyroid adenoma. In fact, parathyroid carcinoma is downright rare.
163
T/F Hyperparathyroidism results in hypercalcemia.
126
| True; Remember, PTH raises blood calcium levels, so oversecretion of PTH....
164
T/F Classically, parathyroid adenoma involves all four glands, while parathyroid hyperplasia is almost always solitary .
127
False; This is backwards. Hyperplasia usually hits all four glands (or at least two or three) while parathyroid adenoma is solitary (as is carcinoma)..
165
T/F Some cases of secondary hyperparathyroidism respond to dietary vitamin D supplementation.
128
| True; If hypovitaminosis was the underlying cause of th secondary hypoparathyroidism.
166
__________________ refers to the syndrome caused by excessive secretion of PTH by a parathyroid adenoma, primary hyperplasia of all the parathyroids, or parathyroid carcinoma..
129
| Primary hyperparathyroidism
167
_________________ is caused by any condition that gives rise to chronic hypocalcemia, which in turn leads to compensatory overactivity of the parathyroid glands; it is encountered mainly in patients with chronic renal failure
130
Secondary hyperparathyroidism; Notice that low calcium levels stimulate the parathyroid glands just like TSH stimulates the thyroids.
168
T/F Primary hyperparathyroidism:
| Eroded bone matrix and osteoporosis
131A
True
'Painful bones'; PTH activates osteoclasts.
169
T/F Primary hyperparathyroidism:
| Kidney stones and nephrocalcinosis
131B
True
'Renal stones'
170
T/F Primary hyperparathyroidism:
| Metastatic calcification in body tissues
131C
True
Recall that metastatic calcification is due to high circulating levels of calcium.
171
T/F Primary hyperparathyroidism:
| Tetany
131D
False
Muscle spasms are more likely to occur with hypocalcemia.
172
T/F Primary hyperparathyroidism:
| Hypotension
131E
| False
173
T/F Primary hyperparathyroidism:
| Pancreatitis, cholelithiasis, constipation
131F
True
'Abdominal groans'
174
T/F Primary hyperparathyroidism:
| "Painful bones, renal stones, abdominal groans, and psychic moans"
131G
| True
175
T/F Primary hyperparathyroidism:
| Depression, lethargy, and eventually seizures
131H
True
'Psychic moans'.
176
T/F Primary hyperparathyroidism:
| Hyperactivity
131I
False
Weakness and fatigue are the norm, not hyperactivity.
177
T/F All steroid hormones are cholesterol derivatives.
132
| True; If it ain't derived from cholesterol, it can't be a steroid. Period.
178
T/F DHEA is the most important of the mineralocorticoids.
133
| False; DHEA is a gonadocorticoid; the most important mineralocorticoid is aldosterone.
179
Aldosterone is the most important of the [mineralocorticoids/ glucocorticoids/ gonadocorticoids].
134
| mineralocorticoids
180
[Mineralocorticoids/ Glucocorticoids/ Gonadocorticoids / Corticosteroids] are the primary steroid hormones made and released by adrenal cortex.
135
| Corticosteroids
181
The [mineralocorticoids / glucocorticoids/ gonadocorticoids ] are the corticosteroids that help regulate electrolyte balance.
136
| mineralocorticoids
182
The adrenal _______________ is the innermost part of the adrenal gland; it releases the sympathetic hormones epinephrine and norepinephrine.
137
| medulla
183
The adrenal ______________ is the outermost part of the adrenal gland; it releases the adrenal steroid hormones.
138
| cortex
184
Which of the following (may be more than one) does not trigger (i.e., stimulate) the renin-angiotensin-aldosterone system?
A. Decreased plasma sodium
B. Decreased red blood cell count (increased hypoxia)
C. Decreased plasma volume
D. Decreased plasma calcium
E. Decreased arterial blood pressure
F. Increased water retention
G. (None; all of the above stimulate the renin-angiotensin-aldosterone system)
139
B, D, F
B) The kidneys monitor oxygen carrying capacity of the blood, and release erythropoietin when it drops too low.
D) The parathyroid glands monitor plasma calcium levels and release PTH when it drops too low..
F) The hypothalamus monitors the hydration state of the blood and increases or decreases the secretion of ADH accordingly..
185
Which ONE of the following is not an effect of angiotensin II? Angiotensin II...
A. ...causes vasoconstriction of arteries.
B. ...acts on the hypothalamic thirst center to increase the sensation of thirst.
C. ...increases ADH secretion by the posterior pituitary, causing the kidneys to reabsorb more water.
D. ... increases aldosterone secretion by the adrenal cortex, causing the kidneys to reabsorb more sodium.
E. (None. All of the above are effects of angiotensin II)
140
| E. (None. All of the above are effects of angiotensin II)
186
Which ONE of the following is NOT an action of glucocorticoids like cortisol?
A. Glucocorticoids stimulate gluconeogenesis in liver cells.
B. Glucocorticoids promote glucose sparing.
C. Glucocorticoids lower blood glucose levels
D. Glucocorticoids promote protein and lipid breakdown
E. Glucocorticoids, at pharmacologic levels, suppress the immune system.
F. (None of the above, i.e., they are all true about glucocorticoids like cortisol)
141
C. As our stress hormones, glucocorticoids don't lower glucose levels- just the opposite, they raise them. The body is in a stressful situation, and glucocorticoids ensure that body cells at least have enough fuel- glucose- to deal with the stress.
187
T/F Pituitary disorders are the most common cause of secondary hyperaldosteronism.
143
False; Recall that the renin-angiotensin-aldosterone system is not controlled by the pituitary but by plasma sodium and blood volume/pressure. Thus, pituitary disoders do not directly cause secondary hyperaldosteronism.
188
T/F Seventy percent of cases of Conn syndrome are due to a hypersecreting tumor of the adrenal medulla.
144
False; Most instances of Conn tumor are due to a hypersecreting tumor of adrenal cortex. Medullary tumors would be pheochromocytomas.
189
T/F Aldosterone secretion is regulated by the pituitary hormone ACTH.
145
145. False; Under normal circumstances, ACTH has little to do with aldosterone secretion, which is regulated by the renin-angiotensin-aldosterone system.
190
T/F In contrast to Conn syndrome, secondary hyperaldosteronism is associated with hyperreninemia due to excessive activation of the renin-angiotensin-aldosterone system.
146
True; This forms a handy lab test to distinguish between primary and secondary hyperaldosteronism. Aldosterone and renin levels elevated- secondary hyperaldosteronism. Aldosterone elevated, renin normal- Conn syndrome.
191
T/F Hyperaldosteronism leads to enhanced activity of the Na+-K+ pumps in the kidney tubules, and usually results in hyponatremia and hyperkalemia.
147
False; This is almost correct, except the direction of the pumps. Sodium is pumped back INTO the body (from the urine), and potassium is pumped OUT of the body (into the urine). Thus hyperaldosteronism leads to hypernatremia and hypokalemia.
192
T/F Conn syndrome is often treated by administration of aldosterone.
148
False; Conn syndrome is primary hyperaldosteronism. Instead of treating it with aldosterone, you would treat it with an aldosterone antagonist, such as spironolactone.
193
[Primary/ Secondary] hyperaldosteronism is usually caused by conditions that reduce blood flow to the kidneys and thus excessive activation of the renin-angiotensin-aldosterone system.
149
| Secondary
194
In primary hyperaldosteronism, the renin-angiotensin-aldosterone system will be [suppressed / activated ] and plasma renin activity will be [ increased / decreased ].
150
RAA is suppressed and renin activity is decreased. This should make sense. If the purpose of the RAA system is to increase secretion of aldosterone, but aldosterone levels are already elevated, it makes sense that the RAA system would then be inhibited- 'We don't need no more stinkin' aldosterone!' Similarly, if renin activates the RAA system, but the RAA system is suppressed, then it makes sense that renin secretion will also be suppressed. 'We don't need no renin, either!'
195
Primary hyperaldosteronism is also known as ________________.
151
| Conn syndrome
196
_____________ is the most common manifestation of primary hyperaldosteronism.
152
| Hypertension, blood pressure elevation
197
Which ONE of the following is NOT a common symptom associated with
hyperaldosteronism?
```
A. HYPERTENSION
B. Hypernatremia
C. Hypokalemia
D. Muscle weakness
E. Hypercalcemia
F. Fatigue
G. Polyuria and polydipsia
H. Metabolic alkalosis
I. If hypokalemia, then paresthesias and even frank tetany
J. (None; all of the above are symptoms consistent with hyperaldosteronism)
```
153
| Hypercalcemia; aldosterone affects sodium and potassium, not calcium.
198
T/F The typical treatment for hypercortisolism is resection of a hypersecreting tumor, or cessation of glucocorticoid administration, whichever is appropriate.
154
| True
199
Cushing [disease/ syndrome] refers to hypercortisolism due to a pituitary corticotropic adenoma.
155
| Disease; all other causes of hypercortisolism is refered to as Cushing syndrome.
200
___________________ refers to elevated blood sugar levels as a result of hypercortisolism.
156
| Adrenal diabetes
201
Which ONE of the following is the most common cause of Cushing syndrome?
A. Pituitary corticotropic adenoma (ACTH hypersecretion)
B. Exogenous glucocorticoids such as prednisone
C. Functional adrenocorticotropic tumors
D. Paraneoplasty; functional extrapituitary tumors that hypersecrete ACTH
H. (None; the most common cause of Cushing syndrome is not listed above)
157
B; Amongst all causes, the most common cause is ingestion or absorption of glucocorticoid drugs. Amongst just the endogenous causes, the most common is a pituitary corticotropic adenoma.
202
Which of the following is NOT a typical manifestation of Cushing syndrome?
A. "Buffalo hump" in the lower neck/upper back region
B. "Moon face"
C. Low resistance to infections
D. Cutaneous striae, dermal atrophy
E. Menstrual irregularities
F. Hypoglycemia, oliguria
G. (None; all of the above are typical manifestations of Cushing syndrome).
158
F. Because of the diabetogenic effect of cortisol, Cushing syndrome cause hyperglycema, from which come glycosuria, polyuria, and polydipsia. The low resistance to infections is due to the fact the high levels of glucocorticoids suppresses the immune system.
203
T/F The most common cause of adrenogenital syndrome in adult women is an androgen-producing tumor.
159
| True
204
T/F In neonates, adrenogenital syndrome is typically caused by mutation of one of the enzymes involved in steroid metabolism.
160
True; This is known as congenital adrenal hyperplasia. The hyperplasia is due to a chain of events, starting with low cortisol levels, which then cause high ACTH levels, which in turn stimulates the adrenal glands and results in hyperplasia.
205
__________________ is a condition in which hypersecretion of adrenal sex steroids (androgens) leads to masculinization in girls and precocious pseudopuberty in boys.
161
| Adrenogenital syndrome
206
In _______________ adrenogenital syndrome (or congenital adrenal hyperplasia), a total lack of 21-hydroxylase activity results in no synthesis of either cortisol or aldosterone; such an individual cannot retain their sodium.
162
| Salt-wasting; this manifestation of adrenogenital syndrome kills babies (dehydration, electrolyte imbalances).
207
________________ adrenogenital syndrome (AS) (or congenital adrenal hyperplasia), the most common type of AS, is due to partial deficiency of 21-hydroxylase activity; such indiviuals can still make cortisol and aldosterone, though at lower levels than normal.
163
| Late-onset; this form of AS may be asymptomatic, or may present as hirsutism and menstrual irregularities.
208
Adrenogenital syndrome causes ___________________ in boys.
164
| Precocious pseudopuberty
209
Adrenogenital syndrome causes ___________________ in girls.
165
| Virilization
210
Which ONE of the following statements best describes the steroid deficiency or deficiencies accompanying a total lack of 21 hydroxylase activity?
```
A. Cortisol and aldosterone
B. Cortisol only
C. Cortisol and progesterone
D. Progesterone and estrogens
E. Testosterone and estrogen
F. Progesterone, estrogen, and testosterone
G. All corticosteroids
H. (None. Corticosteroid synthesis is not affected by a lack of 21 hydroxylase)
```
166
A. Cortisol and aldosterone. Examine the steroid biosynthesis chart on or about Slide 161. Recall that many mutations can alter 21 hydroxylase activity. If a patient has NO hydroxylase activity, then they will have extreme hypocortisolism with salt wasting (lack of aldosterone)- a very serious medical condition. On the other hand, some hydroxylase mutations will abolish cortisol synthesis but leave adequate aldosterone sythesis. Such individuals will experience hypocortisolism without the salt-wasting. In either case, lack of cortisol (with or without lack of aldosterone) shunts adrenal resources into gonadocorticoid synthesis, resulting in adrenogenital syndrome.
211
Which ONE of the following is not a symptom/sign consistent with late-onset congenital adrenal hyperplasia?
```
A. 21 hydroxylase deficiency
B. Delayed menarche
C. Oligomenorrhea
D. Hirsutism
E. Truncal obesity and moon face
F. (None. All of the above are consistent with congenital adrenal hyperplasia)
```
167
E. Recall that in CAH, cortisol levels are down, whereas truncal obesity and moon face are seen in hypercortisolism. Thus they would not be present in CAH. Also, while several other enzyme deficiencies could be the cause of CAH (such as 11
hydroxylase), a 21 hydroxylase is by far the most common enzyme that is lacking.
212
Unless antibiotic therapy is instituted immediately, Waterhouse-Friderichsen Syndrome may kill within hours to a few days.
168
| True
213
Addison disease progresses quickly, and when about 50% of the adrenal cortex (of both glands) is lost, it becomes clinically apparent.
169
False; This is a chronic disease, which takes a chronic, slowly progressive course. About 90% of the adrenal cortex needs to be lost before this disorder becomes clinically apparent.
214
Both primary and secondary adrenocortical insufficiency usually result in hyperpigmentation.
170
False; The hyperpigmentation comes from the link between high ACTH and high MSH and POMC levels. Except that in secondary adrenocortical insufficiency ACTH levels are depressed, so that SAI would not lead to hyperpigmentation.
215
Another distinction between primary (PAI) and secondary (SAI) adrenocortical insufficiency is that aldosterone levels are depressed in the former (PAI) but (near) normal in the latter (SAI).
171
True; Recall that PAI is due to adrenocortical destruction, while SAI is due to low ACTH levels. Recall also that ACTH largely controls cortisol, and to a lesser extent, gonadocorticoid levels, while the renin-angiotensin-aldosterone system controls aldosterone levels. In PAI, where the adrenal cortex is being destroyed, ALL corticosteroid levels will be down, whereas in in SAI, the low ACTH will depress cortisol and gonadocorticoid levels but leave aldosterone levels relatively untouched.
216
__________________, or primary acute adrenocortical insufficiency, is acute,
bilateral, hemorrhagic infarction of the adrenal cortex, most commonly secondary to meningococcal or pseudomonal septicemia.
172
Waterhouse-Friderichsen syndrome; this may not become symptomatic until 90% of the adrenals are destroyed, and even today it still kills many of its victims.
217
_______________, or primary chronic adrenocortical insufficiency, is marked by progressive destruction of the adrenal cortex, usually by autoimmune phenomena.
173
Addison disease; Although autoimmune adrenalitis is the most common cause of Addison disease, any process that slowly destroys the adrenal cortex, such as infection, can cause this disorder.
218
Which ONE of the following is NOT a symptom consistent with Waterhouse-Friderichsen syndrome.
A. Rapidly progressing hypotension
B. Shock
C. Disseminated intravascular coagulopathy
D. Widespread purpura
E. (None; all of the above are symptoms of Waterhouse-Friderichsen syndrome)
174
| E. This is a very serious syndrome, and without immediate antibiotic therapy it may kill within hours or a few days.
219
Which ONE of the following is NOT a symptom commonly associated with Addison disease?
```
A. GI disturbances such as diarrhea and nausea
B. Weakness and easy fatigability
C. Hyperpigmentation
D. Hypernatremia and hypokalemia
E. Hypovolemia and hypotension
F. Poor resistance to stress
G. Cardiac conduction problems
H. (None of the above, i.e., they are all true about the symptoms of Addison disease)
```
175
D. Remember that aldosterone conserves sodium at the expense of potassium. In adrenocortical insufficiency, aldosterone levels are deficient, which will thus result in hyponatremia and hyperkalemia.
Notes:
(b) Probably due to the electrolyte disturbances, such as low sodium and high potassium.
(c) Due to the MSH, ACTH, and POMC connection.
(d) Due to the low aldosterone levels.
(e) Again due to the low aldosterone levels.
(f) Due to the low cortisol levels.
(g) Due to the electrolyte imbalances.
220
Which ONE of the following is a valid distinction between primary (PAI) vs secondary (SAI) adrenocortical insufficiency?
A. In PAI cortisol levels are elevated while in SAI cortisol levels are depressed.
B. In PAI and SAI, ACTH levels are depressed.
C. Exogenously administered ACTH would raise cortisol levels in SAI but not in PAI
D. Exogenously administered cortisol would raise ACTH levels in PAI but not in SAI
E. Lowered blood sodium levels would activate the renin-angiotensin-aldosterone system and ultimately raise aldosterone levels in PAI
F. ACTH has no effect on the adrenals in either PAI or SAI.
G. (None. None of the above statements are a valid distinction between PAI and SAI)
176
C. For the explanations given below, keep in mind that PAI is slow destruction of the adrenal cortex, and ACTH cannot stimulate a cortex that has been lost. SAI, on the other hand, is a problem with the pituitary secretion of ACTH; the adrenals are healthy but are not receiving enough ACTH.
Notes:
(a) We are talking adrenocortical insufficiency- cortisol levels are depressed in both PAI and SAI.
(b) ACTH levels are depressed in SAI, but elevated in PAI (the pituitary is trying in vain to stimulate adrenals that are mostly destroyed).
(c) Remember again that the problem is low ACTH in SAI, so giving ACTH would raise cortisol levels. On the other hand, adrenal destruction has occurred in PAI, so raising ACTH levels won't accomplish diddly-squat.
(d) In either case, cortisol has a negative feedback effect on ACTH, so raising cortisol levels by injection would only serve to lower ACTH levels.
(e) This might seem true at first, since low sodium is a trigger for the RAA system. But again, we are talking primary adrenocortical insufficiency here, and angiotensin II cannot squeeze aldosterone out of destroyed adrenals anymore than you can squeeze water out of a hard rock (I think that analogy works here).
(f) ACTH would raise cortisol levels in SAI.
221
T/F The sine qua non of a pheochromocytoma is the elevated levels of epinephrine and norepinephrine.
177
True; Remember that sine qua non means, '(That) without which there is no other', meaning you will not have a pheochromocytoma of any size without elevated E/NE levels.
222
T/F Most pheochromocytomas are benign.
178
| True; About 90% actually
223
A ____________________ is a hyperfunctional tumor of the chromaffin cells of the adrenal medulla.
179
| pheochromocytoma
224
Which ONE of the following is NOT a symptom consistent with a tumor of the chromaffin cells of the adrenal medulla?
```
A. Hyperglycemia
B. Increased metabolic rate
C. Rapid heart beat and palpitations
D. Hypertension
E. Intense nervousness
F. Anhidrosis
G. (None of the above, i.e., they are all true about chromaffin cell tumors of the adrenal medulla)
```
180
F. All except anhidrosis are simply symptoms of increased sympathetic activity. Sweating is a sympathetic phenomenon, so anhidrosis- lack of sweating- would not be consistent with the heightened sympathetic activity of these tumors.
225
T/F Type II diabetes mellitus responds well to a lifetime of insulin injections.
181
False; insulin levels may very well be normal in NIDDM; the problem is that target cells cannot respond properly to insulin, so injecting more insulin will not help. To be more precise, it may help initially, by flooding the body with so much insulin that it overcomes the hyporesponsiveness, but eventually the target cells stop responding to these high insulin levels, at which point further insulin injections will be of little help.
226
T/F Glucagon targets the liver, muscles, and adipose tissue.
182
| False; Glucagon targets the liver; insulin would target all these organs, and more.
227
T/F In the endocrine pancreas, alpha cells secrete insulin and beta cells secrete glucagon.
183
| False; It's the other way around.
228
Normally, [hypoglycemia/ hyperglycemia] results from hypersecretion of insulin.
184
| hypoglycemia; remember that glucose brings the blood sugar- and other fuels- down in concentration.
229
____________ and ____________ are the two primary mechanisms by which the high blood sugar of diabetes mellitus damages tissues around the body.
185
| Nonenzymatic glycosylation and osmotic damage
230
______________, some of which are strong organic acids, are created when fats are metabolized without adequate levels of carbohydrates.
186
Ketones, or ketone bodies. Acetone and acetoacetic acid are two examples. These are commonly created in diabetes mellitus, where adequate sugar (carbohydrate) is not imported into cells.
231
Which ONE of the following is not a common symptom of hypoglycemia?
```
A. Tremulousness, weakness
B. Headache and confusion
C. Hunger, nervousness
D. Decreased sweating and bradycardia
E. Slurred speech
F. (None; all of the above are symptoms consistent with hypoglycemia)
```
187
D. The symptoms of hypoglycemia listed in this question are either due to reflexive activation of sympathetic nervous system caused by the hypoglycemia or to insufficient glucose to the brain. Decreased sweating and bradycardia are not
sympathetic effects- increased sweating and tachycardia are. Thus D is the incorrect answer.
232
Which ONE of the following is NOT a symptom of diabetes mellitus?
A. Polyuria and dehydration
B. Polydipsea
C. Electrolyte imbalances
D. Polyphagia
E. Appearance of ketone bodies in the blood
F. Lipidemia
G. (None, i.e., all of the above are symptoms of diabetes mellitus)
188
| G. (None, i.e., all of the above are symptoms of diabetes mellitus)
233
Which ONE of the following is NOT TRUE of Type I diabetes mellitus (IDDM)?
A. IDDM is the less common form of diabetes mellitus
B. IDDM appears to be an autoimmune disease and is characterized by loss of insulin-secreting beta cells in the pancreas
C. Blood insulin levels are typically quite low in IDDM individuals
D. IDDM can be managed with life-long insulin injections
E. IDDM is also known as juvenile onset diabetes
F. IDDM is only found in juveniles
G. (None, i.e., all of the above are true of Type I diabetes mellitus)
189
| F. Altho IDDM has a predilection for younger individuals, it can (and does) appear at any age, even in the elderly.
234
Which ONE of the following is NOT TRUE of Type II diabetes mellitus (NIDDM)?
A. NIDDM is the more common form of diabetes mellitus
B. The insulin hyporesponsiveness of NIDDM extends to all cells in the body; all cells are essentially starved for glucose
C. NIDDM may involve problems with the insulin receptors themselves, or perhaps with intracellular processes occurring after receptor activation
D. Because of insulin hyporesponsiveness, target cells cannot respond properlyto insulin and internalize glucose
E. NIDDM involves insulin resistance: target cells do not respond adequately to insulin
F. In NIDDM, target cells are effectively starved for glucose even tho blood levels of glucose are high
G. NIDDM responds well to dietary restriction and exercise
H. (None, i.e., all of the above are true of Type II diabetes mellitus)
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B. Remember that insulin only affects the up-regulation of the GLUT4 glucose transporter; cells (such as brain cells) that use other GLUT transporters will not respond to insulin under any circumstances. This makes sense, since brain cells need constant access to glucose, and could not tolerate having access at some times (high insulin) and not at other times (low insulin) to blood glucose.
