130 Encephalitis Review for the PANCE

Hello and welcome to the Physician Assistant Exam Review Podcast. My name is Brian Wallace. I’m the host and creator here. Today, episode 130, we’re going to be covering infectious neurological disorders, so encephalitis and meningitis. And we’re going to go through those in some detail and help us sort of get a better understanding here and understand exactly how the questions are going to come, what it’s going to look like. I’ve been having a lot of fun with the companion episodes where we dive deeper into that stuff. And today we cover more of the generalized content, try to paint the picture for you so that you have a good idea of what’s going on.

One of the things I always try to do in this podcast, in this show, is to not just teach the content but to demonstrate to you ways of learning it, to demonstrate to you ways of seeing what to expect on your exams so that when you get there, it’s not a surprise. Or when you’re studying, you’re not overwhelmed but you can start to see through the material and start to see what needs to be studied more, what you’re going to need to go into more depth on. And I get as a student, your first pass through all this stuff, it’s hard to recognize what’s important, what’s unimportant, and how to do all that. But that’s one of the things we really try to do here. So with that longer introduction, let’s go ahead and get started. My goal here is 100% to turn you into the best possible student, the best possible test taker that you can be. That’s really what my goal is.

So, every time we do something, every time we get involved in anything here, that’s what I’m having an eye towards doing. Just so you know my perspective. I want to get you to get as much as you can out of school. I want to get you through school. I want to get you through your clinicals, through your end of rotation exams, end of curriculum exams, through your PANCE, and then ultimately to get a job. That’s really the goal here. And that’s my goal for you, to have an impact on you throughout that entire period.

Now, speaking of impact on you, today is the 15th, right? So we are 15 days into the April cohort of the 33 Days to Pass the PANCE program. And the students are doing amazing things and they’re getting a ton out of it. Here’s why I bring that up. I’m already getting emails from students about the June cohort saying, when can I sign up? When is that going to be? I’m struggling in school.

One individual just said that they paused his clinical rotations so that he or she, I’m not even sure, can take some time and get kind of caught up. So they were wondering when the next cohort’s going to be. I have someone else who just failed their PANCE. So there’s everyone in all different areas. If you’re struggling in school, if you’re struggling with the PANCE, if you know someone who is, you know, one person just reached out to me. It’s been a year since they took their last attempt at the PANCE. That’s something I hate to see happen because we can make it so much better.

So anyway, the June cohort is not open for registration just yet, but I do have, I guess, what you’d call like a waiting list for that. You can go to physicianassistantexamreview.com/33June. So it’s just /33June and that will take you to where you can get notified as soon as registration opens and that’ll be available to you there. So, if you, again, if you’re someone who’s could use some improvement in your skills and improvement in your approaches, if you’re struggling, if you’re finding things to be just harder than they should be, if you’re someone who is falling behind or feels uncomfortable or you’re run down and not sure how to getting the scores that you want, definitely go check that out. physicianassistantexamreview.com/33June.

All right. Today, we’re going to be covering encephalitis and meningitis. So, let’s go ahead and jump into our priming questions. Which viral cause of encephalitis typically shows temporal lobe enhancement on MRI? Which viral cause of encephalitis typically shows temporal lobe enhancement on MRI? What’s the first-line treatment for suspected HSV encephalitis even before the lab’s return? What’s the first-line treatment for suspected HSV encephalitis even before the lab’s return?

Which type of encephalitis often presents with flaccid paralysis and is mosquito-borne? He had two clues in there. Which type of encephalitis often presents with flaccid paralysis and is mosquito-borne? What CSF findings suggest viral versus bacterial meningitis? What CSF findings suggest viral versus bacterial meningitis? What empiric antibiotics are started for suspected bacterial meningitis in adults? What empiric antibiotics are started for suspected bacterial meningitis in adults?

All right, all right, so let’s get started. So number one is, what is encephalitis, right? What is encephalitis? Well, encephalitis is inflammation of the brain parenchyma, often in a viral origin, presents with altered mental status, seizures, and focal neurological deficits. This can be life threatening. So for me, I’m holding on to inflammation of the brain. Most common cause, most common encephalitis is a viral encephalitis.

And that most common version of that is an HSV-1 encephalitis. So here we get a temporal lobe involvement in the MRI. That’s something that’s important to note. This may cause personality changes, hallucinations. There’s a rapid progression and a high mortality rate if left untreated. Your presentation here is going to be fever, headaches, altered mental status, aphasias, hemiparesis, so focal neurological signs, seizures, again, behavioral changes, hallucinations, photophobia, nausea, vomiting. Labs and imaging here is going to be cerebral spinal fluid.

You’re going to look for lymphocytic pleocytosis, elevated protein, normal glucose. Some of these are going to be hard to remember. You’re not going to remember when I say something like elevated protein, normal glucose for HSV-1 encephalitis. If you’re reviewing this, that’s helpful. If you’re hearing it for the first time, you’re never going to hold on to that. So I strongly recommend you go over to the website and read through the notes as you’re listening to this or maybe later on. You can find this episode at physicianassistantexamreview.com/130, just the numbers 130.

And look over the notes as you’re doing this and maybe make your own notes out of it and your own cards and your own ways to remember. Because me saying it is just, it’s just not going to be that sticky in this case.

Now, as opposed to PCR for HSV in CSF, look at that. Equals is the gold standard for diagnosis. That’s how you’re going to diagnose this. You’re going to PCR for the herpes simplex virus in the cerebral spinal fluid. You’re also, you also may get with all of these symptoms an MRI to try to figure out what’s going on. And that temporal lobe involvement, those hyperintensities in the temporal lobe are going to be a dead giveaway for HSV-1 encephalitis. Again, you may be thinking, like, why would I get a spinal tap and an MRI and an EEG and do all of these things?

And the answer is because you have to picture, like, the patient’s walking into the ER with altered mental status and hallucinations and seizures and focal neurological signs, and you’re trying to figure out what’s going on. So the EEG here may show periodic sharp waves or temporal, over temporal regions. Treatment is going to be IV acyclovir, A, as soon as possible. Do not wait for the PCR confirmation. The PCR is the gold standard for diagnosis, yes. But start acyclovir. Why not?

Start acyclovir right away. And then supportive care and seizure management.

Next, you have arboviral encephalitis. This is going to include all of the things like West Nile, Eastern equine, Western equine, St. Louis. Those are all arboviral encephalitis. These are generally mosquito-borne, so that means that they’re going to be in the summer and the fall. And they can be in specific areas of the country, right? I actually remember when West Nile was just coming in, I think when I looked it up, it was 1999.

I was actually in New York at that time. I graduated my undergrad in New York in 96. So I was still working in New York when this became a thing. And it was all over the news. And it was just in that area. But now it’s actually all over the country. So some of that’s useful information.

And some of it’s just for coloring in the pictures. Clinical presentation here is going to be similar to a herpes simplex virus, so it’s going to be fever, seizures, but then you’re also going to get things like tremors or myoclonus. And then the other one, especially in West Nile, is the flaccid paralysis. That’s a big one, right? Because that also scares the hell out of people. So, that’s a good one to put into a question. Flaccid paralysis would be arbo, arbo, I’m having trouble with that word, arboviral encephalitis, but especially that West Nile.

This may progress slowly, and it may come and go. For a diagnosis, you’re going to be looking for IgM in the bloodstream or in the cerebral spinal fluid. The cerebral spinal fluid may have hyal lymphocytic pleocytosis and elevated proteins. The MRI tends to be nonspecific. Treatment. Here there’s no antivirals given. It’s only supportive care.

So supportive care, supportive care. And then prevention. So we’re going to try to avoid mosquitoes. Great. So that was encephalitis. Pretty straightforward. Symptoms are pretty similar.

The things you’ll have to separate out here are going to be discovering if it’s HSV-1 so you can do acyclovir or if it’s something like a West Nile, in which case you’re just going to do supportive care. To me, just reading through this over again now as I’m going through it is that flaccid paralysis is something I’d really pay attention to. The IgM versus the PCR is something I’d really pay attention to. The symptoms are going to be kind of similar, so it’s going to be hard to tell. The MRI results might be something to pay attention to. That temporal lobe involvement for HSV-1.

All right, how about meningitis? So for meningitis, we have a couple of different categories. We have acute bacterial meningitis. We have viral meningitis. We’re going to cover tuberculous meningitis.

All right, so let’s start with acute bacterial meningitis. This is the most serious and rapidly progressing form. This can be strep pneumonia, Neisseria meningitidis. Those are the most common in adults. In neonates, you’re looking at group B strep, E. Coli, and Listeria. I would probably hold on to those.

That seems like it could be an easy thing to write a question on. What’s the clinical presentation look like for acute bacterial meningitis? So, to me, this is one of those that you probably already know, right? So, memorizing this list, not so helpful. Thinking it through, more helpful. At least it would be for me. So, if I have an acute bacterial infection, a fever makes sense, headache makes sense, the nuchal rigidity thing is something that just seems to stick with people.

So that’s one that should be pretty easy to remember. Photophobia, altered mental status. The petechial rash, that might be something to pay attention to because to me, if I’m writing a question or I’m looking at a question that’s on acute bacterial meningitis, it’s not that petechial rash is going to be the only symptom, right? They’re not going to be like, oh, I came in with a headache and a rash and it’s going to be bacterial meningitis. That seems pretty unlikely. Is it possible? Sure, it’s possible, but very unlikely.

More likely is that’s going to be a key term or a little breadcrumb that’s going to turn up in the question, and it’s going to throw you off if you don’t know it. It’s actually just going to help you to be sure they’re talking about acute bacterial meningitis, but if you don’t recognize it, you’re going to see that rash and be like, oh man, maybe I’m heading the wrong direction. I thought it was bacterial meningitis, but now I’m not so sure. So I would make sure I knew that one for that reason. And it’s not going to be the only thing you see, but it will help to confirm it as you’re reading through your questions. Negative seizures or cranial nerve palsies. So how are we going to diagnose this?

Well, we’re going to get a spinal tap. We’re going to look for elevated opening pressure, elevated proteins, decreased glucose, and then a predominantly neutrophilic pleocytosis. Diagnosis is going to be blood cultures and a lumbar puncture. CT of the head first of signs of increased intracranial pressure. So papilledema, focal deficits. And we do a gram stain and culture of the cerebral spinal fluid, right? Right out of the gate, empiric treatment, we’re going to do ceftriaxone and vancomycin.

And we can do dexamethasone with that first antibiotic to reduce neurological complications.

Next, we have viral meningitis or what’s sometimes called aseptic meningitis. This is often self-limiting. And enteroviruses are the most common, but you can get Coxsackie, echovirus, those kinds of things. HSV-2, varicella, HIV are all possible causes here, but less common.

Now, here’s the real problem. What’s the clinical presentation for viral meningitis? Well, it’s fever, headache, nuchal rigidity, which may be more mild than in bacterial, but it’s still there. Photophobia, mental status changes. So it kind of looks the same, right? At least as I’m reading through these, I don’t treat patients in this realm, so it’s hard for me to say. Maybe there’s some subtle differences, but that list looks very much the same.

So if I’m a student learning this, I’m looking at it saying, okay, the clinical presentation for meningitis, whether it’s a viral or a bacterial, is very, very similar. So, how are they going to ask me to separate this? They’re not going to ask me to do it through clinical presentation. They’re going to ask me to do it on the cerebral spinal fluid. They’re going to ask me to do it on the exams. They’re going to ask me how do I treat it, that kind of thing. So, for the cerebral spinal fluid findings, you get normal or mildly elevated opening pressures.

You get normal or mildly mildly elevated proteins, normal glucose. So, you can see that we have a difference here. Treatment is here is going to be supportive care, although consider acyclovir for a suspected herpes simplex virus or varicella. But again, largely, it’s going to be supportive care.

Next, we have fungal meningitis. Where do we see fungal meningitis? What patient population? This is generally in the immunocompromised patients, especially HIV or AIDS. Cryptococcus neoformans is the most common.

All right. So, for our clinical presentation, it’s slightly different. There’s a subacute onset. That may be the key. Subacute onset. Headaches, fevers, malaise, cranial nerve deficits. Cerebral spinal fluid, you get elevated opening pressure, lymphocytic pleocytosis, low glucose, elevated protein.

Again, head back over to the website. Check out physicianassistantexamreview.com/130 to get the notes so you can see what I’m talking about. It’ll stick a whole lot better. Diagnosis, India ink stain, right? Do you remember that? Cryptococcal antigen and a fungal culture. Treatment.

This is something I actually do remember from PA school, amphotericin B.

Now, in this case, they’re going to up that to amphotericin amphotericin B plus flucytosine, then fluconazole for maintenance over time.

Next, we’re going to look at TB meningitis. This is a reaction of latent TB, especially in high risk or immunocompromised patients. So, again, when you’re looking at test questions, right, you should be thinking about the type of people that are going to come in with these things. There’s a reason they give you the demographics because it helps to narrow down everything so much. So, if I have an immunocompromised person come in with cranial nerve deficits, altered mental status. Now I’m thinking I have an infectious encephalitis, but it’s going to point me towards TB meningitis or fungal meningitis. Again, is that always the case?

Absolutely not. Those patients are just as much at risk for bacterial and viral, but in your test questions, it seems much more likely that they wouldn’t do that to you, right? So, clinical presentation, gradual onset, again, fever, night sweats, weight loss, cranial nerve deficits. CSF findings, very high protein, very low glucose. Lymphocytic pleocytosis may require large volume CSF sample for AFB stain cultures. MRI with basilar meningeal enhancements. Treatment is going to be your RIPE therapy plus steroids.

So that’s rifampin, isoniazid, pyrazinamide, and ethambutol, right? Your standard treatment for TB. I’m not going to go down the road and talk about those. There’s obviously some side effects and things that you should know and the different criteria and how long you do it and all that, but that’s not really for this particular section. We’re not going to go dive deep into that here.

All right, fantastic. So that will wrap us up with infectious neurological disorders. We covered meningitis, we covered encephalitis, and I think you’re in a good position to get these right.

So let’s stop and take a look at, oh, before I give you the answer to our priming questions, I do want to do our study tip for today. Our study tip for today is kind of what we’ve been talking about throughout and something we spent a lot of time in last night’s coaching meeting for the 33 Days program with the April cohort, which is the idea of staying out of the weeds and the idea that you only have so much time to study. You only have so much space in your head. You only have so much focus. And then for most PA schools and most students, the next quiz is the next day. The next test is the following day. Two tests the day after that.

You don’t have the time, right? If you had time, maybe you could handle all the information, but you don’t have the time. So what do you do? Well, there’s a lot of different things you could do, right? But one of the things you do is you do what we did in this particular episode, is we look for what’s testable. We look for what differentiates different diseases. We look for how to pull the things apart and look for the things that we have to know and try to let go of the things that are, I’m going to say, less important in this setting.

I hate to say less important because I know you feel like and everything is kind of important in its own way. But certain things are less important as it comes to your exams. It’s just the way it works. So one thing is to make some decisions about what to focus on, what to spend extra time on, what to cut back on. That goes for whole topics. It goes for different diseases. It goes for different medications.

But it also goes for the information within those topics, within those diseases, within those labs. It’s hard to tell what’s important, what’s not important, but that’s the skill you need to be sharpening right now. And one of the things I’m trying to teach you throughout these episodes is how to pull out the most important information and then study that. So people say, how do I do this? It takes too much time. And the answer is you cut down on what you’re studying and you focus on what’s important. Anyway, we could spend a lot of time on that, but that’s, I’m hoping that as you listen to these episodes, you’re starting to see that more and more.

All right, let’s get into our priming questions. Which viral cause of encephalitis typically shows temporal lobe enhancement on MRI? Which viral cause of encephalitis typically shows temporal lobe enhancement on MRI? HSV-1. What’s the first-line treatment for suspected HSV encephalitis even before the labs return? IV acyclovir. So the way this was worded, hopefully you were able to get it, but regardless, IV acyclovir.

Which type of encephalitis often presents with flaccid paralysis and is mosquito-borne? Arbo, arbo. Man, this is, we’re almost done here and I still screwed it up. Arboviral encephalitis, most commonly West Nile virus. What CSF finding suggests viral versus bacterial meningitis? Viral is normal glucose, normal to slightly elevated protein, and lymphocytic predominance. Bacterial is low glucose, high protein, neutrophilic predominance.

What empiric antibiotics are started for suspected bacterial meningitis in adults? What empiric antibiotics are started for suspected bacterial meningitis in adults? Ceftriaxone plus vancomycin. Hey, that was fantastic. Really not a terribly difficult topic, but something that does take some work to wrap your brain around to start to separate out those diseases, start to see how those patients would walk through the door. Mentally think about what you would be doing, how you’d order the MRI, how they would look with those mental status changes, with paralysis, with whatever else they have going on, and think about, man, I probably would order a lumbar puncture. I probably would order a head MRI or CT or something to try to figure out what’s happening and then walk through that process in your head.

Creating those little stories is another really good way to help solidify this stuff and stop memorizing those lists. If you’re interested in learning more, improving your skills, and June would be a good time for you to do that, definitely go over to physicianassistantexamreview.com/33June and get signed up for the pre-notification list and I’ll let you know as soon as registration opens, which will be the middle of May. Somewhere around the 15th ish, I got to look at the calendar and see exactly when that’s going to be. But that would be how to find out first about registration. So all right. Great to talk to you this week. This was an absolute ton of fun for me.

I’m looking forward to next week when we do those companion episodes and we walk through some actual questions and how to make this stick even more.

All right. Take care. Have a great week. And I look forward to talking to you again next week. Thank you.