Pathophysiology Chap 32
A lung cancer client with small cell carcinoma may secrete an excess of which hormone causing an ectopic form of Cushing syndrome due to a nonpituitary tumor? Select one: A. ACTH B. GH C. DHEA D. TSH
A. ACTH The third form (of Cushing syndrome) is ectopic Cushing syndrome, caused by a nonpituitary ACTH-secreting tumor. Certain extra pituitary malignant tumors such as small cell carcinoma of the lung may secrete ACTH or, rarely, CRH and produce Cushing syndrome. The adrenal sex hormone dehydroepiandrosterone (DHEA) contributes to the pubertal growth of body hair, particularly pubic and axillary hair in women. Thyroid-stimulating hormone (TSH) levels are used to differentiate between primary and secondary thyroid disorders. Although secretion of growth hormone (GH) has diurnal variations over a 24-hour period, with nocturnal sleep bursts occurring 1 to 4 hours after onset of sleep, it is unrelated to ACTH and/or CRH secretion.
The signs and symptoms of abrupt cessation of pharmacologic glucocorticoids closely resemble those of: Select one: A. Addison disease B. Cushing disease C. Cushing syndrome D. Graves disease
A. Addison disease Although the etiology differs, the adrenal cortical insufficiency resulting from the abrupt cessation of glucocorticoids is nearly identical to Addison disease in terms of physiologic effects.
One of the first signs that indicates an infant may have congenital hypothyroidism is: Select one: A. Prolonged period of physiologic jaundice B. No passage of meconium within the first 72 hours after birth C. Palpable mass in the neck region D. Full, bounding fontanels
A. Prolonged period of physiologic jaundice With congenital lack of the thyroid gland, the infant usually appears normal and functions normally at birth because of hormones supplied in utero by the mother. Prolongation of physiologic jaundice, caused by delayed maturation of the hepatic system for conjugating bilirubin, may be the first sign. There may be respiratory difficulties and a hoarse cry, feeding difficulties, and an enlarged abdomen. This condition will not interfere with meconium passage, elevated ICP resulting in full, tight fontanels, or having a palpable mass in the neck.
Primary adrenal insufficiency is manifested by: Select one: A. Serum sodium level of 120 mmol/L (low) and blood glucose level of 48 mg/dL (low) B. Hypopigmentation over neck and BP greater than 150/90 C. Truncal obesity and 3+ pitting edema in lower legs D. Potassium level of 2.8 mEq/L and weight gain of 3 pounds overnight
A. Serum sodium level of 120 mmol/L (low) and blood glucose level of 48 mg/dL (low) Primary adrenal insufficiency is adrenal cortical hormone deficiency with elevated adrenocorticotropic hormone (ACTH) levels caused by a lack of feedback inhibition. Manifestations are related primarily to mineralocorticoid deficiency, causing increased urinary losses of sodium, chloride, and water, along with decreased excretion of potassium. The result is hyponatremia, loss of extracellular fluid, decreased cardiac output, and hyperkalemia. Because of a lack of glucocorticoid, the person with Addison disease has poor tolerance to stress. This deficiency causes hypoglycemia, lethargy, weakness, fever, and gastrointestinal symptoms such as anorexia, nausea, vomiting, and weight loss. Hypopigmentation results from elevated ACTH levels.
A client has developed the facial appearance that is characteristic of myxedema, along with an enlarged tongue, bradycardia, and voice changes. Which of the following treatment modalities is most likely to benefit this client? Select one: A. Synthetic preparations of T3 or T4 B. Oral or parenteral cortisol replacement C. Corticosteroid replacement therapy D. β-Adrenergic blocking drugs
A. Synthetic preparations of T3 or T4 Myxedema and the client's other signs are associated with hypothyroidism, which necessitates thyroid hormone replacement. β-Adrenergic blocking drugs and antithyroid drugs are indicated in the treatment of hyperthyroidism, whereas treatments relevant to adrenal cortical function are not relevant to hypothyroidism.
Which of the following individuals is experiencing the effects of a primary endocrine disorder? A client: Select one: A. Who has low calcium levels because of the loss of his parathyroid gland B. Whose dysfunctional hypothalamus has resulted in endocrine imbalances C. With adrenal cortical insufficiency due to pituitary hyposecretion of ACTH D. Who has hypothyroidism as a result of low TSH production
A. Who has low calcium levels because of the loss of his parathyroid gland The loss of a gland, and the subsequent absence of the hormone that it normally produces, results in a primary endocrine disorder. The lack of a stimulating hormone such as ACTH or TSH results in a secondary disorder, whereas hypothalamic dysfunction causes tertiary endocrine disorders.
Which of the following physiologic processes is a direct effect of the release of growth hormone by the anterior pituitary? Select one: A. Increase in overall metabolic rate and cardiovascular function B. Production of insulin-like growth factors (IGFs) by the liver C. Positive feedback of the hypothalamic-pituitary-thyroid feedback system D. Development of cartilage and bone
B. Production of insulin-like growth factors (IGFs) by the liver GH cannot directly produce bone growth; instead, it acts indirectly by causing the liver to produce IGFs. It affects neither metabolic rate nor the function of the hypothalamic-pituitary-thyroid feedback system.
Which of the following individuals displays the precursors to acromegaly? Select one: A. A client who has recently developed primary adrenal carcinoma B. An adult with an excess of growth hormone due to an adenoma C. An adult who has a diagnosis of Cushing syndrome D. A girl who has been diagnosed with precocious puberty
B. An adult with an excess of growth hormone due to an adenoma When growth hormone (GH) excess occurs in adulthood or after the epiphyses of the long bones have fused, it causes a condition called acromegaly, which represents an exaggerated growth of the ends of the extremities.
A 33-year-old client has been admitted to the hospital for the treatment of Graves disease. Which of the following assessments should the client's care team prioritize? Select one: A. Cardiac monitoring and assessment of peripheral perfusion B. Assessment of the client's vision and oculomotor function C. Assessment of the client's level of consciousness and neurologic status D. Assessment of the client's peripheral vascular system for thromboembolism
B. Assessment of the client's vision and oculomotor function Ophthalmopathy occurs in a large proportion (up to one third) of clients with Graves disease and may result in permanent vision damage. This supersedes the importance of cardiac, neurologic, and peripheral vascular assessments, although these assessments are relevant to the broader effects of hyperthyroidism that the client may likely experience.
The most common cause of thyrotoxicosis is Graves disease. When assessing this client, the nurse should put priority on which of the following signs/symptoms? Select one: A. Complaints of muscle fatigue B. Ophthalmopathy C. Pulse rate of 64 beats/minute D. Facial myxedema with puffy eyelids
B. Ophthalmopathy Graves disease is characterized by a triad of hyperthyroidism, goiter, ophthalmopathy (exophthalmos), or less commonly, dermopathy (pretibial edema due to accumulation of fluid and glycosaminoglycans). Even in persons without exophthalmos (i.e., bulging of the eyeballs seen in ophthalmopathy), there is an abnormal retraction of the eyelids and infrequent blinking such that they appear to be staring. Although the myxedema of hypothyroidism is most obvious in the face and other superficial parts, it also affects many of the body organs. Common to all types of thyrotoxicosis, rather than unique to Graves disease, cholesterol blood levels are decreased; muscle proteins are broken down and used as fuel, which accounts for the muscle fatigue that occurs with all types of hyperthyroidism.
When educating a client with possible glucocorticoid dysfunction, the nurse will explain that the CRH controls the release of ACTH. The best time to perform the blood test to measure peak ACTH levels would be: Select one: A. 09:00 to 11:00 PM B. 10:00 to 12:00 AM C. 06:00 to 08:00 AM D. 04:00 to 6:00 PM
C. 06:00 to 08:00 AM Levels of cortisol increase as ACTH levels rise and decrease as ACTH levels fall. There is considerable diurnal variation in ACTH levels, which reach their peak in the early morning (around 6 to 8 AM) and decline as the day progresses.
Which of the following pathophysiologic phenomena may result in a diagnosis of Cushing disease? Select one: A. Autoimmune destruction of the adrenal cortex B. Malfunction of the HPA system C. Excess ACTH production by a pituitary tumor D. Hypopituitarism
C. Excess ACTH production by a pituitary tumor Three important forms of Cushing syndrome result from excess glucocorticoid production by the body. One is a pituitary form, which results from excessive production of ACTH by a tumor of the pituitary gland. Hypopituitarism and destruction of the adrenal cortex are associated with Addison disease. Disruption of the HPA system is not implicated in the etiology of Cushing disease.
The immune suppressive and anti-inflammatory effects of cortisol cause: Select one: A. Increased capillary permeability B. Moderate insulin resistance C. Inhibition of prostaglandin synthesis D. Increased cell-mediated immunity
C. Inhibition of prostaglandin synthesis Large quantities of cortisol are required for an effective anti-inflammatory action. The increased cortisol blocks inflammation at an early stage by decreasing capillary permeability and stabilizing the lysosomal membranes so that inflammatory mediators are not released. Cortisol suppresses the immune response by reducing humoral and cell-mediated immunity. Cortisol also inhibits prostaglandin synthesis, which may account in large part for its anti-inflammatory actions. Cortisol stimulates glucose production by the liver; as glucose production by the liver rises and peripheral glucose use falls, a moderate resistance to insulin and hyperglycemia develop.
The iatrogenic form of Cushing syndrome is caused by: Select one: A. Ectopic ACTH-secreting lung tumor B. Pituitary tumor secreting ACTH C. Long-term cortisone therapy D. Benign or malignant adrenal tumor
C. Long-term cortisone therapy Three important forms of Cushing syndrome result from excess glucocorticoid production by the body. One is a pituitary form, which results from excessive production of ACTH by a tumor of the pituitary gland, called Cushing disease. The second form is the adrenal form, caused by a benign or malignant adrenal tumor. The third form is ectopic Cushing syndrome, caused by a nonpituitary ACTH-secreting tumor, often carcinoma of the lung. Iatrogenic Cushing syndrome results from long-term therapy with one of the potent pharmacologic preparations of glucocorticoids.
Which of the following residents of a long-term facility is exhibiting clinical manifestations of hypothyroidism? Select one: A. A 90-year-old woman with a history of atrial fibrillation whose arrhythmia has recently become more severe B. An 88-year-old man with a history of Alzheimer disease who has become increasingly agitated and is wandering around the facility more frequently C. A 91-year-old man with a chronic venous ulcer and a sacral ulcer who has developed sepsis D. An 80-year-old woman who has uncharacteristically lost her appetite and often complains of feeling cold
D. An 80-year-old woman who has uncharacteristically lost her appetite and often complains of feeling cold Loss of appetite and cold intolerance are characteristic symptoms of hypothyroidism. Arrhythmias, agitation, and infections are not typically associated with hypofunction of the thyroid gland.
A client who has been taking 80 mg of prednisone, a glucocorticoid, each day has been warned by his primary care provider to carefully follow a plan for the gradual reduction of the dose rather than stopping the drug suddenly. What is the rationale for this directive? Select one: A. Sudden cessation of a glucocorticoid can result in adrenal gland necrosis. B. Stopping the drug suddenly may "shock" the HPA axis into overactivity. C. Sudden changes in glucocorticoid dosing may reverse the therapeutic effects of the drug. D. Stopping the drug suddenly may cause acute adrenal insufficiency.
D. Stopping the drug suddenly may cause acute adrenal insufficiency. Chronic suppression of the HPA system by the use of steroids causes atrophy of the adrenal gland, and the abrupt withdrawal of drugs can cause acute adrenal insufficiency. Activity of the HPA system is consequently insufficient. The efficacy of the drug is not the primary concern, and necrosis of the gland itself does not occur.
