Chemical Meningitis, Leptomeningeal Carcinomatosis, Neurosyphilis, Lyme Disease

00:01 At this juncture once again, let me layout the plan for meningitis for you.

00:07 Overall, the topic in neuropathology that we are dealing with here is CNS infections and up until this point, really, all of everything we’ve done has been infections.

00:20 Now, this is a small topic but just to make sure we’re clear.

00:25 Chemical meningitis, obviously, this is not infectious, but it behaves like your traditional meningitis caused by infections.

00:33 Are we clear? So maybe iatrogenic, therefore, maybe myelography was being done resulting in a chemical meningitis.

00:41 Drug related, NSAIDS, your co-trimoxazole, penicillin, INH, and IVIG is an important one, isn’t it? In Kawasaki, your treatment of choice would be what management? IV immunoglobulin.

00:58 Could also result in possibly chemical meningitis.

01:03 Just to make sure that you're clear.

01:04 Say that your patient had an intracranial dermoid tumor.

01:08 What does the dermoid tumor mean to you? It’s one of those tumors that you’ve heard about before, in which instead of it being a deep type of fibromatosis, maybe perhaps missed tumor and there is rupture resulting in meningitis-type of symptoms.

01:26 You’ve heard of craniopharyngioma, something that you could find in a child and usually what you thinking about in this child? Complication you’re looking for is bitemporal hemianopsia.

01:37 Where are you? In the sella turcica, right? What does the sella mean to you? S-E-L-L-A.

01:45 It’s the home of your pituitary.

01:47 So when you say craniopharyngioma, your most common location and age, a child, in the sella in which it’s filled with -- We call it “crank oil" and therefore causing severe compression of the optic chiasm.

02:03 There is every possibility that there might be a craniopharyngioma cyst that will then rupture and when it does, it may result in meningitis-type symptoms.

02:13 Clear? Let’s move on.

02:15 Here, we have leptomeningeal carcinomatosis.

02:18 Once again, not infections.

02:20 Diffuse seeding of leptomeninges with metastatic tumor cells.

02:24 So say that your patient has glioblastoma multiforme, a severe type of astrocytoma, grade 4 and what may then happen? They might seed into the leptomeninges resulting in meningitis type of symptoms.

02:40 Symptoms include your headache, altered mental status, which you can expect with a meningitis type of picture.

02:48 and you can also have cranial neuropathies.

02:50 So what kind of cancers you might you be thinking about? Now apart from glioblastoma multiforme and seeding, what if there is metastasis from some of those other cancers that you are very comfortable with that might metastasize? And these include breast cancer, lung cancer, more so small cell lung cancer, your melanoma, medulloblastoma, think about the most common brain tumor in a child and your neuroendocrine tumors.

03:23 These may result in as soon as leptomeningeal carcinomatosis.

03:27 Allow the name to speak to you, it gives you meningitis type of symptoms, but these are not infections.

03:33 These are metastatic coming from other cancers.

03:38 Diagnosis: Imaging with MRI will then show you leptomeningeal enhancement and then obviously, you need to do cytopathology analysis of the cerebrospinal fluid.

03:49 Pretty straightforward in terms to diagnosis, but you must make sure that you keep in mind, if your patient has cancer and has meningitis type of issues, your answer choice would be leptomeningeal carcinomatosis.

04:03 We’ll come back to our infections again.

04:05 So with our infections, we’ll continue our discussion, but this time we'll have spirochetes.

04:10 So here once again, what I need you to do for me is keep your spirochete separate from mycobacteria, separate from bacterial.

04:18 Granted, spirochetes and mycobacterial are bacterial, correct? However, to make sense of what’s going on clinically, Keep the bacterial causes that we’ve talked about in great detail with age groups separate from tuberculous meningitis that we talked about in great detail and then quickly here, some of the spirochetal infections such as neurosyphilis.

04:39 We have borreliosis and leptospirosis.

04:43 Let’s talk about neurosyphilis.

04:44 So what happens here? Use your tertiary.

04:48 Neurosyphilis, what may happen? I close my eyes and I have lost my sense of proprioception, positive Romberg.

04:57 What else may happen? Lose your touch and vibration.

05:01 You’re referring to your tabes dorsalis.

05:04 So 15-40% of primary and secondary neurosyphilis patients have CSF abnormalities.

05:11 Very much could result in CNS infections.

05:15 Can present with dementia only.

05:18 Can also present with meningitis symptoms with variable focal findings based on what part of the brain has been affected.

05:28 Something that you’ve talked about earlier is Argyle-Robertson Pupil.

05:33 What happens here? So here, my topic is neurosyphilis.

05:36 Apart from tabes dorsalis which is of the spinal cord, dorsal column.

05:41 Where are you now? Unfortunately, the neurosyphilis has migrated up into the cranial cavity and therefore resulting in a whole host of other issues.

05:51 So what’s Argyle-Robertson Pupil? There is no direct or consensual light response, but pupils will constrict with accommodation.

06:00 Make sure you know the full definition of Argyle-Robertson Pupil, please, for neurosyphilis.

06:06 Or you could have a facial nerve or the vestibulocochlear or the most frequent affected cranial nerves.

06:13 What does that mean to you? Well, you might have difficulty with hearing or balance, vestibulocochlear or facial.

06:21 Maybe issues with the mouth and such, right? Neurosyphilis, you already know what happens in great detail with microbiology and tabes dorsalis.

06:30 Here, I’m walking you through more details that you need to make sure that you’re familiar with in terms of complications.

06:37 Diagnosis: CSF, but this time what you are going to find? Elevated protein with evidence of your? What is the name of the organism that causes syphilis? Treponema pallidum.

06:50 So what does this mean to you? Non-treponemal antigen test, RPR or VDRL and treponemal antigen test and this refers to FTA-ABS, fluorescent treponemal antibody absorption test.

07:06 Things that you’ve already talked about in micro, all I’m doing here is making sure that I reinforce it.

07:12 Treatment: Penicillin G for about 2 weeks or so.

07:18 Only of the few indications for desensitization if penicillin allergy exists, one of the few indications for desensitization.

07:27 Coexisting HIV infection can change recommendation of your management altogether.

07:33 So when we start getting into our HIV associated CNS infections, HIV changes the ball game altogether.

07:43 Continue our discussion with spirochetal type of meningitis.

07:48 Here, we have Lyme disease.

07:50 So what does Lyme disease mean to you? You begin with your patient up in New England.

07:56 So here we are in Northeast part of the U.S.

08:01 And what do you with your friends? So maybe you’re going out and you’re hunting.

08:06 You’re hunting for what? Well, maybe a deer.

08:08 You've heard of the deer tick and of course, this brings us to our Ixodes.

08:12 And the organism, the spirochetes specifically is the Borrelia burgdorferi and you’ve heard of your target lesion.

08:19 What is this called? Erythema chronicum migrans.

08:23 Are we clear about all that from micro? What may happen as complications years down the road? You could have arthritis, right? Arthritis, don’t forget that in rheumatology.

08:35 And the Lyme disease eventually could also cause issues in the brain.

08:39 We know about our Ixodes, erythema migrans.

08:43 What does that mean to you? Target lesion.

08:46 You know what a target looks like.

08:47 A central area of erythema surrounded by pallor with a peripheral ring of erythema.

08:53 Now, our focus will be on neurologic symptoms.

08:57 Aseptic meningitis.

09:00 Correct.

09:01 Granted it’s bacterial but unfortunately we have to call this aseptic.

09:08 "But, Dr. Raj, it’s a bacteria." It’s an infection.

09:12 Tell me that it’s an infection, but you’re calling aseptic.

09:15 Correct.

09:16 How many times have you heard of aseptic already? We know for a fact that it’s an infection.

09:20 For example, earlier, we talked about some of your aseptic, the type of valvular heart diseases or vegetations or in other words, I’m referring to what as known as valvulopathies.

09:33 Sometimes it is called aseptic, but you know for a fact that there is organism such as HACEK.

09:39 Right? Or what about prostatitis.

09:43 There is every possibility that could be aseptic but it is still could be caused by infection.

09:48 So keep that in mind.

09:49 Facial nerve palsies is a huge one from neuroanatomy.

09:54 Mild encephalopathy.

09:56 Remember, any part of the brain could be affected, both the parenchyma.

09:59 And polyneuropathies, number of cranial nerves could be affected.

10:03 Keep these in mind.

10:05 Our topic is Lyme disease, but specifically causing infection in the brain.

10:09 Treatment here, amoxicillin or doxycycline or IV ceftriaxone can be used if symptoms are quite severe.