View source for WBR0180

{{WBRQuestion
|QuestionAuthor=Mugilan Poongkunran
|ExamType=USMLE Step 3
|MainCategory=Primary Care Office
|SubCategory=Allery/Immunology
|Prompt=A 23 year old female comes to your office with 6 month H/O cold intolerance.  She says that when the weather is cold, her fingers get numb and turn blue.  She wears gloves to keep her hand warm, but it does not always work.  She does not smoke or consume alcohol or use any illicit drugs.  She is sexually active and use condoms as contraception.  She is an accountant and says that her work is very stressful.  Physical examinations are well within normal limits.  What is the best next step in her line of management?
A.	Cold water challenge test
B.	Nailfold capillaroscopy
C.	Topical nitroglycerine
D.	Nifedipine
E.	Prazosin
|Explanation=The [[Raynaud's phenomenon]] (RP) is an exaggerated vascular response to cold temperature or emotional stress.  The phenomenon is manifested clinically by sharply demarcated color changes of the skin of the digits.  Abnormal vasoconstriction of digital arteries and cutaneous arterioles due to a local defect in normal vascular responses is thought to underlie the disorder.  A diagnosis of Raynaud's phenomenon may be made if the patient provides a history of the sudden onset of symptoms characteristic of a Raynaud attack.  We initiate pharmacotherapy in patients in whom general non-pharmacologic treatment measures alone are insufficient.  Calcium channel blockers are the first line drugs for both primary and secondary Raynaud's phenomenon.
|AnswerA=Incorrect
|AnswerAExp=A cold water challenge test can induce an attack of Raynaud's phenomenon.  It is not recommended since the responses are inconsistent even in those with definite Raynaud's phenomenon.  Since it does not consistently trigger an attack, history itself is considered diagnostic.
|AnswerB=Incorrect
|AnswerBExp=Nailfold capillaroscopy, videomicroscopy, thermography, angiography, laser Doppler imaging, and direct measures of skin temperature and local blood flow are other diagnostic tools used to assess the vascular responses in the digits and skin.  History itself is considered diagnostic since no simple office test consistently triggers an attack.
|AnswerC=Incorrect
|AnswerCExp=Nitroglycerine is not a first line drug for this condition and it is usually used as adjunct to calcium channel blockers for treatment of severe cases.
|AnswerD=Correct
|AnswerDExp=Slow-release or long-acting preparations of the calcium channel blockers (CCBs), such as nifedipine or amlodipine, are the first line drugs in the non-urgent management of Raynaud's phenomenon that has not responded adequately to general measures.
|AnswerE=Incorrect
|AnswerEExp=Prazosin, an alpha channel blocker is effective, however patients eventually become refractory to it.
|RightAnswer=D
|Approved=Yes
}}