 Welcome back to our MedSmarter question of the week where we're taking a smarter approach to preparing future physicians. Before we get started, if you'll take just a quick minute and click that like button and also subscribe and turn the bell on so that you'll be notified when we post new videos. Let's get right into that question. As always, we start with the last sentence of the vignette and then go back and read the rest. What diseases are associated with the identification of antimyloperoxidase and antiproteinase-3 antibodies, respectively? Now, you could probably stop here and if you know the answer to these two, immediately go into your question. But let's go ahead and read the vignette and see if it maybe gives us some more information. A 44-year-old man presents to his physician with numbness and tingling on the dorsal surface of his right hand and forearm and raised varicose veins that are firm to the touch along the same distribution. He also complains of weight loss. He has no previous medical history of significance. Lab values show his serum creatine levels of 2.3 mg per deciliter. An immune complex disease is suspected and assays for autoantibodies and neutrophils are conducted. So then what diseases are associated with the antimyloperoxidase and antiproteinase-3 antibodies, respectively? Alright, so this question is pretty straightforward. We could probably answer this question without having any of the vignette other than a straightforward what is antimyloperoxidase and antiproteinase-3 antibodies? What are they associated with? So if you know the answer to this, you can easily rule out some other answer choices. So by looking at these answer choices, we've got quite a few different options for the first antimyloperoxidase. But for the second one, antiproteinase-3 antibodies, there are only two diseases associated with that per this question. So we should be able to rule out two or three answer choices solely by knowing what antiproteinase-3 antibodies are associated with. And if you remember correctly, antiproteinase-3 antibodies are associated with Wagner's granulomatosis. So that tells me that Burger's disease is not a possible answer. Therefore B and D are out. So that narrows down our answer choices to A, C, and E. And we need to be able to recognize the antimyloperoxidase and its association with either temporal arteritis, microscopic polyangitis, or takiasus arteritis. For the most part, this question is going to come down to, do you know this or do you not? So if you know that antimyloperoxidase is associated with microscopic polyangitis because of its P-ANCA association, then therefore you would know that C is the correct answer. And as I said, C is the correct answer because we don't have Burger's disease associated with antiproteinase-3 antibodies. And then our P-ANCA is our perinuclear pattern associated with the nuclear anti-neutrophile cytoplasmic antibody. So that's what the P in P-ANCA stands for. So that is our microscopic polyangitis. The Wegener's granulomatosis here is a vasculitis that we see necrotizing granulomas form in the lung and in the kidneys. And as we've mentioned already, we know that that's a proteinase-3 antibody associated with Wegener's granulomatosis. Wegener's is a cytoplasmic distribution rather than a perinuclear distribution. So Wegener's is a C-ANCA cytoplasmic anti-neutrophil cytoplasmic antibody. And our microscopic polyangitis is a P-ANCA. For both of these, you can do the antibody titer and that will help you be able to indicate disease severity in these particular cases. If you found this material helpful for your studying, please like and consider subscribing to the channel. Also, share this video so that more people can benefit from it like you have.