Pharmacology of Renal System and Diuretics: MCQ

Pharmacology of Renal System and Diuretics

Multiple Choice Question

1) Osmotic diuretics are a class of drugs that work by increasing the osmolarity (concentration) of the filtrate in the renal tubules, which inhibits the reabsorption of water and electrolytes such as sodium and chloride. This results in increased urine output and removal of excess fluid from the body.
Osmotic diuretics are contraindicated in...........................................?

a) Increased intracranial tension
b) Increased intraocular tension
c) Established acute renal failure
d) Poisonings

2) The antidiuretic action of Desmopressin is due to activation of...........................................?

a) V 1a receptor
b) V 2 receptor
c) V 1b receptor
d) V1 and V2 receptor

3)Furosemide is a loop diuretic that acts on the ascending limb of the loop of Henle in the kidney. Furosemide increases the excretion of all of the following except: 

a) Sodium
b) Potassium
c) Uric acid
d) Calcium and magnesium

4) Acute mountain sickness (AMS) is a condition that can occur when individuals ascend to high altitudes (usually above 8,000 feet or 2,400 meters) too quickly, and their bodies are not able to acclimatize to the decreased oxygen levels in the air.

Which of the following drugs would be appropriate for them to take to prevent mountain sickness? 

a) Acetazolamide
b) Furosemide
c) Hydrochlorothiazide
d) Spironolactone

5) Nephrogenic diabetes insipidus (NDI) is a condition in which the kidneys are unable to respond to antidiuretic hormone (ADH), also known as vasopressin. This leads to an inability to concentrate urine and excessive urination, which can cause dehydration, electrolyte imbalances, and other complications.

Drug of choice for nephrogenic diabetes insipidus is: 

a) Lypressin
b) Hydrochlorothiazide
c) Terlipressin
d) Vasopressin

6) Which of the following agent is the most effective in the treatment of hepatic edema? 

a) Chlorthalidone
b) Triamterene
c) Furosemide
d) Spironolactone

7) All of the following drugs are nephrotoxic except 

a) Amphotericin
b) Lithium
c) Metronidazole
d) Statins

8) The symptoms related to the toxicity of loop diuretics is: 

a) Allergic reaction
b) Deafness
c) Hypomagnesemia
d) Hyperuricemia

9) Aminoglycosides induced nephrotoxicity is in the order of

 a) Gentamicin> Tobramycin>Amikacin>Netilmicin> Streptomycin
b) Streptomycin > Tobramycin >Amikacin>Netilmicin > Gentamicin
c) Gentamicin > Amikacin > Netilmicin > Tobramycin > Streptomycin
d) Tobramycin > Amikacin>Netilmicin> Streptomycin > Gentamicin

10) All of the followings are non-renal actions of anti-diuretic hormone except 

a) a neurotransmitter in the central nervous system
b) promotes hemostasis
c) is a potent vasoconstrictor
d) increases the permeability of the membrane to water

11) Which of the following drugs is used for urinary incontinence?
a) Flavoxate
b) Sodium citrate
c) Trimethoprim
d) Phenazopyridine

12) Concurrent use of Spironolactone & ACE inhibitors should be avoided because of the danger of – 

a) Hyperglycemia
b) Hyperkalemia
c) Hypokalemia
d) Hypoglycemia

13) The following diuretic promotes calcium reabsorption: 

a) Spironolactone
b) Furosemide
c) Chlorothiazide
d) None of the above

Amiloride is a medication that belongs to the class of potassium-sparing diuretics. It works by blocking the activity of a specific sodium channel in the kidneys, which helps to reduce the amount of sodium and water that the body retains. Unlike other diuretics, amiloride does not cause potassium loss and may actually increase the levels of potassium in the blood.
14) Following are the uses of Amiloride: 

a) Adjunct to K+ wasting diuretics
b) Lithium induced nephrogenic diabetes insipidus
c) Congestive heart failure
d) a and b
e) a, b and c

15) Which one of the following diuretics is effective in severe renal failure?
a) Loop diuretics
b) K+ sparing diuretics
c) Thiazides
d) Carbonic anhydrase inhibitors

16) Following statements about osmotic diuretics are true, except? 

a) Mannitol gets filtered in the glomerulus, but cannot be reabsorbed
b) To maintain osmotic balance, water is retained in the urine
c) Their presence leads to an increase in the osmolarity of the filtrate
d) All of the above
e) None of the above

17) Which of the following drug and their mechanism of action is not correct? 

a) Acetazolamide: epithelial sodium channel blockers
b) Spironolactone: potassium-sparing diuretics
c) Hydrochlorothiazide: inhibit sodium chloride symporter
d) Bumetanide: inhibits NA+/K+/2Cl- cotransport

18) Based on the V2 receptor, followings are the therapeutic uses of vasopressin, except: 

a) Diabetes insipidus
b) Bedwetting in children
c) Bleeding esophageal varices
d) All of the above

19) Which of the following is a synthetic prodrug of vasopressin? 

a) Lypressin
b)Terlipressin
c) Desmopressin
d) None of the above

20) Long-term use of loop diuretics causes …………………................? 

a) Cirrhosis of liver
b) Deafness
c) Distal nephron hypertrophy
d) Renal insufficiency

Multiple Choice Answers:

1-c) Established acute renal failure

Osmotic diuretics are contraindicated in patients with anuria (the absence of urine formation) or severe renal failure, as these drugs can further reduce renal blood flow and exacerbate renal dysfunction. Additionally, osmotic diuretics should be used with caution in patients with heart failure or pulmonary edema, as they can increase fluid accumulation in the lungs and worsen these conditions. Patients with dehydration, hypernatremia (elevated sodium levels in the blood), or active intracranial bleeding may also be at increased risk for adverse effects from osmotic diuretics and should be monitored closely if these drugs are used. As with all medications, patients should consult their healthcare provider for advice on whether osmotic diuretics are safe and appropriate for their specific medical situation.

2-b) V 2 receptor

The antidiuretic action of desmopressin is due to activation of vasopressin V2 receptors in the renal collecting ducts. Desmopressin is a synthetic analog of vasopressin, a hormone that is normally produced by the hypothalamus and released from the posterior pituitary gland. Vasopressin acts on V2 receptors in the renal collecting ducts to increase the permeability of the cell membranes to water, leading to water reabsorption and a decrease in urine output.

3-c) Uric acid

Furosemide is a loop diuretic that acts on the ascending limb of the loop of Henle in the kidney to inhibit the reabsorption of sodium, chloride, and potassium ions. By blocking the reabsorption of these electrolytes, furosemide increases their excretion in the urine, leading to a reduction in extracellular fluid volume and an increase in urine output. Furosemide can also lead to a decrease in calcium and magnesium levels by increasing its urinary excretion.

4-a) Acetazolamide

Acetazolamide is a carbonic anhydrase inhibitor that helps increase ventilation and decrease the production of cerebrospinal fluid, which can reduce symptoms of AMS. It is usually taken starting a day or two before ascending to high altitude, and continued for a few days after arrival. Acetazolamide can cause side effects such as increased urination, tingling or numbness in the fingers and toes, and changes in taste.

5-b) Hydrochlorothaizide

Nephrogenic diabetes insipidus (NDI) is a condition in which the kidneys are unable to respond to antidiuretic hormone (ADH), also known as vasopressin. This leads to an inability to concentrate urine and excessive urination, which can cause dehydration, electrolyte imbalances, and other complications.
The drug of choice for treating nephrogenic diabetes insipidus is thiazide diuretics, such as hydrochlorothiazide. Thiazide diuretics work by blocking the reabsorption of sodium and chloride in the distal tubules of the kidney, which leads to a decrease in urine output and an increase in urine concentration. Thiazides also have the added benefit of reducing calcium excretion in the urine, which can be useful in patients with hypercalciuria or kidney stones.

 

6-d) Spironolactone & Furosemide

Both spironolactone and furosemide can be used in the treatment of hepatic edema, but the choice of drug may depend on the underlying cause and severity of the edema.
Spironolactone is a potassium-sparing diuretic that works by blocking the effects of aldosterone, a hormone that promotes sodium and water retention. Spironolactone can be effective in the treatment of edema associated with liver cirrhosis, as it can help reduce fluid accumulation and prevent electrolyte imbalances.
Furosemide, on the other hand, is a loop diuretic that works by blocking sodium and chloride reabsorption in the kidneys, leading to increased urine output and decreased fluid accumulation. Furosemide is generally more effective in treating acute hepatic edema, such as that caused by acute liver failure or fulminant hepatitis.

7-c) Metronidazole 

Amphotericin, Lithium, and Metronidazole are all drugs that have been associated with nephrotoxicity, or damage to the kidneys.
Amphotericin is an antifungal medication that can cause nephrotoxicity, particularly at higher doses.
Lithium is a medication commonly used to treat bipolar disorder, but it can also cause nephrotoxicity with long-term use.
Metronidazole is an antibiotic that can cause nephrotoxicity in rare cases, particularly when used in combination with other nephrotoxic drugs.

Statins: These are a class of drugs used to lower cholesterol levels. They are generally considered safe for people with normal kidney function.

8-b) Deafness
The correct answer is (b) Deafness.
Loop diuretics such as furosemide can cause toxicity in some individuals. One of the symptoms related to toxicity is deafness or hearing loss, which can be irreversible. Other symptoms may include electrolyte imbalances such as hypomagnesemia, hypokalemia, and hyperuricemia. Allergic reactions are also possible but are relatively rare. It is important to monitor for signs of toxicity when taking loop diuretics and to report any symptoms to a healthcare provider.

9-a) Gentamicin> Tobramycin>Amikacin>Netilmicin> Streptomycin

Aminoglycosides are a class of antibiotics that can cause nephrotoxicity, which is a type of kidney damage. The severity of nephrotoxicity can vary depending on the specific aminoglycoside used, the dose, and other factors.
Studies have suggested that the order of aminoglycoside-induced nephrotoxicity is Gentamicin > Tobramycin > Amikacin > Netilmicin > Streptomycin. Gentamicin is generally considered the most nephrotoxic of the aminoglycosides, followed by Tobramycin and Amikacin. Netilmicin and Streptomycin are considered to be less nephrotoxic in comparison.

10-d) increases the permeability of the membrane to water 

The correct answer is (d) increases the permeability of the membrane to water.
Anti-diuretic hormone (ADH), also known as vasopressin, is a hormone produced by the hypothalamus and released by the pituitary gland. While its main function is to regulate water balance in the body by increasing water reabsorption in the kidneys, it also has several non-renal actions.
ADH acts as a neurotransmitter in the central nervous system, where it plays a role in social behavior, memory, and learning. It also promotes hemostasis by causing vasoconstriction and increasing platelet aggregation, which can help to prevent bleeding.
In addition, ADH is a potent vasoconstrictor, which can increase blood pressure by constricting blood vessels. This effect is mediated by a specific type of receptor called V1 receptors.

11-a) Flavoxate

Flavoxate is a medication that is used to treat urinary incontinence, which is the involuntary leakage of urine. It works by relaxing the smooth muscles of the bladder and decreasing bladder contractions, which can help to reduce the frequency and urgency of urination.

Sodium citrate is not used for urinary incontinence, but rather for the treatment of urinary tract infections and to relieve symptoms of heartburn and acid reflux.

Trimethoprim is an antibiotic that is used to treat bacterial infections, including urinary tract infections, but it does not have a direct effect on urinary incontinence.

Phenazopyridine is a medication that is used to relieve the pain, burning, and urgency associated with urinary tract infections, but it does not treat urinary incontinence.

12-b) Hyperkalemia

Concurrent use of Spironolactone and ACE inhibitors should be avoided because of the risk of hyperkalemia, which is a condition characterized by high levels of potassium in the blood. Both Spironolactone and ACE inhibitors can increase the level of potassium in the blood, and when used together, the risk of hyperkalemia is even higher.
Spironolactone is a potassium-sparing diuretic that works by blocking the action of aldosterone, a hormone that promotes the retention of sodium and the excretion of potassium in the kidneys. By blocking aldosterone, Spironolactone can cause an increase in the retention of potassium and a decrease in the excretion of sodium in the kidneys, which can lead to hyperkalemia.
ACE inhibitors, on the other hand, work by blocking the activity of an enzyme called angiotensin-converting enzyme (ACE), which is involved in the regulation of blood pressure and fluid balance. By blocking ACE, these medications can cause a decrease in the excretion of potassium in the kidneys, leading to an increase in potassium levels in the blood.

13-d) None of the above

None of the diuretics promote calcium reabsorption. In fact, they have the potential to increase the excretion of calcium in the urine.
Spironolactone is a potassium-sparing diuretic that works by blocking the action of aldosterone in the kidneys. It can lead to an increase in potassium retention and a decrease in sodium and water excretion.
Furosemide is a loop diuretic that inhibits the reabsorption of sodium and chloride in the thick ascending limb of the loop of Henle.
Chlorothiazide is a thiazide diuretic that inhibits the reabsorption of sodium and chloride in the distal convoluted tubule of the nephron. 

14-e) a, b and c

Amiloride is a potassium-sparing diuretic that is used for the following purposes:
a) Adjunct to K+ wasting diuretics: Amiloride is often used in combination with loop or thiazide diuretics to counteract their potassium-wasting effects and prevent hypokalemia.
b) Lithium-induced nephrogenic diabetes insipidus: Amiloride can help to decrease urine output and improve water retention in individuals who experience lithium-induced nephrogenic diabetes insipidus, a condition in which the kidneys are unable to concentrate urine properly.
c) Congestive heart failure: Amiloride can be used as an adjunctive treatment in the management of congestive heart failure, as it can help to reduce fluid accumulation and swelling in the body. 

15-a) Loop diuretics

Loop diuretics are effective in severe renal failure as they work on the ascending limb of the loop of Henle, which is not dependent on glomerular filtration rate. Therefore, option (a) is the correct answer. K+ sparing diuretics and thiazides are less effective in severe renal failure, and carbonic anhydrase inhibitors are not recommended in renal failure due to the risk of acidosis.

16-b)

Osmotic diuretics like mannitol, when administered, increase the osmolarity of the filtrate and urine. They cannot be reabsorbed due to their molecular size and osmotic pressure, leading to an increase in urine output. As they are not reabsorbed, they do not cause water retention in the urine to maintain osmotic balance. Therefore, option (b) is incorrect statement

17-a) Acetazolamide: epithelial sodium channel blockers

Acetazolamide is a carbonic anhydrase inhibitor that works in the proximal convoluted tubule to inhibit the reabsorption of bicarbonate ions, leading to increased excretion of bicarbonate and an alkaline diuresis. It does not block epithelial sodium channels. The other options are correct: (b) Spironolactone is a potassium-sparing diuretic that works by blocking aldosterone receptors in the distal convoluted tubule and collecting duct, leading to increased excretion of sodium and water but decreased excretion of potassium, (c) Hydrochlorothiazide is a thiazide diuretic that inhibits the sodium-chloride symporter in the distal convoluted tubule, leading to increased excretion of sodium, chloride, and water, and (d) Bumetanide is a loop diuretic that inhibits the sodium-potassium-chloride cotransporter in the thick ascending limb of the loop of Henle, leading to increased excretion of sodium, chloride, and water.

18)-d) All of the above

The therapeutic uses of vasopressin are: a) Diabetes insipidus b) Bedwetting in children c) Bleeding esophageal varices. 

19-b) Terlipressin

20-c) Distal nephron hypertrophy
Long-term use of loop diuretics can cause distal nephron hypertrophy. Loop diuretics act on the thick ascending limb of the loop of Henle to inhibit sodium and chloride reabsorption, leading to increased excretion of sodium, chloride, and water. This diuresis can lead to volume depletion and activation of the renin-angiotensin-aldosterone system, which can cause distal nephron hypertrophy over time. This hypertrophy can impair the concentrating ability of the kidney and contribute to renal insufficiency in some cases. Therefore, option (c) is the correct answer.