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S2D: The Symptom to Diagnosis Podcast - Episode 24: Rash
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S2D: The Symptom to Diagnosis Podcast - Episode 24: Rash
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Language: EN.
Segment:0 .
[upbeat intro music] [upbeat intro music] [upbeat intro music]
DR. CIFU: I'm Adam Cifu.
DR. STERN: And I'm Scott Stern.
DR. CIFU: And we're here with another episode of S2D, the Symptoms to Diagnosis podcast. This podcast teaches evidence-based strategies for diagnosing common medical symptoms. We begin each episode with a case unknown to one of us, we then discuss five high yield features that help to accurately diagnose the cause of the symptom at hand, we then return to our case before finishing up with a discussion of fingerprints, common misconceptions, pet peeves, and other random pearls of knowledge pertaining to the week's symptom.
DR. CIFU: The cases that we discuss are drawn from our clinical experiences, but because protecting patient privacy is part of our oath, we never discuss actual patients and most cases are composites. So what are we talking about today, Scott?
DR. STERN: Well, I kind of wish we were talking about hyponatremia again, because I know something about that, but today we're talking about rashes.
DR. CIFU: If I have to hear you talk about hyponatremia one more time, I don't know--
DR. STERN: [tern chuckles]
DR. CIFU: Yes, it's rash day. But are we doing it alone today?
DR. STERN: No, no, contrary.
DR. CIFU: No, we're not. We have our very first guest expert, and our expert today is Dr. Sarah Stein. Sarah is a pediatric dermatologist here at the University of Chicago. She's also an associate professor of medicine and pediatrics and a fellow in the Academy of Distinguished Medical Educators. She promises she will not hit us with a pediatrics case today though. So welcome, Dr. Stein.
DR. CIFU: [Dr. Stein] Thank you, Adam and Scott. It's a huge honor, I must admit, a bit intimidating to be a part of your podcast. I listened to the hyponatremia podcast and I was blown away. You both have a very vast depth and breadth of knowledge when you discuss the symptom of the day, so I hope I can adequately contribute.
DR. CIFU: I'm sure you will show us up.
DR. STERN: No doubt.
DR. CIFU: So Sarah, as expert of the day, do you have a case to present to us? [Dr. Stein] Absolutely. Let's hear it. [Dr. Stein] Though, I must say dermatology is such a visual specialty that it's a little disconcerting to not be able to refer to clinical images, but I'll do my best to verbally depict our patient. So Mr. B is a 67-year-old man with a history of diabetes, hypertension, and hypercholesterolemia who presents to the outpatient dermatology office with red welts and blisters worsening for about the past week.
DR. CIFU: He reports his skin feels itchy, but it's not really painful. He tried taking Benadryl, but didn't think that helped. So on exam, he's afebrile and he has normal vital signs. And you're immediately impressed with the rash, which is distributed over his trunk and extremities. He has many discrete and grouped tense blisters with clear to yellow fluid. Underlying many of the blisters, the skin is red and edematous.
DR. CIFU: There are also many of these erythematous, edematous plaques without overlying blisters. The unroofed blister sites look red and moist, and some of them are starting to develop a dry crust from the blister roof. At sites of healed blisters, there are scattered, smooth, pink patches. There's no oral mucosa or genital mucosal involvement and the periocular region, the eyelids, and the conjunctiva appear normal.
DR. CIFU: The patient has minimal scalp hair, but there are no lesions on the scalp, and his palms and soles and nails do not appear to be involved.
DR. CIFU: Great. Boy, we have amazing internal medicine residents here and I have never heard of a description of the skin that was so detailed and perfect. [chuckles] We can see what we're doing wrong. I was also struck by the minimal scalp hair. Is that how you describe me? [Dr. Stein and Dr. Cifu chuckle]
DR. CIFU: Anyway, so let me think about this, I like it, it actually feels a little bit in my wheelhouse, starting with a 67-year-old man with a history of diabetes, hypertension, and hypercholesterolemia, but then it kind of goes off the rails. So we're clearly talking about a patient who's presenting with blisters, and I know that the kind of fancy-schmancy way of talking about this is to talk about the depth of the blisters and the cleavage plane, but I got to say, I don't really know much about that.
DR. CIFU: So when I see blisters, I kind of think of size first, and I think of small blisters with are vesicles and large blisters which are bullae. My next step in thinking about them is usually, are they localized or generalized? Localized for me would be things like maybe an outbreak of HSV, of herpes, or if they're dermatomal, something like obviously zoster, while if they're generalized, I'm going to think of more, obviously, sort of generalized bullous diseases.
DR. CIFU: And then I think probably as an internist, the thing that I worry most about when I see blisters is, is this infectious? Is this something bad? And those might be things that I consider not such bad infections, like zoster herpes, maybe impetigo, if it's a kid, or like bad things like Staph scalded skin, which I guess isn't really an infection, but a reaction to an infection? I don't know.
DR. CIFU: How do you categorize that? [Dr. Stein] Yeah, that is a hematologic dissemination of the toxins, so it's a bloodstream infection, but it's manifesting definitely severely in the skin.
DR. CIFU: TEN, certainly toxic epidermal necrolysis, right? Or Stevens-Johnson, and those people are usually really sick and in horrible pain and I only see that in the hospital when people get admitted with that. And then the non-infectious things, [chuckles] my differential is incredibly short so I hope what is on the differential is one of these cases, but bullous pemphigoid is something that we do occasionally see in older people. Those tend to be tense blisters, which sound kind of like this.
DR. CIFU: And pemphigus vulgaris, I guess, is another thing that we do see. I think that might involve mucous membranes? [Dr. Stein] Yes.
DR. CIFU: Okay, so that sounds less likely in this person. And so going into this I would say, sounds like a not sick person, sounds like generalized blisters, tense blisters. So I'm moving against the infectious etiologies. I'm looking at more what I guess is sort of an autoimmune blistering disease, and I'd kind of pull up at this point with bullous pemphigoid, pemphigus vulgaris and then kind of be stuck, I don't know.
DR. CIFU: [Dr. Stein] So I think you've thought through that in a very organized way and I think that that's key to thinking about rashes. And maybe we should move on here to kind of the five key points when you're thinking about a rash, and then we can return to how we would further the workup in the dermatology office?
DR. CIFU: Sounds good. You really have listened to our podcast.
DR. CIFU: [Cifu and Dr. Stein chuckle]
DR. CIFU: So yeah, take us through the five key points. What's your point one? [Dr. Stein] Well, so the overarching point when thinking through how to diagnose a rash is that morphology, which is really what the appearance of the rash is, will guide your construction of a differential diagnosis. So we'll call point one being that you need to hone in on identifying the primary lesion in order to determine the morphology of the rash.
DR. CIFU: And how do you find the primary lesion? So it sounds like the primary lesion is like what kind of the classic lesion looks like? [Dr. Stein] So I think of the primary lesion as the first element of the rash that arises. And sometimes you actually have to ask the patient, is there an initial lesion here? What was the first thing that you noticed?
DR. CIFU: Okay. [Dr. Stein] And so, that would include things like papules. So is it a small, raised lesion, or is it a larger rough area of skin that's become inflamed? or is it a larger rough area of skin that's become inflamed? So that would be a plaque. Or is it a blister, or as you have mentioned, is it a big fluid-filled bubble or a small one? So a bulla versus a vesicle.
DR. CIFU: Okay. [Dr. Stein] And is it filled with pus which would make it into a pustule or does it have clear fluid? So that would be another primary type of lesion, a papule, vesicle or bulla. We can see blood leaking out into the skin, right? And that can cause petechiae or purpura. And so that's also another type of primary lesion. Cysts, nodules, big masses, tumors, those would be more localized, but primary lesions.
DR. CIFU: Got it. [Dr. Stein] So that's kind of we're thinking about.
DR. STERN: Does it help to ask the patient what came out recently, because as I understand it, these are often going to change over time, the lesions, right? So might it be helpful, if the rash has been there for several weeks, to say point to one that just came out? Would that be useful? [Dr. Stein] Absolutely, yes. So you want to ask what's a fresh lesion, because you really want to think about what it is arising as, and not be misled by all the secondary things that can happen over time.
DR. STERN: Got it.
DR. CIFU: And for you
DR. CIFU: as sort of a pro at this, is the primary lesion usually the most diagnostic for you or is that not always true? [Dr. Stein] Um, yes, I think that it is generally what is most diagnostic.
DR. CIFU: Okay. [Dr. Stein] Yeah. And if we're going to take the next step in terms of a workup of a patient, which is, you know, in dermatology that often involves a skin biopsy, we only want to biopsy a primary lesion, because if we biopsy something later along in the course, we're going to get completely different misleading information.
DR. CIFU: Okay. Okay, so first key point is identify the primary lesion and you did a nice job of sort of describing those. Is it a plaque? Is it a papule? Is it a nodule? Blah, blah, blah. Second key point? [Dr. Stein] So the second key point would be considering what those secondary changes might be and thinking about, because you know how certain things should evolve and so that may additionally help you.
DR. CIFU: So for example, scale would be considered a secondary feature. So is the scale fine and white, or is it yellow and crusty, So is the scale fine and white, or is it yellow and crusty, or is it plate-like and adherent? So that's what you would see in something like psoriasis, right? Those thick plates of scale that stick on, like they describe micaceous, mica, like mica on a rock. Got it.
DR. CIFU: [Dr. Stein] Or is it fine and fluffy? Color can sometimes be considered a secondary characteristic. So is something very red? Is it brown? Is it becoming hyperpigmented or hypopigmented as it ages? And then back to the blistering lesions, what's that fluid like? Is it clear fluid? Is it serous fluid? Is it hemorrhagic fluid or is it purulent?
DR. CIFU: And that can also really kind of help direct you along the course of am I thinking about something infectious or am I thinking about something autoimmune?
DR. CIFU: Cool, so it sounds like the secondary characteristics are not only important because it helps you kind of recognize what the primary lesion was and what's changed, but it's also important because it's helpful diagnostically because some things progress in one way, other things might progress in another way. [Dr. Stein] Absolutely.
DR. CIFU: It's funny I've heard the word micaceous but I never knew it referred to mica, like the little-- [Dr. Stein] Layers on a rock. Yes. That's cool. [Dr. Stein] Yeah.
DR. CIFU: Okay, third key point. Is it, we're going to go to like tertiary lesion at this point since we've done primary and secondary? [all doctors chuckle] [Dr. Stein] Well, so now we use this term reaction pattern, which may be somewhat obscure or confusing to some of the listeners, but I think of this as a pattern of those primary lesions, how they group together or how we can categorize them to think more specifically about a differential diagnosis.
DR. CIFU: So if it's a papular eruption of individual papules, it'll fit into the category of reaction pattern of follicular papular, and that's where we would be thinking about things like acne or folliculitis or rosacea. Whereas if it's a broader, rough, elevated area of skin, a plaque, then we'll think about things in the papulosquamous category, which means they're raised and scaly, and that's where the eczematous disorders, psoriasis, pityriasis rosea, seborrheic dermatitis, those all fit into the papulosquamous category.
DR. CIFU: Scott, do you-- I feel like I never really think about that. Do you think about that at all?
DR. STERN: No, I mean, the terminology is sometimes a barrier for me, but it's certainly helpful as you describe in such detail to get it. I have to admit, if you think about the words, they make sense, but you actually can't just-- If you just spit them out and don't think about the-- Like follicular papular does kind of speaks for itself if you think about follicles, but I often don't have that sophisticated of a look at it.
DR. CIFU: Yeah, it's interesting because I feel like the first two, the primary lesion and the secondary lesion, are things we do and things I imagine the dermatologist's doing because that's like the type one thinking, I recognize that this is what it is. This is actually more and Sarah, you can throw something at me if this seems, I don't know, dismissive - but this feels more like medicine to me where you're like, okay, here's a framework for a differential diagnosis.
DR. CIFU: And so, follicular papular is like pleuritic chest pain while papulosquamous might be non-cardiac chest pain, and each of those have their own differential beneath them. [Dr. Stein] Yeah, I think that that's quite an applicable example. We are often faced with a patient who's red from head to toe and we use the term erythrodermic. And then there's a whole list of things, as soon as you sort of get erythrodermic as the reaction pattern in your mind, you're already thinking about a whole bunch of things that can present with erythroderma, and that kind of gets you started on a way to figure out what's going on with this individual patient.
DR. STERN: I don't know much about erythroderma except I think it's bad. [Dr. Stein] Generally, it's not a good thing.
DR. STERN: That's what I thought.
DR. CIFU: [Cifu And Dr. Stein chuckle]
DR. CIFU: What came to my mind was sunburn. [chuckles]
DR. STERN: What came to my mind is Sézary syndrome. So it just shows.
DR. CIFU: Okay, so we've got first key point, primary lesion, second key point, secondary lesion, third key point is the reaction pattern, and I'm going to think about that as sort of the framework for differential diagnosis. Fourth key point? [Dr. Stein] So the fourth key point gets a little bit more into the details of the individual's eruption and considers shape, configuration, distribution, and global patterns of the rash to give you a little bit more specificity.
DR. CIFU: So shape might refer to individual lesions, so an individual papule could be dome-shaped or it could be kind of sloping. And that can give you kind of two different thoughts on what is going on. You might have annular lesions, which are ring-shaped-
DR. CIFU: Right. [Dr. Stein] -versus discoid which is more coin-shaped. So when it's annular, there's something happening at the rim and not at the center, but if it's discoid or coin-shaped, the same changes are happening over the whole surface of that round circle. Or it could be arcuate, so it's just half a circle, or it could be targetoid, where there are zones of different changes.
DR. CIFU: And all of those things are indicative of different kinds of eruptions.
DR. CIFU: Interesting, so that's sort of as you look closer for whatever sort of lesion, you're just appreciating what the lesion looks like in more depth, because that brings greater specificity, I guess, as you recognize these things. [Dr. Stein] Right, right, so in our case, when I described these urticarial plaques, if I had mentioned that oh, by the way, they're also annular, and some of them are targetoid, that would have already got you thinking about some other entities.
DR. CIFU: Got it.
DR. STERN: It's interesting to me because you use words so well. So like, I would never have thought to describe the lesions as dome-like or cliff-edged yet I can imagine the difference. So when I think about a lipoma, I don't think about cliff-edged, I think about dome-edged. And if I saw a very sharp margin, I would say that doesn't really fit for a lipoma, and yet using these very specific words, you could see how the description would help to be diagnostic and drive someone who doesn't actually know the diagnosis in the right direction.
DR. STERN: [Dr. Stein] Yes, I think that that's something that dermatologists have prided themselves on, is that their descriptive skills are really honed-
DR. STERN: Right. [Dr. Stein] -and that there's a whole vocabulary that's very useful. I must say that now that we're using more and more digital images and they're becoming part of the medical record more and more easily, a lot of that is sort of falling to the wayside, because now when we discuss with our students an eruption, they've already taken a picture and they're looking at the picture now.
DR. STERN: And we're all looking at that and we sort of skip this step of all these words and I don't know how that will impact people's ability to create their differential diagnosis.
DR. STERN: That's interesting.
DR. CIFU: Okay, bring us to the fifth key point. [Dr. Stein] So the fifth key point, absolutely key, is to not forget about the rest of the patient's medical situation. So what other constitutional symptoms do they have? What other medical conditions do they have? What medications are they taking? What have their exposures been? What's their travel history? All of that is supremely important.
DR. CIFU: In dermatology, we do jump to looking at the patient's skin lesions, because the patient can't stop themselves from telling you, "Look, doc, this is what I'm here for." So you can't ignore that, you look at their skin lesion first, but you don't want to forget to then take a history and get all the background information and make sure that you've incorporated that into your thought process.
DR. CIFU: Great. Okay, that is really helpful. Let's go back to the case. So if I think back to where I was [chuckles] pathetically short differential at this time, I think I was talking about bullous pemphigoid or pemphigus vulgaris just because when I think of adults with large blisters, that's sort of what I think about. And I said that at this point, I would probably call the dermatologist. You mentioned a few of the things that you felt were very important in this case, when you kind of described the rash, what else do you think you'd focus on seeing him?
DR. CIFU: [Dr. Stein] Well, so I would sort of summarize the situation as blistering eruption pattern, tense blisters with clear fluid, associated urticarial plaques without mucosal involvement, and a generalized distribution. So that kind of summarizes where we stand.
DR. CIFU: And those urticarial plaques, are those just under the blisters? Or are those even in places- Do you see them everywhere? [Dr. Stein] No, those can be with blisters and without-
DR. CIFU: Okay. [Dr. Stein] And that's sort of key to this diagnosis as well.
DR. CIFU: Okay. [Dr. Stein] And then I would want to be thinking I don't miss infection, right? That's clearly the most urgent thing to assess and rule out and manage, if necessary. So you think maybe like cellulitis can sometimes cause some blistering, but that would be a localized eruption. Impetigo, generally you don't see the intact blisters with impetigo because they're so superficial and they've ruptured.
DR. CIFU: The same would be true for Staph scalded skin syndrome, which would be, you know- Impetigo is usually localized, Staph scalded skin syndrome can be more generalized, but those blisters would be very, very fragile and broken down. Zoster, disseminated varicella, those are going to be vesicles and not big blisters.
DR. CIFU: Got it. [Dr. Stein] And then as you mentioned, Stevens-Johnson TEN, super important not to miss, definitely, you know, patient on multiple medications, you always have to think about that. But again, in this case, no mucosal lesions, the lesions were never described as targetoid, the patient's not ill-appearing.
DR. CIFU: Is impetigo an example of where a secondary lesion would be important? Because if you saw that honey crust that people talk about you'd say, oh- [Dr. Stein] Yes, definitely.
DR. CIFU: -helpful with the diagnosis. [Dr. Stein] That's very helpful, yep.
DR. CIFU: Okay, and so with that, how do you make a diagnosis in this person? Is this a clinical diagnosis? Is this a biopsy diagnosis? [Dr. Stein] So I think we would be very suspicious in this situation of an autoimmune blistering disease, as you mentioned, and because the blisters are tense and there's all of these urticarial plaques, we would definitely be thinking more along the lines of bullous pemphigoid than pemphigus vulgaris, because that's the big difference between those two most common autoimmune blistering diseases, that bullous pemphigoid, the blister plane is deeper, so those blisters are tenser, and the urticarial plaques are very central to the diagnosis, in fact, some patients present only with those before the blisters will start up to weeks to months later.
DR. CIFU: But autoimmune diseases, we definitely want to have a firm diagnosis, and so the next step would be to take biopsies. So we would probably do two biopsies in this situation, one of an actual blister edge that we would send for regular pathology. That way they would be able to tell us exactly where that blister plane is forming and what the inflammation is composed of.
DR. CIFU: And then we would do a second biopsy for direct immunofluorescence studies, and in that case, we can actually look to see whether there is antibody binding to the skin and where. whether there is antibody binding to the skin and where. Is it along the dermal-epidermal zone? And is it granular or is it linear? What's it composed of, what type of antibodies? And that then helps to sort of confirm the diagnosis.
DR. STERN: And can this be done by any dermatologist or is this a subspecialty kind of university procedure? [Dr. Stein] So the biopsies are done by anybody in their office, that's the bread and butter of what dermatologists do. And the regular pathology goes to any sort of pathology lab, though a lot of dermatologists are biased and want the pathology read by a dermatopathologist because there's a lot of subtlety, but the immunofluorescence is done in more limited locations.
DR. STERN: So I think most big commercial labs probably do do it, but there are specialty labs that do it and then most academic institutions have someone doing that as well.
DR. STERN: And it sounds like that's key to this particular patient, right? You won't want to just have the pathology without the immunofluorescence. [Dr. Stein] Right, the immunofluorescence really confirms the diagnosis. The regular pathology will suggest it strongly, but you need the immunofluorescence to confirm it.
DR. STERN: Sure, makes total sense.
DR. CIFU: And bullous pemphigoid has some interesting relations to other diseases, right? I feel like it's one of those things that when we make the diagnosis we're worried about is, does this portend something else? Malignancy or-? [Dr. Stein] So actually this is one of the conditions that doesn't have a known relationship to underlying malignancy.
DR. CIFU: Okay. [Dr. Stein] But it is associated- So it's more common in older people, so over 60, and then the incidence increases as ages go up from there. It's more common in patients with neurological diseases, anything from stroke to dementia, it's seen more commonly in that situation. And then there are a lot of other autoimmune diseases that it's seen commonly with such as diabetes, as our patient had, but also thyroiditis, lupus, rheumatoid arthritis, ulcerative colitis, multiple sclerosis, all of these diseases are seen in combination, one autoimmune disease with another.
DR. STERN: Do you think the association with age suggests that this is a myriad of conditions that are actually reacting to a drug? Because one thing that goes up with age is the number of drugs people are on. Is it thought that this is a drug-mediated phenomenon or thought that's usually not a drug-mediated phenomenon? When you see these folks, do you think about discontinuing medications? You're like, no, that's not really part of the- [Dr. Stein] So there are some clearly defined medications that have been identified as triggers, but it's not thought to be primarily a medication-induced eruption.
DR. STERN: Hm, interesting. I think pemphigus vulgaris is the one that's associated with malignancy. Is that right? [Dr. Stein] Um... Also not so strongly, not like dermatomyositis.
DR. STERN: Okay. [Dr. Stein] But it might be. I don't want to speak out of turn on that. There might be more of a reason to do a malignancy screen in pemphigus vulgaris, but pemphigus vulgaris definitely has much more mucosal involvement. Now, there are lots of subtypes of all of these blistering diseases, it's a very deep category. And so there are forms of pemphigoid which also affect mucosal surfaces, so there's a scarring type in the eyes, there's a type that preferentially affects the scalp.
DR. STERN: So there are a lot of subtypes of it and you can get really into the weeds with it.
DR. CIFU: I'm going to cut things off. [Dr. Stein] We'll leave it there. [all doctors chuckle]
DR. CIFU: Let's get back to our bread and butter here. So we're going to move on to fingerprints, common misconceptions, pet peeves, and clinical pearls. Scott, you want to start us out with fingerprint?
DR. STERN: Sure, I mean, the one that leaps to mind for me is the rash that's really a fingerprint for zoster. So when I see a vesicular rash that's in a clearly dermatomal unilateral distribution, that makes the diagnosis for me of herpes zoster when I treat those patients.
DR. CIFU: You go with VSV. I was going to go with HSV, I was going to talk about a group of vesicles on a red surface, usually painful, usually in the genital area as HSV. I guess HSV-2. Sarah? [Dr. Stein] Yeah. Well, so I think that the idea of fingerprints is a little bit confusing in dermatology. There are a lot of things that if someone describes it to me perfectly, I will identify it based on that description.
DR. CIFU: Psoriasis, for example, if they're well demarcated erythematous plaques with this adherent, white, micaceous scale, there's nothing that's going to be except for psoriasis.
DR. CIFU: It is interesting because when we talk about fingerprints, we're always talking about like a physical finding, an S3 speaks for congestive heart failure. I get the feeling listening to you that it is a clinical finding which is like pathognomonic for something but you are kind of considering a lot of things which maybe a less experienced, educated observer won't even notice the multiple things that are going into that fingerprint.
DR. CIFU: [Dr. Stein] Right, I think there are a lot of characteristics of each lesion that can be really helpful.
DR. CIFU: Cool. Common misconceptions, Sarah, you want to start this one? [Dr. Stein] I guess one thing that comes up a lot is, in terms of drug rashes, that people assume that they will happen immediately after exposure to the drug and that's really true only for re-exposures. So the first time someone's exposed to a drug, the drug eruption won't happen for about five to seven days. And I think that's sometimes something that people are surprised by.
DR. CIFU: I guess we see that all the time with ACE inhibitors causing cough, with amlodipine causing edema where you can take it for years before having the side effect, and it's probably that you're changing, your reaction to the drug is changing, whatever. Okay, Scott, you got a common misconception?
DR. STERN: I would just say, I'm going to steal one of Sarah's here and talk about topical steroids as- Because sometimes patients and providers have the sense that they're more potent than the oral steroids, and I think almost uniformly, if not completely uniformly, we would use topical steroids when we could over systemic steroids, and that's a common misconception.
DR. STERN: Is that fair, Sarah? [Dr. Stein] Absolutely. There's an amazing amount of steroid phobia out there, and it's steroid phobia for topical steroids. And sometimes this actually interferes with patients appropriately treating their condition, because they've been so told that these topical steroids have such dangers to the skin that they're applying them to.
DR. STERN: And you don't see those adverse side effects of topical steroids, unless you really misuse topical steroids and are using them on unaffected skin for long periods of time before something adverse occurs.
DR. CIFU: I guess my common misconception may be something that I kind of mentioned before that- And maybe it's actually, Sarah, how you ended your five key points. It's people who think that diagnosing a rash is sort of all about pattern recognition, and I think we've sort of beat this down already that there's a lot of kind of type two hypothetical deductive reasoning going on here, where you're considering lots of things not only about the rash, but about the patient that can be helpful in making a diagnosis.
DR. CIFU: Okay, pet peeves. Sarah, I think you are in the same camp with Scott and I, that you tend to harbor a lot of pet peeves. [all doctors chuckle]
DR. CIFU: So what do you have to throw out at us? [Dr. Stein] So I guess my big one is that term maculopapular that's out there. So the use of that word immediately makes one think that there hasn't been a careful consideration of what the lesions are. So I encourage everybody not to lump all rashes into that maculopapular word and rather pay close attention to the individual lesions and how they're distributed, and then make sure that you've done a full body evaluation, including scalp and mucosa and hands and nails, and get a full history and comprehensive non-skin exam as well.
DR. CIFU: I think maculopapular for the dermatologist is like decreased breath sounds for the internist, where you're just like, the hell does that mean? It either means the person has like bilateral pleural effusions to the apices, or it means that you don't know what the hell you're doing.
DR. STERN: And what we should clarify, so macular--
DR. CIFU: [Cifu and Dr. Stein chuckle]
DR. STERN: Wait, no, no, no, no. We haven't actually said, macular is flat. So when they're saying maculopapular, the reason that it's so disconcerting is, because a lot of lesions or rashes are flat and others are papular and while some maybe have both elements, when they're using that together, they're often just saying they haven't really looked at all. So that's what you're objecting to.
DR. STERN: [Dr. Stein] Yes, exactly. You can have macules and papules together, but say it that way.
DR. STERN: Right. So there.
DR. STERN: [tern chuckles]
DR. CIFU: I like it.
DR. CIFU: Okay, my pet peeve is a pet peeve which probably I mentioned over and over again, and it never sounds very patient centric, I got to figure out a way of saying this better, but especially with rashes, is really beware of accepting the patient's diagnosis. You have a lot of patients who come in with a rash and they say, "I have this," think spider bite or ringworm, where very often it's like, okay, I hear you, I hear what you're describing, but what's really important is for me to look at it and recognize that your spider bite is actually a Staph aureus infection or a ringworm is one of a thousand annular lesions.
DR. CIFU: Is that what you said? [Dr. Stein chuckles] Yes. Okay. [Dr. Stein] Yeah, I think that's a great point to make. And also that often patients will have decided that something caused their rash because we're always looking for reasons for things, and so it's important to not be misled by that either.
DR. CIFU: It's funny, that is like one of the great thing about the human mind, right? And it's why our species has progressed, is that linear thinking and attaching two things, but it really steers us wrong a lot of the time. Scott, got a pet peeve? Of course you have a pet peeve!
DR. STERN: Well, my pet peeve is pretty basic for the term, but it's shocking how often patients have a complaint that no one actually looks at. And there's been so many times when I've been precepting and someone has had a problem, and none of the providers actually looked at it. I think you have to look at areas which are painful, or people say there's a rash, obviously you want to look at it. So I was reminded of a patient who had knee pain and was wearing blue jeans and the resident hadn't actually looked at the skin, and when I asked the patient to lower their jeans so I could look at their skin, they actually had zoster.
DR. STERN: So I'm just a big advocate of if somebody points to an area under clothing that's bothering them, put your eyes on it, would you? Just, you know-
DR. CIFU: But were they skinny jeans that were hard to roll up?
DR. STERN: I don't remember, I'm afraid. [all doctors chuckle]
DR. STERN: I'm of the age group that doesn't know what skinny jeans are. What are those, Dr. Cifu?
DR. CIFU: Let's move on. Clinical pearls. Sarah, you have a clinical pearl for us? [Dr. Stein] Yeah, well, I guess, you know, I think it's important to keep in mind that rashes can look alarming. So if someone is covered in red blotches, that can look alarming to everyone, to the patient, to the caregivers, but step back and consider whether or not the patient is ill and let that help guide you in determining the urgency of the condition and the further evaluation that's needed.
DR. CIFU: We talked about that. I feel like I have the need to sort of bring up medical correlates to this, and one of the things that I remember we talked about when we talked about delirium, was that like a bad rash, delirium tends to freak everybody out too. And it's important to say, like, this is delirium. Is there anything concerning going on which is causing it or can I just focus on the medicine and not get terribly worried?
DR. CIFU: For me a clinical pearl sort of as an internist is to think about what's common. As a general internist, I kind of feel like my job is being able to identify and manage, at least initially, the common things that I see all the time. And that means kind of getting to know the bread and butter, the really common lesions that people come to the doctor with frequently, sometimes urgently, sometimes as "Hey doc, I also have this. What do you think of it?" And for me, that's something which I got to say didn't really develop in training, but has developed in practice.
DR. CIFU: And so what I certainly encourage people to do is, A, get good at that, B, when you see something that you're like, "Ah, you know, I kind of recognize this, but I don't know what it is," and you refer that person to dermatology, put that patient on a list that you can follow up, see what the patient had so you can really learn in your clinical practice over time.
DR. CIFU: And by the time you retire, maybe you'll be like 25% dermatologist or something.
DR. STERN: [tern chuckles] Boy, that's encouraging. [all doctors chuckle]
DR. STERN: But on those happy notes, I do think it's a great pearl, though, to follow up whenever you don't know what's going on on what happened to the patient, because you learn so much from those, you know, absolutely. The times I've learned the most is when I haven't known I've been wrong, right? And now with the electronic medical records, it's so easy to follow up and see what happened to someone.
DR. CIFU: Absolutely true. Absolutely true.
DR. STERN: Well, I have two pearls.
DR. CIFU: Really?
DR. STERN: Yes.
DR. STERN: I'm full of pearls.
DR. CIFU: Could almost be a bracelet.
DR. STERN: Could almost- [all doctors laugh]
DR. STERN: Wow, I've never heard that before. Okay, so the first one is, you may not be aware, but zoster can present without the rash, it can present with pain first. And so when you get patients who have a lot of pain in the chest or the arm or the abdomen, one of the things on the differential, even without a rash, is zoster. It can be troubling because it's often difficult to know for sure, but they often have hyperesthesia, they're tender, their skin feels tender to the touch and that can be a clue.
DR. STERN: And sometimes you just have to wait. I wouldn't treat someone like that, but it's interesting to know. And the other one, and I'd be interested in Sarah's thoughts about this is petechiae scare me. I think of vasculitis, I think of Neisseria meningitidis, I think of pneumococcal sepsis. Is that overblown or when you see a petechiae rash, does this also alarm you?
DR. STERN: [Dr. Stein] Yeah, I think vasculitic rashes are difficult and they're alarming. The differential diagnosis is vast for petechiae and purpura The differential diagnosis is vast for petechiae and purpura and there are whole experts, I think, within dermatology in that one reaction pattern, because it is so complicated. And I think, yeah, I think those patients do deserve special attention and a little extra urgency in figuring out what's going on.
DR. STERN: And if I can just clarify one thing with you, my understanding is when I see petechiae or purpura and it's flat and I don't feel anything, I think of thrombocytopenia as the primary problem or a platelet disorder. Whereas if it's palpable, then I'm thinking about the vasculitides and the infections. Would you agree with it? [Dr. Stein] Yes, I think that's a very good pearl.
DR. STERN: Okay.
DR. CIFU: We hope you found this episode of the Symptom to Diagnosis podcast useful and a bit enjoyable. A huge thanks to Dr. Stein for willingly accepting our invitation to be our first guest. We will give her some sort of parting gift, won't we?
DR. STERN: [tern chuckles] Okay.
DR. CIFU: Maybe a tube of topical steroids.
DR. STERN: [tern and Dr. Stein chuckle]
DR. CIFU: As a reminder, our textbook, Symptom to Diagnosis: An Evidence-Based Guide takes a much deeper dive into how to think about and reason through the diagnosis of medical presentations. The book is available in print, on your handheld device, and in a fully searchable mode via the Access Medicine website available worldwide from McGraw Hill. The music for this, the S2D podcast is courtesy of Dr. Maylyn Martinez.
DR. STERN: Thank you. [Dr. Stein] Thank you. [upbeat outro music] [upbeat outro music]