WBR0414: Difference between revisions

Jump to navigation Jump to search
No edit summary
YazanDaaboul (talk | contribs)
No edit summary
Line 1: Line 1:
{{WBRQuestion
{{WBRQuestion
|QuestionAuthor={{Rim}}, {{AJL}} {{Alison}}
|QuestionAuthor={{YD}} (Reviewed by {{YD}})
|ExamType=USMLE Step 1
|ExamType=USMLE Step 1
|MainCategory=Pharmacology
|MainCategory=Pharmacology
Line 8: Line 8:
|MainCategory=Pharmacology
|MainCategory=Pharmacology
|SubCategory=Renal
|SubCategory=Renal
|MainCategory=Pharmacology
|MainCategory=Pharmacology
|MainCategory=Pharmacology
|MainCategory=Pharmacology
|MainCategory=Pharmacology
Line 20: Line 21:
|MainCategory=Pharmacology
|MainCategory=Pharmacology
|SubCategory=Renal
|SubCategory=Renal
|Prompt=A 76-year-old male, recently diagnosed with heart failure, presents to the physician’s office with complaints of dyspnea upon rest and fatigue. Physical examination reveals jugular venous distension and bilateral lower extremity pitting edema. Pulmonary auscultation reveals crackles at the base of lungs bilaterally. The physician prescribes a diuretic to relieve his symptoms. Several weeks later, the patient’s routine work-up reveals elevated serum calcium and uric acid levels. Based on the image below, the diuretic prescribed to this patient acts at the level of which segment of the nephron?
|Prompt=A 76-year-old man presents to the physician’s office with complaints of dyspnea at rest and fatigue for the past 2 weeks. The patient has been recently diagnosed with congestive heart failure. Physical examination in the office is remarkable for jugular venous distension and bilateral lower extremity pitting edema. Pulmonary auscultation is significant for crackles at the lung bases bilaterally. The physician prescribes a diuretic to relieve the patient's symptoms. Several weeks later, the patient’s routine work-up demonstrates elevated concentrations of serum calcium and uric acid. Based on the image below, the diuretic prescribed to this patient acts at the level of which segment of the nephron?


[[Image:Nephron.jpg|400px]]
[[Image:Nephron.jpg|400px]]
|Explanation=[[Thiazide diuretics]] inhibit NaCl reabsorption at the distal tubule level. [[Thiazide]]s are commonly prescribed for patients with heart failure. Frequent side effects are often summarized with the mnemonic hyperGLUC: hyperGlycemia, hyperLipidemia, hyperUricemia, and hyperCalcemia. 
|Explanation=[[Thiazide diuretics]] inhibit NaCl reabsorption at the level of the distal tubule. [[Thiazide]]s are commonly prescribed to patients with advanced heart failure for relief of symptoms associated with fluid overload. The most common adverse drug reactions associated with thiazide intake are hyperglycemia, hyperlipidemia, hyperuricemia, and hypercalcemia.
 
|EducationalObjectives=
Thiazide diuretics inhibit NaCl reabsorption by inhibiting the NaCl channel in the distal tubule. They are commonly prescribed for patients with heart failure.  Common side effects include hyperGLUC: hyperGlycemia, hyperLipidemia, hyperUricemia, and hyperCalcemia.
|References=First Aid 2014 page 425
 
|AnswerA=A
|AnswerA=A
|AnswerAExp=The proximal tubule is the action site of [[osmotic diuretics]] such as [[mannitol]] and [[carbonic anhydrase inhibitors]], including [[acetazolamide]].
|AnswerAExp=The proximal convoluted tubule is the site of action of osmotic diuretics, such as mannitol, and carbonic anhydrase inhibitors.
|AnswerB=B
|AnswerB=B
|AnswerBExp=The thin descending [[loop of Henle]] is not the site of action of any diuretic.
|AnswerBExp=The thin descending [[loop of Henle]] is not a specific site of action of any diuretic.
|AnswerC=C
|AnswerC=C
|AnswerCExp=Thick ascending [[loop of Henle]] is the action site of loop diuretics.
|AnswerCExp=Thick ascending loop of Henle is the site of action of loop diuretics.
|AnswerD=D
|AnswerD=D
|AnswerDExp=[[Thiazide diuretics]] inhibit NaCl reabsorption at the level of the distal tubule.  Side effects of [[thiazide diuretics]] include hypercalcemia and hyperuricemia.
|AnswerDExp=[[Thiazide]] diuretics inhibit NaCl reabsorption at the level of the distal tubule.
|AnswerE=E
|AnswerE=E
|AnswerEExp=The collecting duct is the main site of action of [[aldosterone receptor antagonists]], such as [[spironolactone]].
|AnswerEExp=The collecting duct is the main site of action of [[aldosterone receptor antagonists]], such as [[spironolactone]].
|EducationalObjectives=[[Thiazide diuretics]] inhibit NaCl reabsorption at the level of the distal tubule.
|References=First Aid 2014 page 425
|RightAnswer=D
|RightAnswer=D
|WBRKeyword=loop of henle, action site, kidney, cardiology, excratory system, thiazide diuretics,  
|WBRKeyword=Thiazide, Nephron, NaCl channel, Congestive heart failure, Fluid overload, Pharmacologic therapy, Hypercalcemia, Hyperuricemia
|Approved=Yes
|Approved=Yes
}}
}}

Revision as of 22:34, 17 February 2015

 
Author [[PageAuthor::Yazan Daaboul, M.D. (Reviewed by Yazan Daaboul, M.D.)]]
Exam Type ExamType::USMLE Step 1
Main Category MainCategory::Pharmacology
Sub Category SubCategory::Renal
Prompt [[Prompt::A 76-year-old man presents to the physician’s office with complaints of dyspnea at rest and fatigue for the past 2 weeks. The patient has been recently diagnosed with congestive heart failure. Physical examination in the office is remarkable for jugular venous distension and bilateral lower extremity pitting edema. Pulmonary auscultation is significant for crackles at the lung bases bilaterally. The physician prescribes a diuretic to relieve the patient's symptoms. Several weeks later, the patient’s routine work-up demonstrates elevated concentrations of serum calcium and uric acid. Based on the image below, the diuretic prescribed to this patient acts at the level of which segment of the nephron?

]]

Answer A AnswerA::A
Answer A Explanation AnswerAExp::The proximal convoluted tubule is the site of action of osmotic diuretics, such as mannitol, and carbonic anhydrase inhibitors.
Answer B AnswerB::B
Answer B Explanation [[AnswerBExp::The thin descending loop of Henle is not a specific site of action of any diuretic.]]
Answer C AnswerC::C
Answer C Explanation AnswerCExp::Thick ascending loop of Henle is the site of action of loop diuretics.
Answer D AnswerD::D
Answer D Explanation [[AnswerDExp::Thiazide diuretics inhibit NaCl reabsorption at the level of the distal tubule.]]
Answer E AnswerE::E
Answer E Explanation [[AnswerEExp::The collecting duct is the main site of action of aldosterone receptor antagonists, such as spironolactone.]]
Right Answer RightAnswer::D
Explanation [[Explanation::Thiazide diuretics inhibit NaCl reabsorption at the level of the distal tubule. Thiazides are commonly prescribed to patients with advanced heart failure for relief of symptoms associated with fluid overload. The most common adverse drug reactions associated with thiazide intake are hyperglycemia, hyperlipidemia, hyperuricemia, and hypercalcemia.

Educational Objective: Thiazide diuretics inhibit NaCl reabsorption at the level of the distal tubule.
References: First Aid 2014 page 425]]

Approved Approved::Yes
Keyword WBRKeyword::Thiazide, WBRKeyword::Nephron, WBRKeyword::NaCl channel, WBRKeyword::Congestive heart failure, WBRKeyword::Fluid overload, WBRKeyword::Pharmacologic therapy, WBRKeyword::Hypercalcemia, WBRKeyword::Hyperuricemia
Linked Question Linked::
Order in Linked Questions LinkedOrder::