WBR244

Author	[[PageAuthor::Gerald Chi (Reviewed by Yazan Daaboul, M.D.)]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Pharmacology
Sub Category	SubCategory::Vascular
Prompt	[[Prompt::A 24-year-old woman presents to her primary care physician with complains of finger discoloration and tingling sensations of her digits. She states that her fingers turn blue upon brief exposure to cold water, and 10 minutes later, the fingers appear pale and eventually become red and swollen. When her fingers are warmed up, their color returns to normal and the swelling disappears. She recalls that during winter time last year, she had similar complaints, and she had an ulcer on her left index finger that eventually healed. Upon further questioning, the patient denies fevers, recent weight changes, fatigue, skin changes, dysphagia, or joint pains or deformities. Which of the following pharmacologic agents is effective to manage this patient's condition?]]
Answer A	AnswerA::Nifedipine
Answer A Explanation	AnswerAExp::Nifedipine is a dihydropyridine calcium channel blocker that is effective in the management of Raynaud's phenomenon.
Answer B	AnswerB::Ramipril
Answer B Explanation	AnswerBExp::ACE-inhibitors are not effective in the management of Raynaud's phenomenon.
Answer C	AnswerC::Diltiazem
Answer C Explanation	AnswerCExp::Non-dihydropyridine calcium channel blockers are not effective in the management of Raynaud's phenomenon.
Answer D	AnswerD::Verapamil
Answer D Explanation	AnswerDExp::Non-dihydropyridine calcium channel blockers are not effective in the management of Raynaud's phenomenon.
Answer E	AnswerE::Metoprolol
Answer E Explanation	AnswerEExp::Beta-blockers are not effective in the management of Raynaud's phenomenon.
Right Answer	RightAnswer::A
Explanation	[[Explanation::Raynaud's phenomenon is characterized by transient digital ischemia due to excessive vasoconstriction triggered by either cold temperatures or stressful situations. Clinical manifestations of Raynaud's phenomenon often include vasoconstrictive changes (well-demarcated areas of pallor or bluish (cyanotic) discoloration of the digits) followed by vasodilatory changes and reactive hyperemia (red skin). Raynaud's phenomenon may either be an isolated phenomenon (primary) or a manifestation of more serious, systemic diseases (secondary), such as CREST syndrome. Raynaud's phenomenon is typically managed by avoiding triggers, such as keeping warm hands during winter seasons, and possibly vasodilators. The addition of pharmacologic agents may be reserved to patients to experience severe vasoconstrictive changes, such as those who develop digital ulcers. Dihydropyridine calcium channel blockers (CCBs), such as nifedipine, amlodipine, or felodipine, are the first-line pharmacologic agents for Raynaud's phenomenon. Other pharmacologic agents include nitroglycerin, hydralazine, papaverine, minoxidil, prostaglandins, or niacin, all of which have not been as extensively studied as CCBs for the management of Raynaud's phenomenon. Triphasic discoloration of digits on exposure to cold environment is a typical presentation for Raynaud phenomenon. Among the drug classes that have been used are calcium channel blockers, vasodilators, sympatholytic agents, and prostaglandins Educational Objective: Raynaud's phenomenon is typically managed by avoiding triggers, such as keeping warm hands during winter seasons, and possibly vasodilators. The addition of pharmacologic agents may be reserved to patients to experience severe vasoconstrictive changes, such as those who develop digital ulcers. Dihydropyridine calcium channel blockers (CCBs), such as nifedipine, amlodipine, or felodipine, are the first-line pharmacologic agents for Raynaud's phenomenon. References: Wigley FM. Raynaud's phenomenon. N Engl J Med. 2002;347:1001-8. First Aid 2015 page 301.]]
Approved	Approved::No
Keyword	WBRKeyword::Raynaud's phenomenon, WBRKeyword::Calcium channel blockers, WBRKeyword::Digital ischemia, WBRKeyword::Pharmacologic therapy
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::