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Hi everyone.
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Welcome to Febrile, a cultured podcast about all things infectious disease.
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We use consult questions to dive into ID clinical reasoning, diagnostics
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and antimicrobial management.
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I'm Sara Dong, your host and a Med-Peds ID doc.
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I am looking forward to our episode today.
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We have three guests that are joining us.
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I will start with Dr. Tom Schmidt.
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Tom is a second year ID fellow at the University of Minnesota.
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He is interested in general ID, critical care, and the impact of a
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changing climate on infectious diseases.
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Hey, this is Tom.
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Uh, happy to be here
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Next I'll introduce Dr. Nate Bahr.
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Nate is an Associate Professor in the Division of Infectious Diseases
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at the University of Minnesota.
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His areas of interest include histoplasmosis, the changing epidemiology
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of fungal infections, drug pricing, and cryptococcal and TB meningitis.
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Nate is a co-chair of the Education Committee of the Mycoses Study Group
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Education and Research Consortium (MSGERC), along with Dr. Jessica Little.
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Hey, this is Nate.
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Excited to join.
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And rounding out our crew today is Dr. George R. Thompson.
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GR is a Professor of Medicine at the University of California Davis School of
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Medicine, and he has a joint appointment in the Departments of Medical Microbiology
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and Immunology and Internal Medicine in the Division of Infectious Diseases.
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He specializes in the care of patients with invasive fungal infections and has
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research interest in fungal diagnostics, clinical trials, novel antifungal
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agents, and host immunogenetics.
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Hey, I, I'm GR Thompson from UC Davis.
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Thanks for having me.
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Welcome.
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So as everyone's favorite cultured podcast, we love to hear about a
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little piece of culture, something that brings you happiness.
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So I, I generally think, uh, and most folks I think know this about me,
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one of the things that brings me the most joy besides my children is I
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absolutely love birds and birdwatching.
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My favorite birds are white breast and nut hatch, and the golden eagle.
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I literally recorded something earlier this week that they also said birding.
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Amazing.
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What about you, GR?
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Um, I, I spend most of my time chasing around my, my teenagers, trying to
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figure out where they are in the world.
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They've all picked up different sports that started during Covid, so I've
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had to learn a lot about lacrosse and, and my son's sort of an avid golfer.
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So by proxy, those are my three biggest interests right now.
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My wife though, is an avid bird watcher, so the red wing black bird in
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our backyard is frequently discussed.
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Yeah, I didn't realize the Venn diagram of ID and birding was, uh, so overlapped.
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Um, and then how about you, Nate?
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Well, uh, those birds could have been made up for all I know.
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So, I mess up your Venn diagram.
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For me it tends to be about my kids, outside as well.
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So, uh, I've had a lot of fun with them playing in the snow this winter
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and now it's getting warm, so we're enjoying that transition and, so I'm
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chasing them around and it's great.
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Love it.
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Yeah, spring is basically around the corner.
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It's almost here.
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Well, I wanted to start by just asking Nate to give folks a little introduction,
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because you had reached out to me with Jessica Little from the Mycoses
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Study Group, and I think that probably some of our listeners are involved or
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have heard of some of the initiatives and and work that the group's done.
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But I'd love it if you could orient people to that group and maybe let
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them know if they're interested, how they could get involved.
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So, Mycoses Study Group, um, it's actually the Mycoses Study Group Education and
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Research Consortium, which just as you can tell, it's, it's very short and easy.
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Um, but it does emphasize the correct things and, and those are
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big things that we're interested in.
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We wanna help further education around fungal disease.
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And so, this is part of that effort.
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We want to get information out that's important to, to clinicians
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related to fungal disease.
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We do that in a number of ways, but this is sort of an initiative to
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try to make sure we're doing that in any way that can reach people, and,
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and this reaches a lot of people.
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In research, this group has been involved in a lot of very important research
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studies over the years, and so, uh, a lot of the major figures that you're
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reading their papers in, in fungal diseases, many of them are involved,
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and often the Mycoses Study group has helped coordinate some of those studies.
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So if people are interested, they can go to the website.
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That's pretty easy to find.
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That's a good place to start.
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They can always email any of us as well, and we'll help send
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them in the right direction.
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But it's a group that, that, uh, is easy to become a part of and, and we're happy
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to have new members and get them involved.
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I realize what I should do is ask you if you ever abbreviate
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M-S-G-E-R-C and say it any other way other than Mycoses Study Group.
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I get confused, so no, I don't.
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Love it.
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Um, awesome.
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Well, Tom is going to take us through a case today, so I'm gonna hand over to him.
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Perfect.
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So we have a 50-year-old man who presented to the ED in the midwest US
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with a two week history of fatigue, low grade fevers, chills, and a new cough.
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Cough has been non-productive.
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No hemoptysis.
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He was previously prescribed a short course of antibiotics from an urgent
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care for pneumonia and given IDSA guidelines had done amoxicillin
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monotherapy at that point, didn't really make much of a difference in symptoms.
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And his history, mostly healthy.
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Has a history of hypertension, well controlled, type two
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diabetes, also well controlled.
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On exam, he is afebrile with normal vitals.
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O2 (oxygen) saturation on room air is 91%.
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On exam, some bronchi on auscultation.
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is otherwise unremarkable.
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We do get a chest x-ray that does show an infiltrate in the right upper lobe.
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So what do you guys think is going on?
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What would be going through your mind at this point?
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I think from my perspective, I guess as a fellow, certainly the things
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I would be thinking about are, do we have the right, diagnosis?
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In terms of if we're saying that this is a pneumonia, a bacterial pneumonia,
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generally if they got outpatient treatment, it may just be things
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like a monotherapy of amoxicillin.
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Um, are we missing the organism there?
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Is it something that's non bacterial?
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Is it a fungal infection?
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Uh, certainly I'd be less likely thinking of a viral infection, giving
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the two week duration of symptoms, or thinking of other, uh, like
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a parasite, something like that.
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So overall I would be thinking of a bacterial infection that's not being
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treated by what we prescribed or thinking of, uh, fungal infections
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as well, given the chronic or the two week course of symptoms.
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Yeah, I agree.
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I mean, I, I think when you get to two weeks, you start
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to question the diagnosis.
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Did we give an antibiotic that that missed the pathogen?
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Is this an atypical pneumonia?
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You know, two weeks is a bit long, but we've had, you know, big Mycoplasma
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outbreak over the last year.
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You know, pertussis still increases in frequency.
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Those patients, even with the right antibiotic, are gonna cough and
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feel bad for weeks or even months.
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I don't know much about the social history, but, you know, we talked
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about our love of birds, but, uh, you know, chlamydial infections, right?
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Maybe, you know, that have been missed with amoxicillin.
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I think there's a lot of possibilities.
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And we've brought up fungal disease and, um, you know, that's what I
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love to talk about, so I just will.
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But, you know, we've talked with the IDSA quite a bit about the pneumonia guidelines
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because they're pretty silent on the endemic mycoses right now, and if you look
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at the incidence, depending on where you practice in the United States, you know,
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there's, there's one paper that shows in Houston, Histoplasma is maybe 8% of the
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patients that come in with respiratory complaints in that particular study.
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Central Valley of California, it's up to, you know, a quarter of all
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CAP (community acquired pneumonia) is actually from coccidioidomycosis.
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And then Nate, if you want to comment, I don't know how frequent
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blasto is a cause of, of CAP, uh, up north, but probably not zero.
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So, um, yeah, so, so, so the, the big endemics, you know, we, we
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definitely consider and talk about.
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Yeah, and I think you're getting to a good point there, GR, because
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it, it, it matters where you are.
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Of course, risk is different depending on where you are.
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But we are starting to understand that our, notion of where you are with these
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endemic mycoses maybe is a little off and they're not, in some cases as,
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as restricted as we we once thought.
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So, you know, knowing where you are, but also understanding the patient's
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history a little better and, and if you haven't thought about them in a
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while, maybe that's a good time to go find some updated maps and data.
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They're out there.
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You know, while we're on that topic, would, would you maybe comment a little
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bit on some of the recent literature and, you know, knowledge about these
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expanding maps for endemic mycoses.
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So, for example, Nate, I've definitely shared the paper that you've worked on
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called Redrawing the Maps for Endemic Mycoses, and I try to reinforce the
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concept that we need to rethink these, you know, quote classic geographic
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boundaries and not take something off the differential entirely based on location.
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But I know there is also some thinking as well that for some of these papers, just
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because someone is diagnosed in a certain place, that that doesn't mean that the
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fungus is present in that environment.
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Um, but I think that's balanced with the fact that we clearly have signals that
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these fungi are an expanding locations.
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So how do you, uh, sort through that and, and think about this sort
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of spread of endemics as a whole.
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Yeah, so I, it depends on the approach.
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I think that's one thing to think about when you're looking at any
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of these sort of papers, right?
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So, our redrawing the maps for endemic fungi paper, that was all
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based on published literature.
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So that has an inherent limitation to it, right?
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So there's definitely cases happening that, that are not included there.
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There's also the, the very relevant point that simply having a case
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somewhere doesn't mean it's in the soil nearby or things like that.
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You need to know a lot more details, right.
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Um, you need to know while it's, it's interesting if you, if you found some
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cases of histo in Alaska, but did they, you know, just come from Kansas City?
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Um, that's pretty relevant.
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That's, that's all kind of important.
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You know, there have been some interesting things like, you know, histo has been
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found in soil in Antarctica, for instance.
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Um, so there, there is some of this where our, our sort of traditional understanding
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of this definitely has holes.
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I think it's probably right to both at the same time think, there are
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areas where the risk is much higher and there's also probably more areas at
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risk than we traditionally thought of.
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So I think one important take home would be if you're in an area where
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you think to yourself, well, it can't be cocci, because of where I live, it
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can't be histo because of where I live.
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That alone shouldn't totally rule it out.
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Um, it's part of the calculus, but you need to think of it a
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little more than just ruling it out because of where you live.
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That's my thought.
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Yeah, thanks so much.
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Well, Tom, can you update us on our patient.
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So the patient is able to produce some sputum, uh, which
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is ultimately sent for culture.
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Due to progressive symptoms, he is ultimately admitted and placed on
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broad IV antibiotic therapy with vancomycin and piperacillin-tazobactam
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and then azithromycin as well.
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He's noted to have a few intermittent fevers and ongoing cough.
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Sputum culture grows typical respiratory flora.
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A CT scan is obtained of the chest that shows a wedge-shaped
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peripheral nodular focus in posterior area of the right upper lobe.
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You get some additional history.
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He lives in the upper Midwest with his wife and partner.
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They have a dog and a guinea pig at home.
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He works as an architect.
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In the last year, he's traveled to Denmark for a vacation about six months ago.
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He also traveled to Florida for a work meeting.
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He has family in Arizona and most recently had a three week trip to
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visit family and meet his new niece.
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So you have some more social history.
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What do you guys think now?
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Yeah, so we talked a little bit about the differential diagnoses of these
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patients with non-responding pneumonia, and this really shows that that approach
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is essential because this patient, I mean, it's always hard to tell how ill
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they are in a, in a text-based format or discussion, but they've gotten sick
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enough to warrant admission with broad spectrum antibiotics, so presumably
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they've gotten quite a bit worse and that really shows that just taking
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a very detailed social history at times can avoid escalation symptoms.
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And then, you know, this can be a very costly admission.
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This is not stewardship savvy approach, right?
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They're getting vanc, pip-tazo, and azithromycin, for what could very well
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be an atypical or endemic pathogen.
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Azithro is gonna cover most of the atypicals.
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We don't hear uh, risk factors for pneumocystis or something like
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HIV or transplant or et cetera.
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So I think they're pretty well covered for, for most of the, the typical causes.
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But, but the endemic mycoses really aren't, aren't covered as far as
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their diagnostic approach or treatment.
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And then, you know, what do you get from a dog?
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Like, I don't know what kind of dog they have, you know, uh, kennel
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cough or, you know, parapertussis, I guess is in the differential.
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That doesn't seem like it usually warrants admission.
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Guinea pig.
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Nothing really comes to mind from respiratory causes of that.
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Guinea pigs are very allergenic, um, but, but doesn't really warrant hospital
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admission, then travel to Denmark.
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That doesn't really raise any red flags.
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Florida has a little bit of histoplasma, uh, down, you know, in the, I mean,
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histo is ubiquitous across the globe.
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Uh, you know, we, we commonly teach it in med school that it's just
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in this sort of Mississippi River Valley, but that's really not correct.
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But this history of travel to Arizona.
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Again, where in Arizona, you know, if it's, if it's up in northern Arizona,
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it's probably not any valley fever up there, but certainly Phoenix, you
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know, Tucson, Scottsdale, the, the real hotspots for travel and vacation.
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This three week timeframe certainly may have been exposed there.
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I don't know what time has gone by since he's returned to the Midwest,
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but that, you know, I'm gonna really wanna key in on that for, you know, some
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more details of his travel certainly.
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Uh, I got one thing to add related to the dog.
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So, dogs actually can sometimes, unfortunately, give very
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good clues for blastomycosis.
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I've it's at least more than one hand.
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Um, the amount of times that I've had patients tell me that their
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dog was sick with blastomycosis coming in with respiratory failure.
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So, they may not know they have it yet, but they know their dog
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had it, and that can be actually a really helpful history clue.
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Wow, that's so interesting.
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Well, how would you approach sending diagnostics up, right?
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Because we're talking about some of these fungal infections and have
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kind of this undifferentiated case, which, which tests should we send off?
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That's a great question and I think creates a lot of confusion,
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particularly if you don't do this all the time because there's a number
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of different tests available for coccidioidomycosis um, and you probably
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can't determine which one you send.
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It's probably just on the workflow of your particular institution.
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So most hospitals will send an EIA test first for IgM and IgG
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detection, and that's considered kind of a screening test.
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The CDC published their endemic algorithm for diagnostics just
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about six months ago or so.
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And if either of those test IgM, IgG, or both are positive by EIA, then
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you do additional testing with immuno diffusion and complement fixation.
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And the reason you do that is the complement fixation titer, um, is
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correlated with their symptoms, and also you can follow those
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serially over time prognostically.
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They, they do tend to correlate with the disease burden, so it can be really
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helpful for some of the vague symptoms that you're not clear if they're
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unrelated to their infection or not.
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The last test I'd mentioned is the cocci antigen test.
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For people who are immunocompetent, that's not a great test.
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Um, we typically reserve that one for people who are
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so highly immunocompromised.
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They may not make antibodies, so, you know, very, uh, immunocompromised
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states like solid organ transplant, bone marrow transplant, or,
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um, HIV with very few T cells.
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So that's really the group.
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We reserve antigen testing from the blood or urine
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In, in non-cocci diagnostics, I, I can add, with both Blasto and Histo,
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we can send antigen testing out.
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Blasto can often be caught with just a KOH prep on a respiratory sample.
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So it, it isn't perfect by any means, but it's pretty quick so that's a good thing.
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Um, particularly since many of these antigen tests we're sending out to get
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done and, and they can take a while.
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So those, those can be pretty useful, um, in, in this sort of patient too.
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And, you know, the patient lives in the upper Midwest and so in addition to the
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Arizona travel, I think that's important.
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Like the sort of geo geographic stuff is pointing us in a
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couple directions at this point.
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So for this case, when you examine this patient, like let's say we were
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talking through all these fungal infections, are there things that
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you're looking for on the exam to help you with the differential?
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I, I think definitely, you know, we've talked about the three major endemic
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pathogens in the United States, you know, histoplasma in an immunocompetent
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patient, they're really not gonna have oral lesions, some of those things.
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Blasto probably could have some skin lesions.
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Nate, feel free to jump in.
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You know, much more common to have skin lesions in those, in
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the immunocompetent patients.
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And then for Cocci with primary pulmonary pneumonia, which is
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what this seems likely to be.
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You know, if there's a rash that's, that really pushes you in the direction
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of coccidioides as the cause, or if you see an eosinophilia on their, uh,
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differential with their CBC, that's also gonna sort of push you in that direction.
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Um, so that's kind of the general approach to exam.
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you know, we haven't confirmed this as coccidioides yet, but if we do, you know,
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the next two things are to, to really check for risk factors for complicated
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infection or check if they already have complications of the disease.
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And so we do focus our, our exam on those findings as well.
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And what's like a typical skin finding for blasto that folks might see?
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Yeah, I, well, they can vary a bit, so I, I hate,
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I put typical in quotations.
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yeah, I don't know.
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I'm not in, that's a little hard.
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Um.
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They vary a bit.
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So the thing that should stick in your head is this sort of presentation plus
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skin findings, in a area with risk factors, blasto should be on the radar.
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Fair enough, so we do get labs and our diagnostics back.
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We have a coccidioides EIA positive IgM 1.8.
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Uh, IgG 4.0 and positive is greater than or equal to 1.5.
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Coccidioides antibody by complement fixation is positive at 1:8.
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Other testing is obtained.
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Interferon gamma release assay, cryptococcal antigen, histo and
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blasto antigen and serologies, all of which are negative.
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So, yeah, thanks for those labs that, that's helpful.
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I think that really does help firm up the diagnosis of primary
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pulmonary coccidioidomycosis.
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You've got a positive IgM and then you've already got a
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complement fixation titer of 1:8.
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So that really suggests exposure has been more than three or four weeks ago.
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Um, so I guess that sort of fits with his, his trip to Arizona, and then so the
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titer of one to eight, that's also sort of consistent broadly with someone that
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might warrant admission to the hospital.
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It can have a ref reflects a, a fairly significant burden of disease, but
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titers are really most helpful to follow in a single patient longitudinally.
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So a titer of 1:8 different patients may manifest quite differently.
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So it's not quite as predictive.
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We do know that titers above 1:16.
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32 or higher, 50% of those patients are gonna have disseminated infection.
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So that's a group really to focus on if they have high titers.
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There's a tremendous difference in what lab runs your titers.
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So labs that do a micro titers, so those would be the big reference
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labs, ARUP, Quest, et cetera.
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Those titers on in general run higher than the more specialized cocci tests.
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So, um, you can't compare one lab's complement fixation
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test to a different labs.
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It needs to be done at the same, same location.
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And then the general approach, this patient was uh, 50, so, you know,
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um, uh, I'm almost 50, so that's just barely middle aged now, I guess.
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That that's not really associated with, with risks for bad infection by age.
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Uh, we know patients older than 65 have a rougher time, just like with almost every
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infection, but this is a, a male patient, and we do know that males versus females
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have a, about a six to one ratio of, of coccidioidomycosis, uh, acquisition.
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And the reasons for that are unclear.
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We've, we've wondered if that's, you know, sociologic, just differences
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in hobbies, occupations, et cetera.
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But we've actually looked at our veterinary animals and a primate cohort
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and saw the same thing across the board.
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The male primates, male dogs all acquired, you know, cocci at a greater rate
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than the female, uh, dogs or primates.
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And then if, if the dogs were actually castrated, they're, they're
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risk return to the same as females.
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So we do think it's probably biologic.
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And we know that cocci uses a number of different hormone receptors.
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It can probably use those as either growth factors or carbon sources.
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Um.
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And so we think that's the major issue is just the testosterone.
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Men, we hate to admit this, our immune systems are weaker.
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That's why we get things like man flu.
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Um, also that the sex hormones, you know, the second and third trimester of
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pregnancy, when, when women have higher estrogen levels, that's also a risk
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factor for bad infection with cocci.
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We see people disseminate, uh, in their second and third trimester of pregnancy.
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So all those are things we kind of consider.
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This patient wasn't described as immunocompromised.
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We do know that, that sadly not only has this sex predisposition for
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bad disease, but there's certain, genomic ancestries, you know, those
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from Oceana, like our Filipino patients, Marshall Islands, et cetera.
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They, they have risks for, for worse outcomes with cocci as do our
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patients of African genomic ancestry.
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The genetics of that have been, uh, worked out a bit.
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Uh, probably about 50% of the patients have been explained some really great
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work done by the NIH, uh, Steve Holland and Amy Sue did a lot of that work with,
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with sort of our patients in a group from Arizona, but there's still a lot to
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learn, you know, how do we predict these?
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And even all those risk factors we understand, we still examine
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these patients really carefully.
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Image anything that hurts, kind of approach 'em like Staph aureus, if it
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hurts, look at it more closely, and, and just check for complications.
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So that's kind of our big picture approach to these patients.
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Well, maybe what we can do is also talk about treatment options and
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general thoughts on, on therapy.
:
Yeah, I think, I think therapy in our, our view of treatment is, it depends who
:
you ask in the field of, of coccidioides.
:
So there's sort of two camps, you know, there, there's sort of
:
a group of physicians that say, well, most patients historically
:
did well even without treatment.
:
So if they have pretty mild symptoms, maybe don't treat 'em at all.
:
I think this patient's different.
:
They're clearly sick enough to be in the hospital, so they're
:
gonna need antifungal therapy.
:
Generally most patients start on fluconazole.
:
Um, in vitro that's probably the least effective drug, probably a mold active
:
azole, itra, posa, vori, isavuconazole.
:
All those are more effective in vitro. You know, we have only one comparative
:
study looking at fluconazole versus itra.
:
The itra patients generally did better, but our approach would be to
:
start this patient on fluconazole.
:
Generally a higher dose, more like 600 or 800 milligrams per
:
day if they're a 70 kilo person.
:
If they don't respond over just, you know, several weeks or a month, or if
:
they have side effects, which a lot of the patients do from fluconazole, alopecia,
:
cheilitis, xerosis, all that sounds benign until you've gotta deal with it
:
for a while, you know, we're pretty quick to put them on a drug that we think has
:
fewer side effects and more efficacy.
:
So, you know, itraconazole, this is a 50-year-old, you're not too worried
:
about heart failure yet, but, but that's definitely something to think about with
:
itraconazole, uh, as a negative inotrope.
:
Posaconazole, uh, looks at least in vitro, like it might be the most effective azole.
:
Does cause hypertension, and about a third of patients causes a
:
pseudo hyperaldosteronism syndrome.
:
Voriconazole, if you think about the regions that have cocci with, with Arizona
:
and California, there's a lot of sunshine.
:
So putting patients in those regions on vori as a photosensitizer can be
:
really difficult and in long-term use skin cancer, of course.
:
And then isavuconazole, we don't have as much data, but we've used a lot
:
of that, very effective and, and very benign, uh, doesn't tend to have a
:
lot of side effects with that drug.
:
So that's, that's our general approach.
:
I probably wouldn't give this person amphotericin B, I mean, again, it's
:
kind of hard to tell how sick they are you know, this, this format, but unless
:
they really are, are compromised from a respiratory standpoint, um, I'd probably
:
try to give them an azole and tell them, you know, over the next few weeks you
:
should start feeling better and improving.
:
And then I'd really look out for the development of erythema nodosum.
:
When they have that, that's a favorable prognostic sign.
:
It's a panniculitis, inflammation of the fat, typically on the shins.
:
We do see it on the forearms as well.
:
And that's not disseminated infection.
:
That's a sign that you've, you're starting to develop Th1 immunity to
:
the underlying, coccidioides species.
:
So, so those are all the things we approach in kind of that
:
first, you know, four week window.
:
So how do you decide on, uh, approaching CNS disease?
:
That's a great question.
:
'cause even uncomplicated pulmonary infection, they often have headache.
:
In the past if they had a high titer, everyone received a lumbar puncture
:
looking for disseminated disease.
:
One of our fellows wrote a paper about that a number of years ago and showed
:
if your headache is not changing in character, you know, more frequent
:
escalating in severity, timing, et cetera, and you have no other CNS symptoms, it's
:
not worthwhile to do a lumbar puncture.
:
You're just gonna get negative results.
:
And that was a multicenter study that, that sort of changed the
:
dogma associated with that practice.
:
We really need to find a good reason in adult immunocompetent
:
patient to do a lumbar puncture.
:
I mean, we think of those as fairly benign, but CSF
:
leaks are, are fairly common.
:
That's, that's sort of morbid for the patients.
:
That causes more headache, that definitely won't help them.
:
Um, so we, we try to only do that for people we really
:
feel like we're gonna help.
:
How about somebody that is more immune compromised?
:
Does that change your thoughts?
:
Definitely does.
:
If, if they're immunocompromised, we definitely have a much lower
:
threshold to do a lumbar puncture.
:
We still approach it generally the same.
:
They need to have a compelling reason, you know, some kind of a symptom
:
that's correlated with CNS infection.
:
We, we don't just do those on a routine basis like we do with cryptococcus, right?
:
Any crypto infection, they get a lumbar puncture for the most part, but
:
we don't tend to do that cocci, but I'd say we have a very low threshold.
:
GR knows my crypto background, so he knows that I'm lumbar puncture happy.
:
It's all right.
:
We love a good lumbar puncture, but we also try to avoid them
:
after we've caused some CSF leaks.
:
And I guess one other tangent that I'll ask is, let's say this patient
:
wasn't responding or you know, is running into issues down the road.
:
Is resistance common?
:
Is that something that we should be worried about?
:
So patients who don't respond to therapy are pretty interesting.
:
It's, it's fortunately, a fairly small group that doesn't
:
respond to a second triazole.
:
We mentioned we'd start with fluconazole probably, and then maybe a second
:
triazole later without a response.
:
But patients that don't respond to a second triazole are maybe
:
10 to 15% of those patients.
:
I think the field has always said resistance doesn't really occur in cocci.
:
To me, that seems sort of odd.
:
Why would cocci be such an outlier that there's no resistance?
:
Certainly clinical resistance occurs, you know, even if it's in vitro,
:
it's supposed to be susceptible.
:
The patient may not respond, but I think the good news is we have a number
:
of new drugs sort of on the way that are in phase two and three trials, and
:
so it'd be olorofim and fosmanogepix.
:
The bad part of that though, is some of the environmental antifungals that
:
are put down to deal with things like alternaria with almonds, uh, you know,
:
aspergillus on peanuts, et cetera.
:
So this other drug ipflufenoquin actually works just like olorofim
:
and uh, aminopyrifen works just like fosmanogepix, so if we put those down in
:
high concentrations in the environment, we may actually lose susceptibility
:
to these fungal pathogens before the patients have even seen the drugs.
:
And with that, we're really hopeful that some of these silos
:
of regulatory authorities can get on the same, same page.
:
And, and they really have.
:
The CDC has has led that with the EPA to try to break down some of
:
these barriers where, what's approved for the environment, you know,
:
the, the, the true One Health one world effects can be evaluated to
:
prevent, uh, spread of resistance.
:
And, and, you know, we've been very ahead of that game over the last,
:
you know, 20 years with antibiotics and chickens and those kind of
:
things, but we sort of neglected antifungals on our agricultural crops.
:
So this recent consortium is gonna hopefully solve that problem, but
:
it it still gets at the question, we're always gonna have resistance.
:
You know, we're in a constant battle with all these microbial pathogens.
:
We create a new drug, they figure it out over time.
:
You know, I'm always reminded of penicillin resistance was described in
:
the lab before a patient had ever seen penicillin during the advent of that.
:
So we, we, we need to really continue to search for new drugs because this
:
is gonna be an ongoing war forever.
:
Yeah.
:
So, you know, and that's, that's a great point because, of course many
:
of our new drugs come from, from very basic research at the beginning, right?
:
So new mechanisms are discovered, and they eventually lead to a drug discovery.
:
So, you know, this is a, a, great sort of segue to, to simply state
:
that we need definitely continued investment in, in mycotic diseases.
:
It's interesting when I started doing research as a fellow, I started working
:
in in crypto meningitis and I, I was sort of shocked at how relatively
:
little research was done compared to some other things that I knew about.
:
and then I started getting interest in TB meningitis and I thought,
:
wow, crypto has it really good.
:
I. And then I got into doing blasto and, and I've realized that there is somewhere
:
to go with less and less investment.
:
So, um, we need to learn a lot about this stuff and we need
:
continued investment in science.
:
Um, this is, this is the only way we're gonna continue to find out better
:
ways to treat things, better ways to diagnose things, who's at risk.
:
It's not time to, to stop.
:
We need to continue to invest.
:
Yeah, that is such an important point.
:
Tom, any other questions that you have?
:
. Thinking more generally, it's important for us to think about the intersection
:
of infection and climate change.
:
We'd love to hear from the both of you, uh, any insight you have into
:
how many of the recent wildfires might impact coccidiomycosis.
:
Yeah, that's a great question.
:
We really had, had thought a lot about wildfires, particularly during covid.
:
You know, we're cooped up in the house and then it starts
:
being smoky every everywhere.
:
And we affectionately called that "smovid" in, uh, California.
:
But during that time we started to really think about the amount of debris that
:
was being deposited by the wildfires.
:
You know, you could just walk out on the sidewalk and see
:
debris from, from the smoke.
:
And the particulate matter we had started to question, does this
:
actually carry living organisms?
:
And in conjunction with Leda Kobziar and her group who studies this,
:
she actually flies drones over wildfires to collect smoke samples.
:
Found that there is this living component of smoke and founded this new field
:
pyroaerobiology and you know, is published on that in Science a number of years ago.
:
You know, has found really a a who's who of opportunistic fungi with that, you
:
know, um, cryptococcus, cladosporium, mucorales, aspergillus, et cetera.
:
Has not found cocci in that, so that does create the question, you know,
:
uh, fire does create its own weather.
:
It sort of pulls smoke through the surrounding soil and vegetation
:
and can pull that up, you know, even into the upper atmosphere.
:
And, and maybe one of the ways pathogens travel very long distances.
:
But cocci requires drought as part of its lifecycle.
:
Fire obviously needs drought just to start large fires.
:
It does cause the question of these just true, true but unrelated.
:
And then the, the group at UCSF has published a nice paper just
:
a few years ago that did really show this correlation that.
:
They published that I think in Lancet Planetary Health using administrative
:
data from a number of hospitals and did show this very close correlation
:
between wildfire smoke and the number of coccidioides cases.
:
So we do think there's a close association.
:
We know firefighters get a lot of cocci.
:
Unfortunately a lot of the firefighter service is, is, you
:
know, California prisoners out here.
:
Um, and it's just hot.
:
They don't wanna wear protective gear.
:
It's too hot to, to keep that on.
:
They're, they're not actually out there putting out the fire, but they're
:
doing high risk activities like cutting fire breaks, you know, they're deep
:
down in the soil or, or digging up a lot of soil, potentially exposing
:
them to, spores in that environment.
:
so, so it's, it's a confluence of a number of factors, you know, we think, but an
:
area that's ripe for additional work.
:
Those papers are so cool.
:
I've, I've pulled some of them for, for puscast and, um, just
:
like found them so fascinating.
:
Oh Leda flying those drones over stuff.
:
It's cool.
:
Yeah.
:
That's very cool.
:
Yeah.
:
Nate, is there anything else that you wanna add?
:
Um, do I want to add something?
:
I mean, for cocci, I, I don't, I mean, I, you know,
:
I,, can only say cocci.
:
I can't say the whole thing, uh, without stumbling so
:
No one can.
:
It's impossible.
:
do you, do you wanna talk about hurricanes and mold or, uh,
:
tornadoes or any of that stuff?
:
Yeah.
:
Before I, I came back to Minnesota, I was in Kansas City and not long before
:
that, um, there had been a really big tornado in, in Joplin, Missouri.
:
And after that there was an amazing amount of, of sort of rare mold
:
infections, things that people weren't used to seeing very often, but were
:
seeing quite frequently after that.
:
So these, you know, these weather events, when they do things to soil,
:
they, they tend to carry mold with them.
:
And so it's, it's sort of an important point to think of if
:
something like that, you know, if, if some big weather happening in your
:
area, you're pretty likely to see more of that sort of thing happen.
:
Thanks so much to Tom, GR, and Nate for joining Febrile today.
:
Hopefully this got you excited to hear about fungal infections, so you can check
:
out the Mycoses Study Group Education and Research Consortium for more learning.
:
Their webpage is posted on the website as well as in the episode info.
:
I also encourage you to check out a recent webinar that had Dr. GR Thompson,
:
who is here with us on the episode, as well as Dr. Fariba Donovan, talking about
:
cocci in the aftermath of the wildfires.
:
So we will put a link to that webinar, which was, um, hosted just this past week.
:
You can check out the website febrile podcast.com to find the Consult Notes,
:
which are written supplements to the episodes with links to references,
:
our library of ID infographics, and a link term merch store.
:
Febrile is produced with support from the Infectious Diseases Society of America.
:
Please reach out if you have any suggestions for future shows or want
:
to be more involved with Febrile.
:
Thanks for listening.
:
Stay safe and I'll see you next time.