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Author7 Posts
  #1

A 58-year-old woman had a mitral valve replacement, and was placed on
anticoagulants and prophylactic antibiotics following her surgery. Five
days after her surgery, she developed a sharply demarcated, erythematous
rash on her left thigh . Two days after the rash appeared, large
hemorrhagic bullae began to form in the area of the rash. Which of
the following medications most likely caused the patient's rash?
A. Aspirin
B. Cefazolin
C. Heparin
D. Vancomycin
E. Warfarin

  #2

my partially "ejumacated" guess is cefazolin (urticarial lesion) {any of those may cause a rash.}

heparin& coumadin -hemmmorhage, vanco- more generalized -red man syndrome, heparin also thrombocytopenia.


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Smell the coffee! "Is That an Osler move??"

  #3

it should be warfarin.... causing rash between 3-10 day of treatment, which may progress to haemoorhagic bullae and necrosis.... all this due to depletion of protein C.

cefazolin can cause rash if pt is allergic, there wont be any haem bullae

Heparin can cause thrombocytopenia but not skin necrosis

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  #4

B. Cefazolin

___________________
Courage does not always ROAR. Sometimes courage is the quiet voice at the end of the day saying, "I will try again tomorrow" - Mary Anne Radmacher

  #5

also must be concerned with 15-20% cross reactivity of cephalosporins with pennicillins reactions

___________________
Smell the coffee! "Is That an Osler move??"

  #6

Roopashri is right...

E. Warfarin is a coumarin anticoagulant used for the prophylaxis and treatment of thromboembolic complications associated with cardiac valve replacement and atrial fibrillation, as well as the prophylaxis and treatment of venous thrombosis and pulmonary embolism. Warfarin may cause necrosis of the skin (typically on the breasts, thighs, and buttocks) generally between the third and tenth days of therapy. The lesions are initially sharply demarcated, erythematous, and purpuric. They may resolve or progress to large, irregular, hemorrhagic bullae that can eventually lead to necrosis. The mechanism for this reaction is related to warfarin's ability to deplete protein C, which can lead to a state of hypercoagulability and thrombosis in the cutaneous microvasculature.
Aspirin (choice A) is commonly used for its antiplatelet effect; however, it would not be indicated for anticoagulation of a patient with a recent cardiac valve replacement. Furthermore, aspirin is not associated with the development of this type of skin necrosis.
Cefazolin (choice B) is a first-generation cephalosporin antibiotic commonly used as a perioperative prophylactic agent. If the patient was allergic to this antibiotic, an erythematous rash might have appeared. However, the rash would not lead to the appearance of large, hemorrhagic bullae.
Heparin (choice C) is an intravenous anticoagulant indicated for the prophylaxis and treatment of thromboembolic complications associated with cardiac valve replacement and atrial fibrillation. It is also indicated for the prophylaxis and treatment of venous thrombosis, pulmonary embolism, and for treatment of some coagulopathies. Although heparin is associated with the development of thrombocytopenia, it is not associated with skin necrosis.
Vancomycin (choice D) is an antibiotic typically reserved for treatment of life-threatening infections caused by gram-positive organisms. If vancomycin is administered too rapidly via the intravenous route, a maculopapular rash may appear on the chest and on the extremities. However, once the administration is complete, the rash usually disappears in a few hours.



  #7

wow good ques










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