questions - Drug therapy for pituitary and hypothalamic dysfunction

Which of the following hormones directly acts on target tissues without stimulating the production of other hormones?

A) Corticotropin (ACTH)

B) Growth hormone (GH)

C) Follicle-stimulating hormone (FSH)

D) Luteinizing hormone (LH)

Answer: B) Growth hormone (GH)

Rationale:

GH acts directly on target tissues to promote growth and metabolism.

ACTH, FSH, and LH stimulate target tissues to produce other hormones, while GH does not.

Incorrect Options:

A) Corticotropin (ACTH): Stimulates adrenal glands to produce cortisol.

C) Follicle-stimulating hormone (FSH): Stimulates the growth of ovarian follicles and sperm production.

D) Luteinizing hormone (LH): Stimulates ovulation and testosterone production.

Which hormone is primarily responsible for making renal tubules more permeable to water, leading to the reabsorption of more water and less urine output?

A) Corticotropin (ACTH)

B) Growth hormone (GH)

C) Antidiuretic hormone (ADH)

D) Thyrotropin (TSH)

Answer: C) Antidiuretic hormone (ADH)

Rationale:

ADH, also known as vasopressin, acts on the kidneys to increase water reabsorption, reducing urine output.

Corticotropin, GH, and TSH do not directly affect water reabsorption.

Incorrect Options:

A) Corticotropin (ACTH): Stimulates the adrenal glands to produce cortisol.

B) Growth hormone (GH): Promotes growth and metabolism.

D) Thyrotropin (TSH): Stimulates the thyroid gland to produce thyroid hormones.

Which hormone functions primarily in childbirth by initiating contractions and causing the release of milk from mammary glands?

A) Prolactin

B) Thyrotropin (TSH)

C) Oxytocin

D) Melanocyte-stimulating hormone (MSH)

Answer: C) Oxytocin

Rationale:

Oxytocin is responsible for uterine contractions during childbirth and milk letdown during breastfeeding.

Prolactin stimulates milk production but does not initiate contractions.

Thyrotropin stimulates the thyroid gland, and MSH regulates skin pigmentation.

Incorrect Options:

A) Prolactin: Stimulates milk production but does not directly cause contractions.

B) Thyrotropin (TSH): Stimulates the thyroid gland.

D) Melanocyte-stimulating hormone (MSH): Regulates skin pigmentation.

Which type of hormone directly regulates target tissues by acting on them without stimulating the production of other hormones?

A) Hypothalamic Hormones

B) Posterior Pituitary Hormones

C) Anterior Pituitary Hormones

D) Growth Hormone (GH) Releasing Hormone

Answer: C) Anterior Pituitary Hormones

Rationale:

Anterior pituitary hormones, such as GH and prolactin, act directly on target tissues without stimulating the production of other hormones.

Hypothalamic hormones regulate anterior pituitary hormones, while posterior pituitary hormones mainly consist of nerve fibers.

GH releasing hormone is a type of hypothalamic hormone.

Incorrect Options:

A) Hypothalamic Hormones: Regulate anterior pituitary hormones.

B) Posterior Pituitary Hormones: Mainly consist of nerve fibers.

D) Growth Hormone (GH) Releasing Hormone: Stimulates the release of GH from the anterior pituitary.

Which pituitary disorder is characterized by excessive secretion of growth hormone, leading to abnormal growth of bones and tissues?

A) Diabetes Insipidus

B) Acromegaly

C) Growth Hormone Deficiency

D) Precocious Puberty

Answer: B) Acromegaly

Rationale:

Acromegaly results from excessive secretion of growth hormone in adulthood, leading to abnormal growth of bones and tissues, particularly in the face, hands, and feet.

Diabetes Insipidus results from dysfunction in the posterior pituitary's secretion of ADH.

Growth hormone deficiency is characterized by insufficient secretion of growth hormone.

Precocious puberty involves early maturation of the hypothalamic–pituitary–gonadal axis.

Incorrect Options:

A) Diabetes Insipidus: Characterized by excessive urination and thirst due to inadequate ADH secretion.

C) Growth Hormone Deficiency: Characterized by insufficient secretion of growth hormone, leading to growth abnormalities.

D) Precocious Puberty: Involves early maturation of the reproductive system.

Which treatment modality is commonly used for acromegaly when surgery or radiation therapy is not effective?

A) Radiation therapy

B) Pegvisomant (Somavert)

C) Administration of growth hormone (somatropin)

D) Carpal tunnel release surgery

Answer: B) Pegvisomant (Somavert)

Rationale:

Pegvisomant is a growth hormone receptor antagonist used to treat acromegaly by blocking the effects of excessive growth hormone.

Radiation therapy may be used as an alternative treatment but is not the first choice after surgery.

Administration of growth hormone (somatropin) is used to treat growth hormone deficiency, not acromegaly.

Carpal tunnel release surgery addresses a symptom of acromegaly (carpal tunnel syndrome) but does not treat the underlying hormonal imbalance.

Incorrect Options:

A) Radiation therapy: Used primarily when surgery is not effective for pituitary adenomas.

C) Administration of growth hormone (somatropin): Used for growth hormone deficiency, not acromegaly.

D) Carpal tunnel release surgery: Addresses a symptom but does not treat the underlying cause of acromegaly.

Which adverse effect is commonly associated with the administration of growth hormone for treatment?

A) Hypoglycemia

B) Antibody formation against growth hormone

C) Increased appetite

D) Reduced risk of carpal tunnel syndrome

Answer: B) Antibody formation against growth hormone

Rationale:

Antibodies against growth hormone can develop with prolonged use, reducing the effectiveness of treatment.

Hyperglycemia (not hypoglycemia) is a common adverse effect of growth hormone treatment.

Growth hormone administration can increase appetite, leading to weight gain, not reducing it.

Growth hormone treatment can exacerbate carpal tunnel syndrome symptoms rather than reducing the risk.

Incorrect Options:

A) Hypoglycemia: Growth hormone treatment typically leads to hyperglycemia.

C) Increased appetite: Common side effect of growth hormone treatment.

D) Reduced risk of carpal tunnel syndrome: Growth hormone treatment can worsen carpal tunnel syndrome symptoms.

In which patient population is growth hormone treatment contraindicated due to increased risk of fatality?

A) Patients with acromegaly

B) Patients with growth hormone deficiency

C) Patients with Prader-Willi syndrome (PWS)

D) Patients with carpal tunnel syndrome

Answer: C) Patients with Prader-Willi syndrome (PWS)

Rationale:

Growth hormone treatment can exacerbate obesity and obstructive sleep apnea (OSA) in patients with Prader-Willi syndrome, potentially leading to fatal outcomes.

Acromegaly and growth hormone deficiency are conditions that may require growth hormone treatment.

Carpal tunnel syndrome is a complication of acromegaly but is not a contraindication to growth hormone treatment.

Incorrect Options:

A) Patients with acromegaly: Growth hormone treatment is often used to treat acromegaly.

B) Patients with growth hormone deficiency: Growth hormone treatment is indicated for patients with growth hormone deficiency.

D) Patients with carpal tunnel syndrome: Carpal tunnel syndrome may be a symptom of acromegaly but is not a contraindication to growth hormone treatment.

Which hormone opposes the effects of growth hormone?

A) Thyroid hormone

B) Insulin-like growth factor 1 (IGF-1)

C) Glucocorticoids

D) Prolactin

Answer: C) Glucocorticoids

Rationale:

Glucocorticoids counteract the effects of growth hormone by promoting the breakdown of proteins and inhibiting protein synthesis.

Thyroid hormone and IGF-1 work in conjunction with growth hormone to regulate growth and metabolism.

Prolactin is involved in lactation and does not directly oppose the effects of growth hormone.

Incorrect Options:

A) Thyroid hormone: Works in conjunction with growth hormone to regulate metabolism but does not oppose its effects.

B) Insulin-like growth factor 1 (IGF-1): Produced in response to growth hormone and mediates many of its effects.

D) Prolactin: Stimulates milk production and does not directly oppose the effects of growth hormone.

What is the primary mechanism of action of pegvisomant (Somavert) in the treatment of acromegaly?

A) Inhibiting the production of growth hormone

B) Blocking the effects of growth hormone

C) Stimulating the release of insulin-like growth factor 1 (IGF-1)

D) Inducing apoptosis of pituitary adenoma cells

Answer: B) Blocking the effects of growth hormone

Rationale:

Pegvisomant is a growth hormone receptor antagonist that blocks the effects of excessive growth hormone by binding to its receptors.

It does not inhibit the production of growth hormone but rather prevents its action on target tissues.

Pegvisomant does not directly stimulate the release of IGF-1 or induce apoptosis of pituitary adenoma cells.

Incorrect Options:

A) Inhibiting the production of growth hormone: This is not the mechanism of action of pegvisomant.

C) Stimulating the release of insulin-like growth factor 1 (IGF-1): Pegvisomant does not stimulate IGF-1 release.

D) Inducing apoptosis of pituitary adenoma cells: Pegvisomant does not induce apoptosis but rather blocks growth hormone receptors.

What is the primary pharmacodynamic action of somatropin?

A) Inhibiting skeletal growth

B) Stimulating cartilage growth at the epiphyseal plate

C) Decreasing muscle mass

D) Inducing fat deposition

Answer: B) Stimulating cartilage growth at the epiphyseal plate

Rationale:

Somatropin stimulates the growth of cartilage at the epiphyseal plates, leading to skeletal growth.

Inhibition of skeletal growth, decreasing muscle mass, and inducing fat deposition are not primary actions of somatropin.

Incorrect Options:

A) Inhibiting skeletal growth: Contrary to the pharmacodynamic action of somatropin.

C) Decreasing muscle mass: Contrary to the pharmacodynamic action of somatropin.

D) Inducing fat deposition: Contrary to the pharmacodynamic action of somatropin.

In which condition is the use of somatropin contraindicated due to the risk of closed epiphyses?

A) Growth hormone deficiency

B) Prader-Willi syndrome

C) Noonan’s syndrome

D) Acute critical illness

Answer: A) Growth hormone deficiency

Rationale:

Somatropin is contraindicated in conditions where epiphyses are closed, such as growth hormone deficiency.

Prader-Willi syndrome and Noonan’s syndrome may still have open epiphyses, making somatropin potentially beneficial.

Acute critical illness and underlying intracranial lesions are contraindications due to other reasons.

Incorrect Options:

B) Prader-Willi syndrome: Epiphyses may still be open in patients with this syndrome.

C) Noonan’s syndrome: Epiphyses may still be open in patients with this syndrome.

D) Acute critical illness: Contradicted due to other reasons, not closed epiphyses.

Which adverse effect is commonly associated with somatropin administration?

A) Hypoglycemia

B) Bradycardia

C) Mild edema

D) Hypertension

Answer: C) Mild edema

Rationale:

Mild edema is a common adverse effect of somatropin administration.

Hypoglycemia is not commonly associated with somatropin but rather hyperglycemia.

Bradycardia and hypertension are not typical adverse effects of somatropin.

Incorrect Options:

A) Hypoglycemia: Contrary to the typical adverse effect profile of somatropin.

B) Bradycardia: Not a typical adverse effect of somatropin.

D) Hypertension: Not a typical adverse effect of somatropin.

In which patient population is somatropin commonly indicated for use?

A) Patients with closed epiphyses

B) Patients with acute critical illness

C) Patients with Prader-Willi syndrome

D) Patients with severe non-proliferative diabetes retinopathy

Answer: C) Patients with Prader-Willi syndrome

Rationale:

Somatropin is indicated for growth failure associated with conditions like Prader-Willi syndrome.

Closed epiphyses, acute critical illness, and severe non-proliferative diabetes retinopathy are contraindications for somatropin use.

Incorrect Options:

A) Patients with closed epiphyses: Contraindicated for somatropin use.

B) Patients with acute critical illness: Contraindicated for somatropin use.

D) Patients with severe non-proliferative diabetes retinopathy: Contraindicated for somatropin use.

What is the primary indication for somatropin use?

A) Reduction of muscle mass

B) Treatment of acute critical illness

C) Management of closed epiphyses

D) Treatment of growth failure associated with Prader-Willi syndrome

Answer: D) Treatment of growth failure associated with Prader-Willi syndrome

Rationale:

Somatropin is indicated for the treatment of growth failure associated with conditions like Prader-Willi syndrome.

Reduction of muscle mass, treatment of acute critical illness, and management of closed epiphyses are not primary indications for somatropin.

Incorrect Options:

A) Reduction of muscle mass: Not a primary indication for somatropin.

B) Treatment of acute critical illness: Contraindicated for somatropin use.

C) Management of closed epiphyses: Contraindicated for somatropin use.

What is the primary pathophysiological mechanism of diabetes insipidus?

A) Hyposecretion of antidiuretic hormone (ADH)

B) Hypersecretion of ADH

C) Increased water permeability of renal tubules

D) Decreased plasma osmolality

Answer: A) Hyposecretion of antidiuretic hormone (ADH)

Rationale:

Diabetes insipidus is characterized by a decrease in ADH secretion, leading to the inability to concentrate urine and excessive water loss through polyuria.

Hypersecretion of ADH is characteristic of syndrome of inappropriate antidiuretic hormone (SIADH).

Increased water permeability of renal tubules is a pharmacodynamic action of desmopressin (DDAVP).

Decreased plasma osmolality is not a characteristic feature of diabetes insipidus.

Incorrect Options:

B) Hypersecretion of ADH: Characteristic of SIADH, not diabetes insipidus.

C) Increased water permeability of renal tubules: Desmopressin (DDAVP) action, not a pathophysiological mechanism of diabetes insipidus.

D) Decreased plasma osmolality: Not a characteristic feature of diabetes insipidus.

Which medication is commonly used to treat neurogenic diabetes insipidus?

A) Furosemide

B) Desmopressin acetate (DDAVP)

C) Hydrochlorothiazide

D) Spironolactone

Answer: B) Desmopressin acetate (DDAVP)

Rationale:

Desmopressin acetate (DDAVP) is a synthetic form of ADH commonly used to treat neurogenic diabetes insipidus by increasing water permeability and reducing urine volume.

Furosemide, hydrochlorothiazide, and spironolactone are diuretics used for different conditions and are not indicated for diabetes insipidus.

Incorrect Options:

A) Furosemide: Loop diuretic used to treat edema and hypertension.

C) Hydrochlorothiazide: Thiazide diuretic used to treat hypertension and edema.

D) Spironolactone: Potassium-sparing diuretic used to treat heart failure and hypertension.

What is the primary pharmacodynamic action of desmopressin acetate (DDAVP) in the treatment of diabetes insipidus?

A) Decreasing cyclic adenophosine monophosphate (cAMP)

B) Decreasing water permeability

C) Increasing urine volume

D) Increasing water permeability

Answer: D) Increasing water permeability

Rationale:

Desmopressin acetate (DDAVP) increases water permeability of renal tubules by stimulating the V2 receptors, leading to decreased urine volume.

Decreasing cAMP, decreasing water permeability, and increasing urine volume are contrary to the pharmacodynamic action of desmopressin.

Incorrect Options:

A) Decreasing cyclic adenophosine monophosphate (cAMP): Desmopressin increases cAMP levels.

B) Decreasing water permeability: Contrary to the pharmacodynamic action of desmopressin.

C) Increasing urine volume: Contrary to the pharmacodynamic action of desmopressin.

What is a potential adverse effect of desmopressin acetate (DDAVP) administration?

A) Hypernatremia

B) Hypoglycemia

C) Erythema and swelling at the injection site

D) Hypertension

Answer: C) Erythema and swelling at the injection site

Rationale:

Erythema and swelling at the injection site are common adverse effects of desmopressin acetate (DDAVP) administration, particularly with intranasal use.

Hypernatremia, hypoglycemia, and hypertension are not typical adverse effects of desmopressin.

Incorrect Options:

A) Hypernatremia: Desmopressin can cause hyponatremia but not hypernatremia.

B) Hypoglycemia: Desmopressin can cause water intoxication leading to dilutional hyponatremia, not hypoglycemia.

D) Hypertension: Not a typical adverse effect of desmopressin.

Which condition is characterized by decreased urine specific gravity and increased serum osmolality?

A) Syndrome of inappropriate antidiuretic hormone (SIADH)

B) Diabetes mellitus

C) Diabetes insipidus

D) Hypothyroidism

Answer: C) Diabetes insipidus

Rationale:

Diabetes insipidus is characterized by decreased urine specific gravity (low urine concentration) and increased serum osmolality due to the inability to concentrate urine.

SIADH is characterized by increased urine concentration and decreased serum osmolality.

Diabetes mellitus and hypothyroidism have different characteristic laboratory findings.

Incorrect Options:

A) Syndrome of inappropriate antidiuretic hormone (SIADH): Characterized by increased urine concentration and decreased serum osmolality.

B) Diabetes mellitus: Characterized by hyperglycemia and glucosuria, not changes in urine specific gravity and serum osmolality.

D) Hypothyroidism: Characterized by decreased metabolic rate and changes in thyroid function tests, not changes in urine specific gravity and serum osmolality.

Which condition is characterized by the suppression of renin and aldosterone due to the overproduction of antidiuretic hormone (ADH)?

A) Syndrome of inappropriate antidiuretic hormone (SIADH)

B) Precocious puberty

C) Diabetes insipidus

D) Hypothyroidism

Answer: A) Syndrome of inappropriate antidiuretic hormone (SIADH)

Rationale:

SIADH is characterized by excessive production of ADH, leading to increased renal water retention and subsequent water intoxication.

This excessive water retention results in hyponatremia and hypo-osmolarity, along with the suppression of renin and aldosterone.

Precocious puberty, diabetes insipidus, and hypothyroidism do not involve the same pathophysiological mechanism.

Incorrect Options:

B) Precocious puberty: Characterized by early development of secondary sexual characteristics.

C) Diabetes insipidus: Characterized by decreased ADH secretion and inability to concentrate urine.

D) Hypothyroidism: Characterized by decreased thyroid hormone production and metabolic rate.

Which malignancy is commonly associated with an increased incidence of Syndrome of Inappropriate Antidiuretic Hormone (SIADH)?

A) Breast cancer

B) Prostate cancer

C) Lung cancer

D) Colon cancer

Answer: C) Lung cancer

Rationale:

Syndrome of inappropriate antidiuretic hormone (SIADH) commonly occurs in the presence of malignant tumors, with lung cancer being one of the most frequently associated malignancies.

Lung cancers, leukemia, lymphomas, and Hodgkin’s disease are commonly associated with SIADH due to the ectopic production of ADH by tumor cells.

Breast cancer, prostate cancer, and colon cancer are not typically associated with SIADH.

Incorrect Options:

A) Breast cancer: Not commonly associated with SIADH.

B) Prostate cancer: Not commonly associated with SIADH.

D) Colon cancer: Not commonly associated with SIADH.

Which hormone agonist is commonly used in the treatment of central precocious puberty?

A) Leuprolide acetate (Lupron)

B) Growth hormone (GH)

C) Insulin-like growth factor 1 (IGF-1)

D) Thyroid hormone

Answer: A) Leuprolide acetate (Lupron)

Rationale:

Leuprolide acetate (Lupron) is a luteinizing hormone (LH)-releasing hormone agonist commonly used in the treatment of central precocious puberty.

It suppresses the production of ovarian and testicular steroids, thereby delaying the onset of puberty.

GH, IGF-1, and thyroid hormone are not indicated for the treatment of precocious puberty.

Incorrect Options:

B) Growth hormone (GH): Not indicated for the treatment of precocious puberty.

C) Insulin-like growth factor 1 (IGF-1): Not indicated for the treatment of precocious puberty.

D) Thyroid hormone: Not indicated for the treatment of precocious puberty.

What is a potential adverse effect of Leuprolide acetate (Lupron) administration?

A) Hyperglycemia

B) Hypertension

C) Pain at the injection site

D) Hypernatremia

Answer: C) Pain at the injection site

Rationale:

Pain at the injection site is a common adverse effect of Leuprolide acetate (Lupron) administration.

It is important for healthcare providers to monitor for and manage injection site reactions.

Hyperglycemia, hypertension, and hypernatremia are not typically associated with Leuprolide acetate (Lupron) use.

Incorrect Options:

A) Hyperglycemia: Not typically associated with Leuprolide acetate (Lupron) use.

B) Hypertension: Not typically associated with Leuprolide acetate (Lupron) use.

D) Hypernatremia: Not typically associated with Leuprolide acetate (Lupron) use.

Until what age is Leuprolide acetate (Lupron) commonly administered in the treatment of central precocious puberty?

A) Age 10 in girls and age 11 in boys

B) Age 11 in girls and age 12 in boys

C) Age 12 in girls and age 13 in boys

D) Age 13 in girls and age 14 in boys

Answer: B) Age 11 in girls and age 12 in boys

Rationale:

Leuprolide acetate (Lupron) is commonly administered until age 11 in girls and age 12 in boys for the treatment of central precocious puberty.

It is important to monitor the progression of puberty and adjust treatment duration accordingly.

The other age ranges are not typical durations for Leuprolide acetate (Lupron) administration in central precocious puberty.

Incorrect Options:

A) Age 10 in girls and age 11 in boys: Incorrect age range for Leuprolide acetate (Lupron) administration.

C) Age 12 in girls and age 13 in boys: Incorrect age range for Leuprolide acetate (Lupron) administration.

D) Age 13 in girls and age 14 in boys: Incorrect age range for Leuprolide acetate (Lupron) administration.