Immuno q

[MudPhud20XX]

From UW....

A 52 yr old woman comes to the emergency dept with pain and redness affecting her lt. leg. The pt's symptoms began 2 days ago and have progressed to the point where she cannot walk w/o experiencing severe pain. Physical exam shows a large, erythematous area with indistinct margins over her lt. leg. The area feels hot and indurated and is exquisitely tender. She is admitted to the hospital for severe lt. leg cellulitis and is started on iv cevazolin. Several minutes after the infusion is started, she experiences shortness of breath, diffuse itching, and dizziness. Her bp is 64/38 and HR is 130. On exam, there is a diffuse erythematous skin rash and bilateral wheezing is heard on lung auscultion.

Which of the following is most likely to be elevated in this pt's serum as a result of her medication reaction?

A. 5-hydroxyindoleacetic acid
B. alkaline phosphatase
C. calcitonin
D. myeloperoxidase
E. tryptase

---

Members don't see this ad.

 

[TheNsg300]

I wud have to go wit E,,tryptase is one of the enzymes released by mast cells/basophils in Type I HSR,,as in this case of anaphylactic shock,,

 

[MudPhud20XX]

I wud have to go wit E,,tryptase is one of the enzymes released by mast cells/basophils in Type I HSR,,as in this case of anaphylactic shock,,

where the heck did you learn about tryptase???

 

[TheNsg300]

Man,,i'm sure u would find it in several texts,,I think it was on becker's immuno I read it.

 

[Phloston]

From UW....

A 52 yr old woman comes to the emergency dept with pain and redness affecting her lt. leg. The pt's symptoms began 2 days ago and have progressed to the point where she cannot walk w/o experiencing severe pain. Physical exam shows a large, erythematous area with indistinct margins over her lt. leg. The area feels hot and indurated and is exquisitely tender. She is admitted to the hospital for severe lt. leg cellulitis and is started on iv cevazolin. Several minutes after the infusion is started, she experiences shortness of breath, diffuse itching, and dizziness. Her bp is 64/38 and HR is 130. On exam, there is a diffuse erythematous skin rash and bilateral wheezing is heard on lung auscultion.

Which of the following is most likely to be elevated in this pt's serum as a result of her medication reaction?

A. 5-hydroxyindoleacetic acid
B. alkaline phosphatase
C. calcitonin
D. myeloperoxidase
E. tryptase

It's tryptase. It's arguably elevated in anaphylaxis but isn't done clinically because 1) the Dx of anaphylaxis is clinical and based on Hx, 2) it's not very reliable, and 3) it won't change management because one would Tx the anaphylaxis anyway. One could argue for a tryptase for curiosity sake to avoid a particular allergen in the future, but once again, it's not reliable and one could always do a skin test if he or she cared enough and wasn't confident in his or her clinical Dx.

 

[Transposony]

AFAIK tryptase is specific to mast cells and serves as a marker of mast cell activation.