Herpes Simplex Encephalitis: HSV-1 and HSV-2

by Carlo Raj, MD

Questions about the lecture
My Notes
  • Required.
Save Cancel
    Learning Material 2
    • PDF
      Slides 10 CNSInfections Neuropathology I.pdf
    • PDF
      Download Lecture Overview
    Report mistake

    00:01 Our topic is herpes simplex encephalitis.

    00:03 But here, we’re dealing with HSV-1.

    00:06 What we’ll do here is divide HSV-1 and HSV-2 and then, I will highlight to you what parts of the brain are being affected with either type of viral infection.

    00:19 This must be black and white for you.

    00:20 Otherwise, a clinical presentation on your boards or in clinical practice is going to be difficult and if you miss it, I am going to be very upset.

    00:30 Most commonly in children, young adult.

    00:32 That’s why I’ll be upset.

    00:33 Most common in children, in young adults.

    00:36 What parts of the brain will be affected? You should know that it’s the frontal and temporal lobe.

    00:42 As soon as you hear about frontal lobe, then what kind of issues or what kind of activity are you thinking about? M and M.

    00:49 Mood and memory.

    00:52 Seizures could also be a possibility because we have encephalitis, which then behaves as a space-occupying lesion.

    01:01 Now, HSV-1 in terms of pathology, once again, please make sure that you’re familiar with what parts of the brain? The temporal and frontal.

    01:09 You focus on that.

    01:10 Here, the brain is undergoing such extensive damage, that we have necrotization and we have often hemorrhagic, dangerous.

    01:19 As soon as you hear about HSV-1 or herpes in general, you should be thinking about Tzanck and then what kind of inclusion bodies? Cowdry.

    01:28 And in the CSF, you should be thinking about PCR, polymerase chain reaction, as being the most accurate diagnostic procedure.

    01:37 This is HSV-1.

    01:40 Now, with HSV-1, we have a child that’s being affected.

    01:44 Do not waste time.

    01:45 You get a history and you suspect there is mood and memory and such that’s taking place.

    01:51 And now, at this point, treatment.

    01:52 You begin IV acyclovir as soon as possible.

    01:57 Do not waste time in a child because the brain is still developing.

    02:02 This is HSV-1.

    02:04 We’re going to move on to HSV-2 where the presentation is a little bit different.

    02:09 With HSV-2, this is then referred to as being your herpetic, viral meningitis Granted, you also call this with HSV-1, but HSV-2 is more genital in region, isn’t it? Generalized, what does that mean to you? Let me make that I emphasize this.

    02:27 If it’s HSV-1, you should be thinking about the frontal and temporal lobe that’s commonly affected.

    02:33 If it’s HSV-2, then generalized encephalitis.

    02:37 And usually, much more severe.

    02:39 50% of neonates born by vaginal delivery to women with active primary HSV, and genital infections.

    02:46 As soon as you hear about HSV-2, you should be thinking about that all common herpes and one in five individuals have herpes, so extremely common.

    03:00 And this is one of the TORCHs, isn’t it? Vertical transmission.

    03:04 And if you imagine, a baby, a newborn that is born with HSV-2 type of encephalitis, severe.

    03:12 In AIDS patients, HSV-2 may cause an acute hemorrhagic necrotizing type of encephalitis.

    03:19 Dangerous.

    03:20 Here’s a table once again on CSF findings, guess what are we focusing upon this time? Obviously HSV encephalitis.

    03:28 The WBCs here will be elevated, primarily lymphocytes.

    03:32 Neutrophils wouldn’t be much elevated.

    03:35 Your RBCs would be found, and that’s important, remember? Because brain parenchyma.

    03:41 And we have glucose, well, a little bit higher, and protein, but your focus should be on RBCs and with the specifics that we walked through with HSV-1, what parts of the brain? what parts of the brain? Temporal and frontal.

    03:56 If it’s HSV-2, it’s called herpetic type of encephalitis.

    04:03 And we call it herpetic because if it’s 50% of your newborns who have – who were born to a mother that has a primary HSV infection, that newborn, the brain may be completely necrotized, generalized severe.

    04:19 AIDS patient, AIDS patient, there is no age group.

    04:23 As soon as you have a patient who is severely immunocompromised, who then contrives HSV-2, what happens? Acute hemorrhagic necrotizing type of encephalitis, could I be any more dramatic about HSV? Here, we have another type of viral encephalitis, but this is called progressive, multifocal leukoencephalopathy.

    04:46 And as soon as you here about PML, by reflex, you should be thinking about J-C, J-C-, JC virus.

    04:53 And in pharmacology, there are certain drugs that could be then given in which your patient is predisposed to JC virus and make sure you’re quite familiar with those drugs in which the patient, amazingly, is susceptible to leukoencephalopathy.

    05:12 What does that mean to you? What does leuko mean? White.

    05:16 What does encephalopathy mean? Damage to the brain parenchyma, multifocal.

    05:21 So if there’s destruction of your white matter, if you take a look at this imaging study, you see the areas that are opaquish or whitish? Those are the areas in which the brain parenchyma is undergoing demyelination.

    05:38 Look at this.

    05:40 I said demyelination.

    05:42 Soon as your myelin in your CNS, you tell me, what kind of cells? Good.

    05:47 Oligodendrocytes, right? So now we have virus preferentially.

    05:52 Unbelievably, this virus will then prefer the oligodendrocytes, resulting in what? Leukoencephalopathy.

    06:01 Demyelination occurs in immunocompromised patients and also think about those drugs and PML, does not enhance on MRI as opposed to CNS lymphomas and toxoplasmosis.

    06:13 And those regions, we have absolute enhancement.

    06:17 Here, with brain damage, you’re going to find more of your leukoencephalopathic type of findings.

    06:27 VZV.

    06:28 When would you find this perhaps? Causing damage or infection of the brain or reactivation? And what’s reactivation? You should be thinking about a patient that’s immunocompromised.

    06:39 Older and, of course, this then brings you to your topic of shingles.

    06:43 But there’s every possibility that a brain infection may take place.

    06:47 We have persistent post-herpetic neuralgia syndrome in up to 10% of patients, be careful with this.

    06:54 We say post-herpetic because what is varicella zoster? It’s herpes family isn’t it? Also associated with what’s known as a granulomatous arteritis.

    07:06 It may cause an acute encephalitis with numerous sharply circumscribed lesions characterized by early demyelination.

    07:17 Inclusion bodies can be found in the glia and neurons.

    07:21 Here, for the most part, think of reactivation, please, with varicella zoster virus and please don’t forget about the post-herpetic neuralgia syndrome in up to 10% of your patients.

    About the Lecture

    The lecture Herpes Simplex Encephalitis: HSV-1 and HSV-2 by Carlo Raj, MD is from the course CNS Infection—Clinical Neurology. It contains the following chapters:

    • Encephalitis
    • Herpes Simplex Encephalitis: HSV-1
    • Herpes Simplex Encephalitis: HSV-2
    • Acute Viral Meningitis: CSF Findings
    • Progressive Multifocal Leukoencephalopathy
    • Varicella Zoster Virus (Herpes Zoster)

    Included Quiz Questions

    1. 15 years to 35 years
    2. Less than 1 month old
    3. Between 1 month to 2 years
    4. Between 40 years to 60 years
    5. More than 60 years old
    1. Middle temporal gyrus of temporal lobe
    2. Orbital gyrus of frontal lobe
    3. Angular gyrus of parietal lobe
    4. Lateral occipital gyrus of occipital lobe
    5. Pituitary gland
    1. Cowdry Type A Bodies
    2. Negri bodies
    3. Molluscum bodies
    4. Henderson Patterson bodies
    5. Cowdry Type B Bodies
    1. CSF HSV PCR
    2. CSF cell counts
    3. CSF protein
    4. CSF glucose
    5. Clinical diagnosis
    1. HSV-2
    2. HSV-1
    3. St. Louis virus
    4. Neisseria meningitidis
    5. Borrelia burgdorferi
    1. Oligodendrocytes
    2. Microglia
    3. Astrocytes
    4. Ependymal cells
    5. Peripheral nerve cells
    1. Herpes zoster
    2. Herpes simplex virus type 1
    3. Herpes simplex virus type 2
    4. Borrelia Burgdorferi
    5. St. Louis virus

    Author of lecture Herpes Simplex Encephalitis: HSV-1 and HSV-2

     Carlo Raj, MD

    Carlo Raj, MD

    Customer reviews

    5,0 of 5 stars
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1  Star