153 Desquamation, Blistering Disorders & Why Extra Time Might Hurt Your Score

Hello and welcome to the Physician Assistant Exam Review Podcast. This week we’re going to be covering desquamation and vesiculobullous disorders. You can think about how long it took me to say that. Several tries, I’ll tell you that much. Vesiculobullous. It’s really not that hard. This is not just about medical facts here at the Physician Assistant Exam Review Podcast.

It’s about how you think, study, and perform on high-stakes exams. Our motto is think different, work different, score different. This is so important. Each episode we look at medical content like desquamation disorders. We’re going to break them down so you can recognize them on exams and see how to organize them for when you study. We’re also going to show you how to avoid common pitfalls and traps. And we’re going to show you where these are going to show up on your exams.

All of that’s going to work together to make sure you have good retention and better scores. So if you’re working hard, but your scores are not reflecting that work, this is the place for you.

Excellent. All right. So the February cohort, 33 Days to Pass the PANCE, just got kicked off. Yes, February 1st is next Sunday. But we do an onboarding call beforehand to make sure everyone’s up to speed and heading the right direction, which we did last night. And it was fantastic to get to meet everyone and see where everyone is and their enthusiasm and jumping right in and how much fun we’re going to have and how we’re going to be changing lives. Very, very literally.

It’s always very exciting to get these started.

All right. So this week, we’re going to be continuing with dermatology. We’re going to be moving through sections that have always kind of been hard for me and for no good reason other than they’re hard to pronounce. I think that’s really the biggest reason. So give yourself a chance and see if you can’t work through these. So they’re desquamation disorders and then vesiculobullous disorders. Two separate things, but things are definitely going to be asked about on your exam.

Let’s go ahead and get started with our priming questions. Number one, target lesions on the hands and feet after an HSV outbreak suggest what condition? Target lesions on the hands and feet after an HSV outbreak suggest what condition? Fever, mucosal erosions, and less than 10% skin detachment suggest what diagnosis? Fever, mucosal erosions, and less than 10% skin detachment suggest what diagnosis? Severe skin pain, mucosal involvement, and widespread epidermal sloughing suggest what? Life-threatening disorder.

An elderly patient with weeks of pruritus and new tense bullae suggest what? Diagnosis. Painful oral ulcers followed by flaccid blisters that rupture easily suggest what? Autoimmune disease. Painful oral ulcers followed by flaccid blisters that rupture easily suggest what? Autoimmune disease.

All right, I’ll pick those up as we move through. Hopefully those will give you something to be looking for as we go along. So if you are listening to this as you’re out for a walk or a run or you’re driving, it gives you a little something for your subconscious to hang on to as we talk about these things.

Let’s begin by talking about desquamation. This refers to the loss of the outer skin layers due to epidermal cell breakdown. It’s not complicated. Desquamation just means that that outer skin layer breaks off. So the way it’s phrased is that the skin begins to peel or slough off. There can be mild peeling in people who look fine and there can be life-threatening epidermal detachment in critically ill patients. So if you get this over a good portion of your body, obviously you’re going to be in trouble.

Obviously you’re going to have fluid issues. There’s going to be all kinds of problems. So is this a sick person or a not that sick person? What you’re going to be looking for is mucosal involvement, pain, and how much body surface area. That’s how we’re going to determine these. So it’s erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis. That’s what we’re going to be looking for clues to separate.

Usually these follow drug exposure within the past one to three weeks. That’s a key, key trigger. So some sort of new medication that they started. And missing this can be bad because of the high mortality of these diagnoses. So it’s sort of a spectrum. Erythema multiforme is the least severe. Stevens-Johnson syndrome is the intermediate, less than 10% of body surface area affected.

And then toxic epidermal necrolysis is most severe with greater than 30% of body surface area being affected.

So let’s go through these individually and then we’ll wrap it back up all together at the end. Erythema multiforme is an acute immune-mediated hypersensitivity reaction of the skin and perhaps the mucosa. Most commonly triggered by HSV. It also will follow mycoplasma pneumonia. And it represents the mild end of that spectrum we just got done talking about. Clinical presentation here for the skin is going to be, you’re going to get these target lesions. You get an acral distribution, so hands, feet, forearms, and face.

The new vocabulary term for me, I didn’t know that one. You can get, it comes in a symmetric pattern, it’s pretty typical. You don’t really get any mucosal involvement here. And you really don’t get that serious epidermal detachment or significant sloughing. Sloughing? I think it’s sloughing. That’s a better way to say it.

Systemic symptoms are mild or absent. You might get a little bit of a fever. It may follow a herpes infection or mild respiratory illness. The question stem is going to say something like a well-appearing patient with target lesions on the hands and feet after herpes lesions or maybe after atypical pneumonia symptoms, something like that. This is a clinical diagnosis, although you can do HSV PCR or serology. And you might do a medication review, but it’s less necessary than with Stevens-Johnson’s or TEN. Treatments, supportive care, topical corticosteroids, oral antihistamines, that kind of thing.

You can treat the HSV if you want. Discontinue possible triggers if they’re identified. Maybe think about fluids. But most cases will resolve in one to two weeks. This is self-limited and typically does not progress. Stevens-Johnson syndrome, on the other hand, this is a severe mucocutaneous hypersensitivity reaction, usually medication-induced. This would be covering less than 10% of the body surface area with an epidural detachment.

Sorry, not epidural. Epidermal. So skin, right? Epidermal. Sorry, I work in surgery. Epidural is pretty standard for me. Shares a disease spectrum with toxic epidermal necrolysis.

So that’s going to be our spectrum. This is a potentially life-threatening. Our clinical presentation is going to be painful, dusky erythematous or purpuric macules that may coalesce. You’ll get these blisters with progression to epidermal detachment. This will generally involve one or more mucosal surfaces. And here’s an important key. You get a positive Nikolsky sign.

In case you don’t know, this is where you apply pressure laterally to the lesion. And it causes it to shear off. So basically, you just push on it from the side and it comes right off. In this case, you can get a fever, malaise, photophobia, conjunctivitis. The patients will appear ill. And that mucosal surface is going to be painful. The question stem here is going to be a patient started on high-risk meds.

So like a sulfa drug, anticonvulsants, allopurinol, NSAIDs, who develop fever, painful rash, mucosal ulcerations, and early skin sloughing. This is a clinical diagnosis based on mucosal involvement and body surface area. You may want to get some labs because you’re going to want to watch electrolytes here. And if you do a biopsy, it’ll confirm full thickness, epidermal necrosis, and separation if you’re not sure. That’s kind of the definitive test. Treatments. Immediately withdraw the offending medication.

So if they started a medication a week or two ago and they start having these symptoms, step one is stop the medication. They’re going to need to be hospitalized, probably some fluids, electrolytes, pain control. And you may consider the ICU or burn unit for these patients because that sloughing of the skin comes down to reacting like a burn. The next step here is toxic epidermal necrolysis. This is a life-threatening, mucocutaneous hypersensitivity reaction, almost always medication-induced. Here we’re talking about greater than 30% of the body area has epidermal detachment. So there’s that gray zone between 10 and 30, right?

Your exam is not going to ask about that, though, so don’t be too concerned. This involves multiple mucosal surfaces. So oral, ocular, genital. Causing severe pain, dehydration, and high mortality risk. So think Stevens-Johnson, but much, much worse. This requires an ICU stay or a burn unit stay. We have diffuse erythematous or purpuric patches that progress to blistering.

Full thickness epidermal necrosis with sheet-like skin detachment. Pretty gross. Severe mucosal involvement. And again, that positive Nikolsky sign. That’s where that skin is just going to slough right off when you push on those lesions. They have a high fever, profound malaise, and severe skin pain. I mean, makes sense, right?

Again, I like to not try to memorize things, but have a picture make sense. If their skin is sloughing off, if that’s the major concern, the Nikolsky sign makes sense here. Right? That epidermal detachment. If you’re missing 30% of your skin due to a hypersensitivity reaction of some kind, then profound malaise and skin pain kind of makes some sense. Painful swallowing makes sense because you’ve got mucosal involvement. Patients may appear dehydrated.

So your question stem is going to sound something like a middle-aged patient who recently started a new medication with high fever, skin pain, mucosal erosions, and widespread sloughing. The patient may be unable to maintain oral intake and appears acutely ill. That kind of thing is what you’re going to see. This is also a clinical diagnosis based off body surface area involved and mucosal involvement. We’re, again, wanting to do labs to maintain electrolyte balances. Here it’s going to be important to monitor for secondary infections and sepsis because if you have 30% of your epidermis coming off, you are in a bad position for infections. You can do a skin biopsy, again, just like we did before, to show that full thickness, epidermal necrosis, and separation.

Treatment’s going to basically be the same. It’s immediate withdrawal of the offending medication. We’re in the ICU. We have fluids on board. We’re watching for infections. And supportive care.

All right, that closes out desquamation. So to me, the answer is learn those as a group. Don’t learn them separately. They’re basically a spectrum of issues. And the question stem is going to be very much the same. It’s just going to describe someone who’s not sick, someone who’s a little sick, and someone who’s very sick. That’s going to be your separators.

So for erythema multiforme, target lesions, acral distribution, patient looks fine, but they had an HSV infection, and now they have these lesions. Stevens-Johnson, fever and mucosal erosions with less than 10% of the body. They may have a fever. They may be a little ill. They may have a little bit of concerns. Toxic epidermal necrolysis, high fever, skin pain, mucosal erosions, more than 30% of the body affect it. The patient may appear toxic.

Like we’re talking severely sick. They’re in the ICU. So if you’ve got something like minimal or no mucosa, you’re thinking erythema multiforme. If mucosa is involved and they’re sick, it’s going to be either Stevens-Johnson or toxic epidermal necrosis. If they have severe pain, it’s probably going to be toxic epidermal necrosis. Then watch for your body surface area issues. And that’s how you’re going to separate these.

All right, let’s talk about vesiculobullous disorders. It should be easier to say. This is going to be a relatively short episode because I just want to get through these two major topics. Because there are two that I struggled with. So I didn’t want to add much more to this. And I think, again, the reason I struggle with them is because the names are hard to pronounce and hard to think about. So not that the diseases are any harder than anything else, but it’s just in that pronunciation.

So to me, one way to take care of that is to say them out loud. Is to get yourself to be able to say the words. Because you will remember words you can understand, right? If you meet someone and you can’t pronounce their name, you’re not going to remember their name the next time you see them. But if their name is John or Tim, there’s a much higher chance you’re going to remember it because you can pronounce it and you can hold on to it. So I’d recommend just practicing with these. So where does this come from?

Pemphigoid comes from pemphix, which is Greek for blister. And oid just means like, right? So we have a blister-like disorder. These are tense blisters. These will stay intact. So these will have negative Nikolsky signs. This is an autoimmune reaction.

And more common in elderly patients. Clinical presentation. Large, tense bullae on an erythematous base. The blisters don’t rupture easily. Right? So opposite of what we were just talking about. Common on flexor surfaces, abdomen and thighs.

Little to no mucosal involvement. So here’s how you separate this from what we were just talking about. Little or no mucosal involvement. Tense bullae. And the blisters don’t rupture. So do I need to know that they’re on the flexor surfaces? Yeah, that helps.

But if I have the rest of the picture, maybe I don’t need that. It just helps to color it in. In this case, the patient will otherwise be well-appearing. So if they appear well, it’s not Stevens-Johnson. And it’s not toxic epidermal necrosis. The question stem here is going to be an older adult with several weeks of itchy, tense, blisters, and no oral lesions. Something like that.

This will be a clinical diagnosis. And is the Nikolsky sign going to be positive or negative here? Well, it’s going to be negative, right? Because these are tense bullae that don’t rupture. Treatment is going to be high-potency topical corticosteroids. Or systemic steroids. Our goal here is symptom control and prevention of new blisters.

So the key is not only to be able to know how they look different, but also how their treatment is different. We didn’t talk about steroids.

All right, how about pemphigus vulgaris? Pemphigus comes from pemphix, which is blister, referring to the blister-forming disease. These are flaccid blister disorder with fragile bullae that rupture easily. These are prominent mucosal involvement, especially in the mouth. This is an autoimmune reaction. And it can be life-threatening without treatment due to fluid loss and infectious diseases. Sorry, I’m a little distracted with this.

I don’t know where you are. Remember, we’ve got just a ton of snow this last week, right? Like 17, 18 inches. And I can hear kids in the neighborhood running around screaming outside my window. I assume there’s some kind of snowball fight or sledding action going on. I don’t know. I’ve been trying to figure it out for the last little bit.

So sorry if I appear a little distracted.

Let’s keep going. Our skin rash will be flaccid, fragile bullae that break easily. Painful erosions and crusting after bullae rupture. Common on the scalp, face, trunk, and mucosal surfaces. Mucosal involvement is typical. Systemic symptoms. Oral pain and difficulty eating or drinking.

Patients may appear uncomfortable due to painful erosions. The stem here is going to be something like an adult with painful oral ulcers followed by fragile blisters on the skin. This will be a clinical diagnosis, maybe a skin biopsy if you want. Based on our description, do you think the Nikolsky sign will be positive or negative? Here it’s going to be positive. That skin will shear off with lateral pressure. The treatment is going to be systemic corticosteroids are the first line.

And then immunosuppressants. And again, this can be pretty dangerous. So how do you tell these apart? Well, bullous pemphigoid is tense, blisters, elderly patient, minimal or no mucosal involvement, subepidermal split, Nikolsky negative. Pemphigus vulgaris is flaccid, blisters, mucosal involvement. Oral lesions are most common here. Nikolsky positive.

So if it’s tense, think pemphigoid. If it’s flaccid, think pemphigus. So once again, you can see how we just separate these based off of their characteristics. And they’re going to be asked together, right? You’re never going to see these up against pneumonia. You’re never going to see these. Would you see them up against something like chickenpox?

I don’t know, maybe. But you should be able to pull that out pretty easily. The hard part is going to be separating them from each other.

Excellent. All right. As we move through derm, let’s move on to our study tip for today. I have something I wanted to talk about. It’s not exactly a study tip. It’s more of an exam tip for those of you who are struggling. Something I’ve been thinking a lot about over the last, I don’t know, maybe a year or more.

I’ve had more and more students come to me talking about getting extra time on their exams. Talking about getting time and a half or double time. Or if a student fails the exam, they go back to their professors. And their professors are like, oh, you should get extra time. Maybe that’ll help. But they really don’t have an answer or a reason. They just kind of feel like, I don’t know what to do, so let’s get more time.

Because that’ll do something. And I don’t want to talk people out of extra time. Because I don’t think that’s a terrible thing. But I do want you to understand what you’re doing and why you are doing it. Extra time is good if you’re dyslexic and you have trouble reading. Or if you have a vision problem and it takes you longer to get through it. If you have ADD, extra time may be an absolute travesty for you.

From the minute they started describing it to me, I knew for me there’s no chance that I could survive with extra time. And taking a test over two days versus taking it over one day sounds like pure hell to me. Again, everyone’s different. Everyone’s brains work different. I don’t mean to talk you into or out of anything. I just don’t want you to think of it as a magic bullet. Because for some brains, extra time is incredibly helpful.

For other brains, it will make things worse. If you’re prone to talking yourself out of answers, having more time will give you more time to talk yourself out of answers. Within 33 Days to Pass the PANCE, I have some students come to me who struggle on exams and timing and things. And one of the exercises I have them do is to cut their time in half when they practice. So do 60 questions in 30 minutes. And at first they look at me like I’m crazy. But time after time, I have students who come back with higher scores.

Let me say that again. When I have students take their tests with only 30 seconds per question, the majority of them come back with not equivalent scores, but higher scores. This is important to note. Because it’s going to be different for everyone. But I know for me, that extra time would just lead me to talk myself out of things.

Now, here’s what I did come across recently. And I think this is a great idea. If you’ve got ADD and this is a problem for you, and you’re signed up with extra time because you think that’s going to help, what I would recommend, what I would be doing at this point, is I wouldn’t be using that time on questions. I would be using that time on breaks, on closing my eyes, on moving around. So I would still maintain that one minute per question or maybe a little less. But I would throw in there some extra time for me to take a break, extra time to blink, maybe stand up, sit down, that kind of thing. I wouldn’t be using it on the questions because it would only make me crazy to try to spend two minutes per question.

I literally could. Some of you will vehemently disagree with me. But those of you whose brains work the way I do, know that it would be an absolute torture to sit there for longer, to do back-to-back days. But I think that might be a way for an ADD brain to use that time well would be to look into taking some extra mini breaks, I would call them. Maybe you don’t leave the room. Maybe you just stand up and sit down. Maybe you don’t leave the room.

You just put your head down on the table for a second. So consider this. When you’re thinking about your extra time, why are you using it? Why are you getting it? Why are you asking for it? And what are you going to do with it? Because again, I don’t know about you, but I can’t reread questions.

I find it physically painful to go back through and check things. It’s just the way I take tests, just the way that I function. So it’s not that one way is better or worse, but just pay attention to what you do and think about the reasons behind it. Don’t just throw on extra things because they’re available. Use the tools that are available to you if they work for you. But not every tool works in every situation or for every person. I hope that makes sense.

All right, let’s get the answers to our priming questions. Target lesions on the hands and feet after an HSV outbreak suggest what condition? This should be pretty easy now. Erythema multiforme. Fever, mucosal erosions, and less than 10% skin detachment suggest what diagnosis? Stevens-Johnson syndrome. Severe skin pain, mucosal involvement, and widespread epidermal sloughing suggest what?

Life-threatening disorder. I really made these pretty easy now that I’m looking at them. Toxic epidermal necrolysis. An elderly patient with weeks of pruritus and new tense bullae suggests what diagnosis? Bullous pemphigoid. And then painful ulcers, followed by flaccid blisters that rupture easily suggest what? Autoimmune disease, pemphigus vulgaris.

All right, great work today. Dermatology, definitely not in my wheelhouse, not my strong suit. So I appreciate you guys sticking with me as we get through this. Not everything is going to be for everyone. This section, not for me. I feel like I’m saying that more often than not saying it. But regardless, it’s how you break down the material.

It’s how you work your way through it. Especially the stuff that you don’t like. Especially the stuff that you don’t know. That’s going to be 60, 70%, right? For me, I knew I was surgery from day one. There was no question in my mind. So I had to create ways to keep myself interested and keep myself studying and the things I didn’t care that much about.

That’s the hard part. So if this episode helped, here’s the important takeaway. It’s not about memorizing the facts. It’s about knowing what to notice and how to organize it. That’s what we’re talking about and how to think under pressure. Remember, think different, work different, score different. So we train studying.

We train the way you approach questions. We train how you manage yourself during an exam. And your scores go up. If you got a lot out of this, what I would really appreciate is you share the show with friends, with classmates, with faculty. That’s the number one thing you can do for me. The number one thing you can do here. I just got an email today saying someone used the show throughout the didactic year, their clinical year, and for their PANCE.

And they wanted to email me and say how grateful they were for the information here. It’s all here. It’s all free. Please share it with your classmates. Please share it with your faculty. That’s absolutely the number one thing you can do. Anyway, thank you so much.

Take care. And we’ll talk to you again next week. Take care. Take care.