DIP Episode 631 - Travel Medicine Part A (super HY with numerous integrations, for Step 1-3)

All right, welcome. My name is divine. This is episode 631 of the divine intervention podcasts and into these podcasts We're going to be addressing a topic I title travel medicine This is going to be a two-part series because it's just going to be too much to load into one podcast Okay, it's going to be a two to three part series But I'm going to try to keep it to two parts And the thing about travel medicine is number one It tends to contain a bunch of obscure things Number two, these obscure things tend to show up a lot on the USM in the exams number three If you just know a few key things, you're going to be pretty good to go with these topics and then number four The USM is they really do want you to emphasize mechanisms in your understanding of these topics, okay? So we're going to try to address this in a format that's going to be very helpful to you for your USM in the exams all right So First things first what if they give you a question about a patient that is about to travel to someplace and requires pre-travel vaccines How long before traveling should those should you give those people those necessary vaccines? Well, I hope you're picking the answer choice that talks about two to four weeks right two to four weeks The thing is you want to give these vaccines two to four weeks before the pressing travels why?

Because you want them to amount and adequate antibody response You want them to mount an adequate antibody response And the thing is sometimes you may even have to stretch out that timing to longer than four weeks if it's a vaccine that requires Multiple doses that's something you definitely want to keep at the back of your mind for your exams, right? And again In thinking of this topic just think of the population you're giving the vaccine to right so just be mindful of that right So like for example if a person is immunocompromised less in the acidity for count is less than 200 or The person is pregnant right or the person has some kind of immunodeficiency disease You would know to not give them a live-attenuated vaccine, right? So something like the yellow fever vaccine that will not be smart or a person like the oral typhoid vaccine that's live-attenuated Right, I mean yeah, that's that's live-attenuated right or the MMR vaccine right things like that Don't give it to those people those special populations people under age one people that are pregnant People have CD4s under 200 right or people that have immunodeficiency diseases. No, it's not gonna be a smart idea for those people, right? But then you know many of the other you know vaccines right like the inactivated vaccines things like hip A, hip B Right typhoid the injectable one right so don't mess this up on your exams, right? The oral typhoid has two kinds of vaccines.

There's the oral one and there's the injectable one the oral one is live-attenuated the injectable one is An inactivated vaccine, right? It's an inactivated vaccine. So for persons you may not compromise Don't give them the oral typhoid give them the injectable typhoid vaccine again It's little details like this that kind of mess people up on their exams, right? So just something to keep in mind for your for your test All right, so I think the first bug we should talk about probably the one that is tested the most frequently is malaria Right, so let's talk about malaria, right? So we know that malaria again Having mosquito netting is very very helpful in prevention, right? Having mosquito netting is very very helpful in prevention, right? That's a very simple thing to do very very helpful in prevention, right? Very very helpful in prevention Right in fact that's gonna be a method of Primary prevention, right? You basically like have the net, right? You know like a pesticide-treated net and then that reduces your risk of being bitten by the anophilus mosquito, right? Remember, malaria is caused by the plus modium species and those plus modium species are carried by the anophilus mosquito, right? By the anophilus mosquito, right?

So one classic thing they love to do on the US Emily exams is that they love to test the drugs Use for malaria pervillaxes and sometimes they love to test the mechanisms of action of those drugs and they're not just only the mechanisms of action of those drugs But the contraindications to those drugs you absolutely need to know this for you exams So the drugs used for malaria pervillaxes the contraindications to those drugs and some basic mechanism of action detail on those drugs, right? So like for example the first one is gonna be a tovacoan proguenial That is like a very classic one details on the exams at tovacoan proguenial, right? Basically this one it does two things, right? It inhibits the electron transport chain and it shuts down for its synthesis, right? And the reason that this is probably like the most common one tested on the US Emily exams is that there is very little resistance to it But if you have bad kidneys you have no business being on a tovacoan proguenial, okay? If you have bad kidneys, you better not be on it another classic one you miss your exams is Mephluquin Mephluquin don't worry about the mechanism of action for your test But this one they love it just think of mech fluquin as the contraindicated in the crazy, okay? Think of it as being contraindicated in the crazy. What do I mean by that? If you have a history of like a seizure disorder, right or psychiatric condition, right? Do not take Mephluquin, right?

And also if you have like cardiac conduction problems, right? Like you have like AV neuro disease for example Mephluquin is not a good idea at all. Now is there are there some other Drugs on the US Emily exams that are not necessarily for my Luria But are kind of like neurotoxic to raise like Maybe you want to be careful about giving this to people that have a history of like whatever's you want to think about Interfernal alpha interferon alpha is a big one remember we use that to treat hep C If you have a history of like measure the pressure disorder or suicidal ideation I mean to for an alpha is maybe not the best idea, right? Maybe not the best idea in those circumstances, all right? Let's keep going right and then doxycycline Great doxycycline remember this is a 30s inhibitor, right? It's a 30s inhibitor is a 30s inhibitor is a 30s inhibitor That's something you absolutely need to know for your exams for so it's a protein synthesis inhibitor, right? I remember doxycycline Is okay in kids you can give it to kids even under age eight, right?

But again the US Emily's they are still Larry of you giving doxycycline to people That are pregnant right the US Emily's they don't really like doxycycline in the pregnant right just something I want to keep at the back of your mind on you exams Just want to keep at the back of your mind for you exams and there's not much resistance to doxycycline Doxycycline is pretty it's pretty effective now One thing you want to know about doxycycline is they can give you a question about a person that took doxycycline For malaria prophylaxis right and then they travel to a tropical area and then they tell you that they've been having this skin Rush that seems to worsen whenever they go on the beach whenever you see that I would really hope you're thinking about the Foto sensitivity that goes with tetracycline Okay, it is very high yield for purposes of your exams to know the drugs that cause photosensitivity There is a very nice to money you've probably heard from back in the day called sad for photo Sad for photo the S stands for so phonomites the East stands for a Mute Roan and the T stands stands for tetracycline Right those drugs are straightover photo sensitivity, right? And then there's some other disorders you miss your exam so that's really photo sensitivity, right? So things like Chidiaki Gashi, right photo sensitivity Things like Lupus also are so photo sensitivity, right?

So just something you want to keep at the back of your mind for your for your test All right, and then let's go back to the malaria drugs and then chloroquine right chloroquine Um, the key thing to know here is there's a lot of resistance a lot of resistance and it pretty much inhibits Hym synthesis right in the in uh in uh plus modium species, right? But again, there's like wide wide wide widespread resistance wide wide wide spread resistance However, one high yield thing you want to know for purposes of your exams is that chloroquine can cause a ethnopathy Right when you use chloroquine chronically, it can cause a ethnopathy Is there another drug that it kind of sounds like chloroquine? I can also cause a ethnopathy I hope you're saying yes, that's gonna be hydroxychloroquine, right? The thing that everybody thought could magically cure uh COVID, right? Even if it doesn't really do that um or it does it to a limited extent But hydroxychloroquine also causes a ethnopathy, right? Remember hydroxychloroquine is one of these drugs Uh that you can actually use to treat like rheumatoid arthritis and people that are pregnant, right? Because remember if you have arianne, you're pregnant Maybe it's not a good idea to take methyl trixate, you know, you probably don't want to kill the baby right? So, I mean that's where comes times you want to consider uh using hydroxychloroquine It is safe in pregnancy, but remember hydroxychloroquine can absolutely cause a ethnopathy Okay?

Hydroxychloroquine can absolutely cause a ethnopathy, you need to know that for your exams And one other thing I'm gonna say about malaria before I kind of wrap this up with malaria Is don't forget many of these uh malaria drugs, especially primal quit remember Primal quit is a drug we can use for malaria, right? But under use is, you know, to kill the dormant forms that can stain the liver like Plus modium, vivax and ovali, right? Those hypnozoid forms they can stay dormant in the liver Uh primal quit is pretty good for those, right? But remember primal quit is a very powerful oxidizing agent, right? So the thing is because it's a very powerful oxidizing agent It's not a great idea and people that have g6pd deficiency, right? So they can give you a question about a person that's about to initiate Primal quit therapy and then they can ask you like, oh, what is the most appropriate next best step in management? Are you want to pick the answer that involves uh screening them for g6pd checking their g6pd levels? Right? Or they can give you a question about a person that is given primal quit And you know a few days after they get the primal quit Uh you notice that they have an increase in their inter-indirebular vein Right? And you notice that they have like jaundice Uh and then they can ask you about the mechanism behind their symptoms, right? You can talk about uh impaired regeneration of gluthertion, okay?

Pick the answer choice that talks about the impaired regeneration of gluthertion Let me tell you something here, right? I know some of you may be like divine Why are you talking about impaired regeneration of gluthertion? Couldn't it make it simpler like um g6pd deficiency or impaired NADP-ish production? To be honest with you if that's what they did on the exams Everybody will get a 270 on the exams Clearly that does not happen You know why that does not happen? Because that's not how they test information Right? On the USMELY exams, they test information with the priority to see If you can think beyond just the surface level Right? If you can think beyond just the surface level Right? Because remember the reason why g6pd deficiency is such a problem And by the way, remember it's it's excellent recessive, right? So it's going to be like a man problem on your exams, right? But the primary problem is that if you Have a deficiency of glucose 6-4-3 D hydrogenase You're not going to be able to make Um NADP-ish And NADP-ish is necessary for gluthertion regeneration Because remember gluthertion is the thing that helps us de-woodoxidative stress Right? Helps us de-woodoxidative stress So they want to keep at the back of your mind for for exams Right? Now let's jump on So talk to one malirium Trying to again hit the high-yield things Um let's talk about travellers diarrhea Travelers diarrhea is another very common thing you may see on your test Right?

Now one classic thing when I keep at the back of your mind is this What is the most common cause of travellers diarrhea? What is the most common cause of travellers diarrhea? It's going to be ETEC, right? Enterotoxigenic Ecoline Enterotoxigenic Ecoline Right? And the thing is Typically is going to cause a watery diarrhea Right? But the thing is there is one point of contention Our friends at the NBN is like to bring To basically kind of throw you for a loop on your test So basically kind of throw you for a loop on your test And that's something I think I want you to Keep in mind for your for your exams, right? What is that thing? The thing is Giaordia can also cause a travellers diarrhea, right? Giaordia can also cause travellers diarrhea And sometimes the presentation can be almost identical to ETEC So one classic thing people ask me is Define How can I differentiate Giaordia As the cause of travellers diarrhea from ETEC As the cause of travellers diarrhea Look at your timeline If the person has travellers diarrhea that is lasting for just a few days Think about ETEC Think about enterotoxygenic Echoline But if the person has travellers diarrhea that seems to last for weeks And then you see an antecedents of like Stiadoria Like Fatma absorption like Fat in their stool You want to think more along the lines of Giaordia You want to think more along the lines of Giaordia I may wonder like divine What is the mechanism? Why does this happen?

Well the thing is Giaordia Literally damages Your intestinal mucus It literally damages your microbiology If you damage the microbiology Do you think you're going to be able to Reabsorb things very well? Not really You're not going to be able to reabsorb things very well at all So if that happens You're going to have my absorption And Stiadoria is a very good finding in my absorption And then you're like Divine why does it last so long? Well the thing is It kind of takes the body a little bit of time To clear Giaordia And also after Giaordia has destroyed your microbiology It takes a while for those microbiology to get regenerated So that's why their symptoms tend to be a little more long Lasting Again if you understand the pathophies like this You're not just like mindlessly memorizing details Alright now let's develop a little deeper on E-Tech Because again classic thing they love to test on the exams is Hey how does E-Tech cause problems for you? E-Tech does not necessarily damage your microbiology So it doesn't cause my absorptive problems What it does is that it has two toxins It has a heat libal toxin And a heat stable toxin And the heat libal toxin Heat libal toxin What does it do?

The heat libal toxin activates At any late cyclists When you activate it, it doesn't need cyclists You're going to make a converted ETB to cyclic AMP You're going to stimulate protein kinase A And that's going to cause you to dump a lot of chloride ions Into the lumen of your GI tract As you dump all the chloride ions into the lumen of your GI tract It's going to attract water And then that's going to cause you to have diarrhea The heat stable toxin is going to activate guanilit cyclists It's going to activate what guanilit cyclists Guanilit cyclists When you activate guanilit cyclists You're going to convert GTP to cyclic AMP And then cyclic AMP is going to activate protein kinase G And when you activate protein kinase G You're going to make a lot of You're going to also again secret a lot of chloride Into the lumen of the GI tract So water is going to follow And you're going to have diarrhea But let me ask you this What kind of diarrhea is this? What kind of diarrhea will that be? It's going to be a secretory diarrhea Because that's the mechanism behind the diarrhea Right? A lot of chloride ions are being secreted into the lumen of the GI tract And then water is following And then you are having diarrhea So it's going to be a secretory diarrhea Contrast this with a person having garedial diarrhea That tends to be more of an malabsorptive diarrhea Okay?

So again, on your exams They can literally give you an E-tech question And instead of putting E-tech as the answer They'll just put secretory diarrhea as the answer Or on your exams they can give you a G-r-dial question And instead of putting G-r-dial as an answer They will just put malabsorptive diarrhea as the answer Again, please be aware of surrogates Basically, I like to think of the USML Is as follows I like to think of it as an exam Where they want you to know as given concept in six different languages Right? Because they can present any of those six different languages But the thing is you may ask yourself divine How am I able to pick up on these six different languages Honestly, the best way is to just understand pathophysiology The thing is when you understand pathophysiology It's almost like you understand how those six different languages were created Right? So if they give you an example that is novel on usual Many times it's still going to reflect that on the line pathophysiology That you should have understood in the first place Okay? So again, remember, E-tech mostly causes a secretory diarrhea It's going to be a watery diarrhea They're going to have a lot of cramping Right? And typically when you check those people's tools You're not going to see white blood cells You're not going to see blood in their stores And how do we treat E-tech? Well, you can treat E-tech with a fluoroquine alone Or you can use E-thromycin plus lupyramide Right?

A fluoroquine alone Or E-thromycin plus lupyramide Remember lupyramide is a weak, mu opioid receptor agonist Right? So that can help the diarrhea by basically causing a mild constipation Right? And then remember, GRD again Long-lasting diarrhea is going to be greasy Right? signs of abnormal absorption They're going to have blood in They're going to have fast-melons tools And we're going to manage that with metronidesol Or T-need-osol Right? And then if you see a person That has bloody diarrhea And it's travelers diarrhea I really want you to think of Campylo-bacter Or think of Shigella Think of Campylo-bacter or think of Shigella Believe it or not Even if many times these are tested in terms of mainstream gastroenteritis They can also be tested on the USMD exams In the context of bloody diarrhea Travelers diarrhea Okay? So keep that at the back of your mind for exams Right? So like for example, Campylo-bacter If they give you a question about a person that has bloody diarrhea And then they tell you that the person has like lower extremity weakness Then I want you to think of that person having Campylo-bacter Uh, Gijunai infection Right? Because that lower extremity weakness tells you that Ooh This person has Guillembris syndrome Right? Guillembris syndrome And again, we're going to manage it with Is it thromising or you can use a fluorocuenolone Right?

Again, if you're Uh, I want a no-in-thin offerings that the NV Mes can do Is they can give you both as answers They can give you is it thromising as an answer They can give you a fluorocuenolone as an answer If they give you both as answers Which one should you pick? The USMD is totally do this to people all the time They'll give you two right answers that work for the question But one is a better answer than the other If you see those, pick is it thromising Pick the markedly answer Why? Well the thing is there is less resistance to markedly It's compared to fluorocuenolones, that's number one Number two, fluorocuenolones have a lot of toxicities Right? They can do things like explode your Achilles They can cause an Achilles tendonopathy And they can also prolong the QT interval The only problem you're worried about with is it thromising is that Hey, this could prolong my QT interval But at least it does not explode your Achilles And there's not as much resistance as we have with fluorocuenolones All right, and then Shigella Right? Shigella, again, bloody diarrhea Very high fever Right? They may have signs and symptoms of the hemolidic uremic syndrome So if you see a person having bloody diarrhea And they have like big-time thrombocytopenia Right? They have big-time thrombocytopenia Right?

They have like elevated creatinine They probably want to think more about Shigella As the cause of their travellers diarrhea As against Campylobacter Gijonai And again, you can treat this with a fluorocuenolone or is it thromising Right? So hopefully like you're beginning to see kind of a trend here Many of these travellers' diarrhea causes Can be controlled very well with the Zythromycin or a fluorocuenolone Right? Is it thromising or a fluorocuenolone Right? The one big exception we've talked about today Is a G-ardia, right? That we use metronidazole or tinnitus-ol-for Right? Make sure you know the bugs that are covered by metronidazole Right? There's this nice, the one you've probably heard Get gap on the metronidazole like G-ardia Intamiba histolidica That's the E, right? So get gap on the metronidazole Right? So G-ardia If we're in tamiba histolidica, the thing that causes amybiasis The T-for-trickomoniasis Right? And then the G-other G-for-gannerella vaginalis The A-for-aneroops and then the P-for-pronozones Right? Those are the drugs that are Those are the bugs that are covered by metronidazole All right?

And then the last thing I want to talk about Travelers diarrhea This is actually something they love to test And this is something that gets a lot of people Because people don't think about this As a potential cause of travelers diarrhea But think of Cryptosporidium Parvam Think of Cryptosporidium Parvam Think of Cryptosporidium Parvam Cryptosporidium Parvam And you're going to see after the discussion I have on Cryptosporidium Parvam Why they really love to test it a lot on the USMELIS The reason they love to test it a lot on the USMELIS Is that there are so many integrations you can make With Cryptosporidium Parvam for your exams Right? So many of us know the classic You see watery diarrhea in a HIV patient Cryptosporidium Parvam Right? And many times they will talk about the Acid Fast Oasis in the stool Remember Cryptosporidium is Acid Fast Is Acid Fast So if they tell you about a person that is immunocompromised And the person has Acid Fast Oasis in their stool Think of Cryptosporidium Parvam Okay? Think of Cryptosporidium Parvam And remember that Cryptosporidium Parvam Is treated with Naita Zoxanide Right? Should have the drug Naita Zoxanide Naita Zoxanide Now the thing is the friends at the NBM They know that everybody That has the job description medical student Or USMELIS exam taker has memorized Cryptosporidium causes Daryan HIV patients Right? So what do they do these days? They like to test it as a cause of Travellers Diarrhea Okay?

But is going to typically present as Travellers Diarrhea In an immunocompromised person Or it can prevent as Travellers Diarrhea In an immunocompetent person And then they will give you the stool results They will say that, oh wow This person is immunocompetent You know, the person doesn't have any HIV or immunodeficiency disease But you know, the person has diarrhea You know, profuse watery diarrhea And then they tell you that Oh, they do some testing of the stool And they find Acid Fast Oasis When you see that Then you want to think about Cryptosporidium Parvam Right? So if you see a Travellers Diarrhea context In a person that is immunocompetent And you see Acid Fast Oasis in the stool The person has Cryptosporidium Parvam infection Right? And again remember Cryptosporidium Parvam Right? It's an interesting little protozoan Right? It likes to infect your small intestinal epithelium Right? That's why it causes nasty, nasty, nasty diarrhea Okay? And the thing is, believe it or not People can also get Cryptosporidium Parvam From swimming in pools that are chlorine treated Right? Because the thing is chlorine does nothing To Cryptosporidium Parvam That's actually something that is pretty high To know for you exams A chlorine treated pool does not mean that Cryptosporidium Parvam Has been killed Right? So again, like I said It can present in immunocompetent people Or it can present in immunocompromised people Right?

In fact the thing is Most times when people are immunocompetent You don't have to treat them They don't need nitrous oxide Right? So think of nitrous oxide as something you do For a person that has C-parvam infection That is immunocompromised That is immunocompromised Okay? So the thing is If a person is immunocompetent And they have Cryptosporidial Diarrhea Self-limited You know within a week or two They're going to get better They're going to get better Right? And why do they get better? Well because they have functioning immune systems Let me tell you this Let me tell you this Let me tell you this Your CD4 positive T-cells Are extremely critical For dealing with Cryptosporidium Parvam I'm going to say that again Your CD4 positive T-cells Are extremely critical For dealing with Cryptosporidium Parvam infection Right? So if you're a person that has immunocompetent You have well-functioning CD4 positive T-cells You're going to clear that infection But if you're a person that has HIV Whoa Right? Your CD4 positive T-cells Have been nuked and destroyed Then in that circumstance You're probably going to struggle with this infection Right? So if you see a person that has like cholera Like diarrhea And they immunocompromised like a HIV patient Think of Cryptosporidium Parvam infection Many times It's going to show up as a nasty nasty infection And a person that has a very very low CD4 count Typically it's going to be a person that has a CD4 count That is under 200 Right?

So you're going to see it presents like just severe Chronic nasty diarrhea They can be popping more than 10 liters of fluid a day Right? Severe nasty chronic diarrhea Right? And they will have like Nasty malabsorption A lot of weak loss They will be like super dehydrated Right? And the thing is one strange association They love friends At the MBM is love to test with Cryptosporidium Parvam Is that he can spread to your biliary tract It can cause a sending cholangitis It can cause acute pancreatitis It can literally spread to your biliary tract It can literally spread to your biliary tract Right? So the thing you may be asking is Divine Why do they love to test it in people that have CD4s on that 200 Typically Again It can happen in people with CD4s over 200 But classically When they are testing a HIV patient that has Cryptosporidium Parvam infection Their CD4 count is usually going to be less than 200 Well Why is that? Because again The people that are more likely to get this Or people that have severely clobbered Severely clobbered CD4 positive T cell count Right? And hey If your CD4 positive T cell count is on the 200 You're going to have a severely clobbered count Right? That's going to make it very very difficult For you to be able to clear the infection Right?

In fact, let me tell you this Okay Whenever you see me laugh like this It's because it's like Yep, this is another thing they don't do on the USMT to people See On the exams They can give you a question about a person that has polycontrolled HIV Right? They'll tell you the person has not seen the physician in many years And then they describe this person in CD4 count as being like 60 And then they tell you that the person has had like profuse watery fast-millin diarrhea For the last few weeks Right? And then they say that Oh Stole study is positive for acid fastosis And then they ask which of the following Would most likely lead to long-term resolution of this patient symptoms Or most likely improve the patient's prognosis Pick the answer that talks about initiation of anti-retroviral therapy I'm going to say that again Pick the answer that talks about the initiation of anti-retroviral therapy The thing is if you put a person that has cryptosporidium problem infection If you put them on Night as oxanide Right? An immunocompromised person It will help their symptoms But they will not completely clear the infection That infection will stay persistent in those people For a very very long period of time If you want to truly clear cryptosporidium problem infection You need your CD4 positive T cells to come back online You literally need your CD4 positive T cells to come back online Okay?

So night as oxanide Again It can help It can help But you will not completely clear the infection Right? In fact again they can make this a prognosis question Again I was discussing this in one of the classes I thought last week You know I was thinking people that hey They love love love to test prognosis a lot On the US Emily exams these days Right? And what is one class equity love to test prognosis They love to test it in a context like this for example Right? In a context like this Right? You truly will improve a person's prognosis For cryptosporidium problem infection When you initiate anti-retroviral therapy In fact that is the most important intervention In properly clearing cryptosporidium problem infection You can give them night as oxanide But it's basically like a temporizing measure You want to permanently clear that problem Or I can boost the CD4 positive T cell count By giving them what anti-retroviral therapy Now one other angle that they love to test with Cryptosporidium problem infection on the exams Is that they also love to test it in the context of iris Right? So they will give you a question about a person that had a CD4 count of like 40 And then the person was initiated And the person had like you know very nasty you know weeks of like Watery diorama and all these things And then they ask you And the person has weeks of watery diorama Right? And then they tell you that oh pharmacotherapies initiated Or they can even make it a two-part question Right?

You know night as oxanide therapies initiated And the patient is also placed on anti-retroviral therapy Right? They can make that the first part of the question They can test things around those concepts for the first part of the question And then the second part they can say that you know One week after therapies initiated The patient presents with like worsening diarrhea You know very high fever Severely you know profound weight loss And profound dehydration And then they ask you which of the following is the most appropriate next best step in management I would really hope you are picking the answer choice That says to continue anti-retroviral therapy Continue like the oxanide And if necessary Go ahead and give them steroids So what's going on with this person? Well this person has something called iris This person has immune reconstitution Inflammatory syndrome Immune reconstitution inflammatory syndrome Our friends at the MBM is the love to test iris a lot And many times they love to test it In the context of cryptosporodium pervame infection Okay? Basically what is iris? Iris is basically like So immune reconstitution inflammatory syndrome Like literally look at the name Immune reconstitution inflammatory syndrome You are literally reconstituting the immune system And then you get an inflammatory syndrome from that Right?

So say for example how would this arise in a person that has cryptosporodium If you understand this model Then whatever any other model is going to make sense to you Right? But basically for a person who has Cryptosporodium problem infection They are immunocompromised They are like a HIV patient really bad HIV Right? When you start anti-retroviral therapy The CD4 positive T cell count is going to start rising Right? Now as that CD4 positive T cell count starts rising Your immune system begins to recover So your immune system that is recovering is going to be like I am going to search out every cryptosporodium that is in the body I am going to destroy them I'm literally going to destroy them So what does your immune system do? The thing your immune system does Is that it starts going after tissues that contain cryptosporodium in them Right? And that initial inflammatory cascade Because we find cryptosporodium problem in the GI tract That initial inflammatory cascade Guess what it does Is going to just absolutely destroy many parts of your GI tract So that can cause you to temporarily have a worsening diarrhea Right? So those people may have a temporary worsening of their diarrhea They may have a temporary worsening of their abdominal complaints But they will get better over time Just to make sure that the patient is healthy And that's the way to get better But they will get better over time Just tell them to stay the course Right?

So how do you manage immune reconstitution inflammatory syndrome? Literally Continue anti-retroviral therapy Literally Continue the night of Zoxanide Right? Although the person is immunocompetent You really don't have to do that night of Zoxanide Right? But for the immunocompromised person Night of Zoxanide Right? Give them night of Zoxanide Give them anti-retroviral therapy Right? Because again, remember Upregulation of their T-cell counties The most important intervention in controlling And in clearing crypto-sparadion problem infection But a third thing you should also do for those people is steroids Right? If it's really really bad Then consider giving them sterates Consider giving them sterates Okay? Consider giving them sterates Right? So again, these people see the four positive T-cells The T-helper-one cells They come back online Right? And remember your T-helper-one cells are involved with cell-meditated immunity So any cell that contains crypto-sparadial antigens They're going to start attacking them hard They're going to start attacking them hard They're going to literally start attacking them hard Start attacking them hard Right? But again, typically those people are going to get better over time Right? It's basically a transient inflammatory flare You know, I just like to think of it this way Right?

Like say for example If you have not eaten for a long period of time Unless you've been fasting for seven days The first time you see food You're going to eat that food very aggressively Second time you see food You're going to eat that food very aggressively Very violently But by the third plate of food The fourth plate of food You're going to kind of slow down a little bit Because now you've had food Right? Things are not as bad Right? So the thing is kind of like the same thing happens with Immunic constitution inflammatory syndrome Your immune system is coming back online Right? So it wants to kind of flex its muscles It wants to show that hey I'm back But after it kind of flexes its muscles Kind of cleans things up It then kind of goes back to it like normal baseline state Right? So again, if something want to keep at the back of your mind for your exams Okay? Something want to keep at the back of your mind for your exams All right And again, remember One other thing that may be used for travelers diarrhea before I'm kind of don't want travelers diarrhea Is don't forget Don't forget Travelers diarrhea One of the ways some people treated is with Bismuth sub-salicylate Bismuth sub-salicylate Right? Now if a person has a He's sort of like aspirin allergy Right? Or a person has a He's sort of like aspirin exasperate Aspirin exasperated respiratory disease Giving Bismuth sub-salicylate is maybe not a good idea Like literally contains Salicylic acid Right?

So if you have like an aspirin allergy And so we can have profound aspirin allergies Bismuth sub-salicylate is not a good idea Because again, remember Bismuth sub-salicylate basically contains aspirin It basically contains aspirin All right Now next thing I want to talk about here What if they give you a question about a patient Right? What if they give you a question about a patient And this patient, you're told that Ooh, this person you know Travel to some foreign country Right? And the person has like Extremely high fevers Very severe headache And that they have a retroorbidal pain They have pain behind the eyes Right? They have a lot of myalgyus A lot of astralgyus Right? And that this person to move their Arms or their knees or their legs The person you know Complains of 10 out of 10 severe pain When you see something And they have a rush on the skin Like a blanch in macular popular rush When you see something like this Please, please, please What should you be thinking about? Dengue, dengue, dengue Dengue, right? Think of dengue on your exams Think of dengue on your exams Right? And many times again These people are going to have PTK And proper on their skin And they actually have bleeding Right? In fact, there is a reason why it's Called dengue hemorrhagic fever Right? They can bleed

They can have a lot of plasma leakage And I'm going to discuss the pathophase here shortly Right? But they can have a lot of plasma leakage That leads them to have Um You know, they can have like shock You know, very severe bleeding You know, multi-organ dysfunctions Syndrome and things like that Right? And things like that Now, one thing our friends At the MV is love to do Is that they love to test a lot of Integrations with dengue They love to test a lot of Integrations with dengue So let's kind of talk through Dengue Okay? So first things first What's the bug that carries this? Well, I hope you're saying that Ooh, divine Is the 80s mosquito Right? The 80s A-Gipti mosquito The 80s A-E-D-E-S A-Gipti is A-E-G-Y-P-T-I The 80s A-Gipti mosquito Right? And again, typically In fact, like If you see a person that Travels to a tropical area And they have like very high Fever Very severe headache Very nasty muscle pain Especially like Retrobedo-ipane Petigui-Pepero on the skin Echimosis on the skin Right? Think of a person having Dengue hemorrhagic fever Right?

Dengue is actually the most Common abo viral disease Worldwide It's literally The most common abo viral disease Worldwide I think there's about 400 million infections That happen a year All right So What are some strange Immunology related things That are friends that the MV Is wanting to know About Dengue Again, Dengue is heavily tested guys Dengue is heavily tested Number one is that When you have a primary Dengue infection It's usually going to be a mild Infection It's usually going to be Mostly symptomatic However, When you have a secondary infection With a different serotype That infection can be life-threatening It can literally lead to death It can literally lead to death Okay? So again, let me break this down The first infection you have The primary infection Typically is not as bad As the secondary infection Right?

Many times if you get Dengue the first time You're going to have symptoms It's going to suck But it's not going to be as bad as If you have a different infection A second infection A secondary infection with a different serotype When you see something like this These people can have very severe symptoms And their mortality is much higher When you have a secondary infection With a different serotype With a different serotype So you may be asking like divine Why is it that the You know because I've learned in immunology That the first time you encounter an infection You know you have like a very severe symptoms But you know down the line in the future It's not as bad Why do things seem to be different with Dengue? Okay, let's break it down Right? And the thing is the mechanism here is something called The mechanism here is something called Antibody dependent enhancement Antibody dependent enhancement Our friends at the Indian Museum They love to test this on the exams And for whatever bizarre reason Many resources do not cover this But the fact that many resources do not cover something Does not mean that it is not very high to know for your test Okay, so let's break this down If you follow along with this You're going to be able to keep this in mind Right? So again What is this antibody dependent enhancement What the thing is Dengue has four serotypes Dengue literally has four serotypes There is DEMV1 DEMV2 DEMV3 and DEMV4 Right?

So the thing is When you have a primary infection Let's assume that The first infection you have is with DEMV1 Right? DEMV1 The thing that will happen is When your body sees DEMV1 Your immune system is going to make Anti-DEMV1 Antibodies D-E-N-V1 Your immune system is going to make Anti-DEMV1 antibodies These DEMV1 antibodies They're going to neutralize They're going to absolutely just neutralize The DEMV1 And you're going to feel good Right? You're going to feel good But one thing people don't realize is That these anti-DEMV1 antibodies They have some mild Cross-reactivity With a DEMV2 DEMV3 and DEMV4 So they cannot neutralize They can only neutralize DEMV1 They can only neutralize DEMV2 DEMV3 and DEMV4 They can cross-react with them But they cannot neutralize them Right? So let's say for example You then get a second A second episode of Dengue But this second episode You get it with DEMV2 Instead of DEMV1 I can promise you that this second infection That they have Is going to be much much much much worse Than the first infection they had In fact they can die From this secondary infection Right? So what's the pathophase here What's going on here Remember what I said I said Anti-DEMV1 antibodies neutralize DEMV1 But they can cross-react They cannot neutralize They can only cross-react with DEMV2 DEMV3 and DEMV4 Right? So these anti-DEMV1 antibodies What do they do?

If you have a A secondary infection with DEMV2 They will bind to DEMV2 They will literally bind to DEMV2 But they will not neutralize DEMV2 The unfortunate thing that actually happens here Is that they are actually going to quote the virus And facilitate the entry of the virus Into your immune system cells Whoa They are going to quote the virus And then facilitate the ability of the virus to enter Your immune system cells Wow Wow Right? Wow This is something you definitely need to understand for you Example So what's the mechanism here Well the thing is When these anti-DEMV1 antibodies Bind like DEMV2 for example Right? Remember every antibody has a constant region Right? When that constant region can be bound by a kind of receptor Called the FC Gamma receptor The FC Gamma receptor Is a receptor that we find on many immune system cells Like your natural killer cells Your macrophages Right? Sometimes it's called CV-16 Right? So we find it on natural killer cells We find it on monocytes We find it on macrophages We find it on the endritic cells Right?

And this FC Gamma receptor Can recognize the constant region of IgG So if you have anti-DEMV1 IgG antibodies that bind to DEMV2 Then the constant region of those anti-DEMV1 antibodies Will literally bind Will be bound Sorry Will be bound By the FC Gamma receptor And then when it's bound by the FC Gamma receptor That actually facilitates It almost provides like a highway For DEMV2 to infect your white blood cells Very very effectively To influence your white blood cells Very very efficiently Right? So when that happens When that happens DEMV2 Rakes hover on your white blood cells It basically gains a lot of entry Into many of your cells And that causes you to get in very very severe trouble Because remember Whenever your white blood cells get infected They start releasing all those nasty things That they have in the aluminum But what are those nasty things they release Or they release many of these acute phase reactants You know You know IL1, IL6, TNF alpha They can release things like interlooking 8 Right? And the thing is These things cause a lot of inflammation One of the things they do Is that they increase vascular permeability Right? They increase vascular permeability How by disrupting your tight junctions Right? By disrupting your tight junctions

Right? So if you increase vascular permeability By disrupting tight junctions Right? You're going to cause a lot of leakage of plasma From your blood vessels into tissue spaces Right? From your blood vessels into tissue spaces Right? That's what's going to cause people to start having all this Hammerage Right? Causing all these Hammerage And the thing is Because a lot of fluid is leaking from your blood stream Into your tissue spaces The hemoglobin that is left behind in your blood stream Becomes very concentrated So these people tend to be hemoconcentrated These people tend to be hemoconcentrated Okay? These people tend to be hemoconcentrated So this is why If we're giving you the dengue vaccine We want to make sure that it covers DEMV1 DEMV2 DEMV3 And DEMV4 Okay? So please on your exams If they give you a question about a person That has a second dengue infection And they develop like very severe disease Very nasty septic shock Very nasty hammerage And they ask you about the underlying mechanism Think about antibody dependent Think of antibody Think of antibody dependent enhancement Think of antibody dependent enhancement Again, the pre-existing antibodies You made to the first infection Right? They made the second infection worse Not better They literally made the second infection worse Not better They made the second infection worse Not better Okay? So again, remember How do we diagnose dengue on the USMEL exams?

Again, you can check the NS1 antigen right Or you can just check for antibodies IgM antibodies You can just do your antibody serologies Against dengue Right? You can also do PCR And again, the classic things you're going to see Lab-wise They're going to have low pleateless They're going to have thrombocytopenia They're going to have low copenia Their transaminesis are going to be elevated Right? Their LF Ts are going to be up Their ASTLT is going to be up Right? And they're going to have a high hematocrate Again, because of hemoconsentration Because of hemoconsentration Because of hemoconsentration Right? And how do we manage dengue? So body of care Right? IV fluids Right? No more saline Right? And please, please, please, please, please Right? What is one thing that gets people in trouble on the exams They're like, oh, divine It is dengue hemorrhagic fever So because they have fever I can give them aspirin or NSAI Ds No, don't do that Right? Literally look at the term that comes before the fever Hemorrhagic They are bleeding Why do you want to give things that can cause them to bleed some more Like aspirin or NSAID Right? They want to be a very smart idea in those people Right? They want to be a particularly smart idea in those people All right Now, what if they give you a question about a patient And they tell you that this patient You know, travel to some foreign country And the person has very, very high fever Right? And the person has jaundice Right?

And they give you You know, the person is extremely hypotensive And they notice that they have this element of acute kidney injury Right? And you also notice that they are pretty cardiac They are pretty cardiac And they even tell you that Oh, they have like three plus or four plus proteinuria If you see something like this What should you be thinking about? I hope you're thinking about yellow fever And typically they will give it to a person That is traveling to that travel That has traveled to sub-Saharan Africa In fact, let me tell you this This is why If you're traveling to sub-Saharan Africa Like Nigeria, for example, you know where I'm from You have to have had a history Of the yellow fever vaccine That's actually pretty high you to know for you exams Okay? If you're traveling to sub-Saharan Africa Like Nigeria That is actually one vaccine that is required Right? Say for example, you're an American in travel into Nigeria You better take that yellow fever vaccine Because yellow fever can kill Yellow fever can kill If you have severe yellow fever infection The mortality is about 50% It's actually pretty nasty Right? Okay, so keep that at the back of your mind for your exams So again, just to rehash What are the key things you want to know about Yellow fever for your exams? Again, how does it present? High-fever's Right? John Dis Right? And typically they'll have that John Dis with Breedy Cardia With Breedy Cardia Right?

And it also causes acute kidney injury It causes an AKI Right? So you notice a lot of protein in the proteins You're in You mean, you see a lot of protein in the proteins You're in And remember, this is carried by the Aedes Mosquito As well Right? Carried by the Aedes Mosquito And again, don't forget the sub-Saharan Africa Association Or the South American Association Especially within the Amazon Basin Right? And the thing is sometimes If they want to make this Question harder than it needs to be for your new exams Instead of putting yellow fever As the answer on your exams They can put flavy virus As the answer on your exams For sure, remember Yellow fever is a flavy virus infection And the thing is it has a very strong predilection for the liver It loves the liver It literally loves the liver So when it gets to your liver it infects your hepatocytes And causes necrosis of your hepatocytes And when you cause necrosis of your hepatocytes Guess what? Right? You're going to have Abumine problems Right? You're going to have Abumine problems You're going to have clotting factor problems Right? That's why they can have hemorrhage That's why they can bleed That's why their LF Ts go up Okay? So please keep that at the back of your mind for your exams Right? Keep that at the back of your mind for your exams Right? And how can we prevent this? Well, there's a live-attenuated vaccine There's a live-attenuated vaccine Again, these vaccines require for entry to many countries Right?

And the thing is once you get the vaccine Once, it's going to give you Life-long immunity It's literally going to give you one Life-long immunity Life-long immunity But again, remember If you're a little kid Under each one especially under each six months Know your yellow fever vaccine for you If you're pregnant Know your yellow fever vaccine for you If you're a minor compromiser Know your yellow fever vaccine for you Right? Or if you have like an egg allergy Know your yellow fever vaccine for you as well Right? Pretty high you'll to know that for your exams Right? Or if you have like de-George syndrome Or you have like um Skid Know your yellow fever vaccine for you Right? Whenever you have like absentein Like you have like an absentein thymus The yellow fever vaccine is not a good idea

Because that's a correlate with Nasty Nasty Nasty Immuno compromise Okay? Nasty Nasty Nasty Immuno compromise All right And generally for person Is over age 60 Yours won't be careful About giving them the yellow fever vaccine Because remember as you get older Your immunocompetence begins to wane Uh, quite a bit It begins to wane quite a Quite a bit All right Man, this podcast has gone on for longer than I planned Uh You know what? Let's maybe go ahead and pause here Let's go ahead and pause here I will do another travel medicine Again, like I said It's gonna be a tour three part series Gonna be a tour three part series again The thing is For my podcast I know people say like Oh, divine you then go off in this direction And then in this direction The thing is those integrations Will help you on your exams The USML is they don't That's the thing like this is probably one of the most common complaints I've heard with my podcast That if you divine your podcasts are not linear You keep going in different dimensions The reason I do that is because that will lead That's literally A much better way to prep for your exams It's uncomfortable But it's a better way to prep for your tests Right? My goal here is not to make you comfortable Because if I make you comfortable But I'm not prepping you well for your exams Then what was the benefit of spending 45 minutes or there about listening to me Right? It's better to deal with discomfort But it helps you prep well Right?

Growth happens in the midst of discomfort Right? You've probably heard this term I guess think of this as a life lesson That necessity is the mother of invention Right? So just gonna keep that at the back of your mind As you as you go through your life All right, so if you love the way I teach And again God willing I'm gonna We're gonna have another episode Episode 632 is gonna be travel medicine part Part two But if you love the way I teach you love the way I make integrations You're gonna love my classes Many people have taken my classes and done extremely well on the exams Right?

In this month of February Starting next week Monday I do have a series of classes For step one or the way to step three So what are my step one Or the way to step three classes Well, I have my test taking strategies class It's two and a half hours long I have my biostatistics class It's four hours long I have my social sciences and ethics And quality improvement And hospital medicine class That's five hours long Those classes are for step one or the way to step three But for step two and step three specifically I have a last mini review that is three hours long I have a 20 hours step two step three review that is You know, 20 hours long And then I have a class that is held only once a year It's in the month of June It's a 50 hour 500 multiple choice questions step two step three class I mean that class is phenomenal People that are taking the class Don't just extremely well on their exams So if you're interested in any of these classes I'm the one that teaches all of these classes In their entirety There's not like some TA That's teaching those classes No, it's literally me Overzoom that teaches the whole class If you're interested shoot me an email And I can give you some more information And then I also have this podcast On Apple Google and Spotify And also offer one on one tutoring I also help with applications Read like errors applications Mocking reviews personal statements Rec letters and things like that Right And then I have another website called Dividing Tro Ventional Life Lessons.com Dividing Tro Ventional Life Lessons.com Every week You know, you know, many of you are on a Christful hour I post like one or two podcasts From a biblical perspective Address a Life Lesson And there's actually an Apple Podcast Associated with that Called the Dividing Tro Ventional Life Lessons Podcast And then don't forget that I have a You Tube channel Where I also post the videos that I m

ake So thank you for listening to me in today's episode Again, I knew it was kind of a lot But again, there's so many exam questions You're going to get right from this stuff That are not even related to travel medicine So thank you for listening to me Have a wonderful rest of your day God bless your CNP's 1632 Bye for now

Two to four weeks before travel, to allow time for an adequate antibody response.

Yellow fever vaccine (or oral typhoid/MMR).

It is a 30 S ribosomal inhibitor, disrupting protein synthesis.

SADT (Sulfadiazine, Atovaquone, and Tetracycline).

Enterotoxigenic E. coli (ETEC).

Secretory diarrhea; heat-labile toxin activates cAMP/Protein Kinase A, causing massive chloride ion secretion into the lumen.

Giardiasis tends to be chronic (weeks) with malabsorption signs (steatorrhea), while ETEC is typically acute and secretory.

Aedes mosquito (specifically mentioned for Yellow Fever).

Thrombocytopenia, low platelets, plasma leakage leading to hemoconcentration (high hematocrit), and elevated transaminases.

Due to Antibody-Dependent Enhancement (ADE). Pre-existing antibodies from the first serotype bind to a second serotype but fail to neutralize it, instead facilitating viral entry into immune cells via the Fc Gamma receptor.

SADT (Sulfadiazine, Atovaquone, and Tetracycline).

Diarrhea lasting for weeks combined with signs of malabsorption/steatorrhea.

Hemolysis due to G6 PD deficiency, because primaquine is a powerful oxidizing agent that impairs glutathione regeneration.

Initiation of Anti-Retroviral Therapy (ART), as restoring CD4+ T-cell counts is necessary for immune clearance.

Liver tropism leading to hepatocyte necrosis, resulting in coagulopathy and elevated LF Ts/bleeding tendency.

Thrombocytopenia, low platelets, plasma leakage leading to hemoconcentration (high hematocrit), and elevated transaminases.

Due to Antibody-Dependent Enhancement (ADE). Pre-existing antibodies from the first serotype bind to a second serotype but fail to neutralize it, instead facilitating viral entry into immune cells via the Fc Gamma receptor.

SADT (Sulfadiazine, Atovaquone, and Tetracycline).

Diarrhea lasting for weeks combined with signs of malabsorption/steatorrhea.

Hemolysis due to G6 PD deficiency, because primaquine is a powerful oxidizing agent that impairs glutathione regeneration.

Initiation of Anti-Retroviral Therapy (ART), as restoring CD4+ T-cell counts is necessary for immune clearance.

Liver tropism leading to hepatocyte necrosis, resulting in coagulopathy and elevated LF Ts/bleeding tendency.