| Identifier |
toxic_optic_neuropathycat_mudpiles |
| Title |
Toxic Optic Neuropathy CAT MUDPILES |
| Creator |
Andrew G. Lee, MD; Bryan Luu |
| Affiliation |
(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (BL) Class of 2022, Baylor College of Medicine, Houston, Texas |
| Subject |
Metabolic; Acidosis; Toxicity |
| Description |
Summary: Neuro-ophthalmic manifestations of anion-gap metabolic acidosis • CATMUDPILES o Carbon Monoxide -Anoxic encephalopathy and cortical vision loss o Aminoglycosides -Dizziness and imbalance -Oscillopsia from nystagmus -Disruption of vestibulo-ocular reflex (VOR) o Toluene -Demyelination in the cortex -Often presents as a cortically blind kid o Methanol -Bilateral simultaneous loss of vision o Uremia -Uremic optic neuropathy o Diabetic Ketoacidosis -Orbital apex syndrome -Mucormycosis due to ketoacidosis o Propylene glycol o Isoniazid -Treatment for tuberculosis -Bilateral slowly progressive central scotoma from a retrobulbar optic neuropathy o Lactate -Commonly seen in mitochondrial disorders -Stroke-like episodes o Ethylene glycol -Similar to methanol o Salicylate |
| Transcript |
So today we're going to be talking about CATMUDPILES. If you're wondering what CATMUDPILES is, it is the differential diagnosis that we are looking for when we have an anion gap metabolic acidosis. As you know, the anions can account for the acid-base balance. But if we have a gap between those anions, then we know something is in your blood that is accounting for that anion gap that's not your typical electrolyte. Sodium, the potassium, the chloride. So, some of the things that can be in there are CATMUDPILES and we're just going to go over how a patient who could she come to me with an anion gap metabolic acidosis and have some neuro-ophthalmic complaint. So, we're going to start with carbon monoxide here. Carbon monoxide is a poison, as you know, most commonly it occurs when patients are using space heaters in their home and they're not properly ventilating people also try to kill themselves by locking themselves in the garage and letting the exhaust fumes overtake them. So, this presents to me as anoxic encephalopathy and cortical vision loss. Aminoglycosides can cause neurotoxicity, ototoxicity, vestibular toxicity. And so, this person with aminoglycoside toxicity comes to me with a disruption of the vestibular ocular reflex so they have dizziness and imbalance, oscillopsia from nystagmus because they can't suppress the vestibular ocular system to match the movement of your head. Toluene is from sniffing paint. So those are like homeless kids who are huffing. They take a paper bag and they huff the paint. Glue sniffing this also comes to me with demyelination in the cortex and can come to me as a cortically blind kid. Methanol that comes to me as a bilateral simultaneous loss of vision acutely usually it's from moonshine so maybe they're consuming somebody's wood alcohol, or they are trying to kill themselves because methanol is in a lot of different home products like windshield washer fluid. So, it presents to us as acute bilateral license loss of vision. We want to dialyze this out and also, we're going to do fomepizole, which is the competitive antagonist the alcohol dehydrogenase. Uremia that causes uremic optic neuropathy. That's one of the causes of patients who have kidney failure. They also need dialysis. And diabetic ketoacidosis. This comes to me as a patient who has an infection. So usually they have the orbital apex syndrome because they have sinus disease that sinus disease is Mucormycosis and a patient who has diabetic ketoacidosis. You have to control the acidosis before you go after the Mucor. Propylene glycol, that really doesn't come to me. INH and ethambutol are in patients who are being treated for tuberculosis and they come with a bilateral slowly progressive central scotoma from a retrobulbar optic neuropathy. So, if we stop the ethambutol but they're still losing their vision, we would be thinking about INH toxicity and we would stop that drug too. Lactate that comes to me from mitochondrial disorders where there's a problem with the mitochondrial production of ATP and the most common things that we see with this are lactic acidosis and stroke-like episodes. So that's MELAS so they have a mitochondrial based encephalopathy with lactic acidosis and stroke-like episodes that can come to me a stroke in the brain or a stroke in the eye. So, they're going to have a lactic acidosis. Ethylene glycol looks similar to methanol. It's usually a toxicity from either an intentional or unintentional exposure to ethylene glycol. This is an antifreeze so people either try and kill themselves, or if it's a kid that's been poisoned, or somebody's trying to poison you. And salicylate doesn't really come to me. This is aspirin. So, if you have a patient who has an awful finding and has an anion gap metabolic acidosis, think about CATMUDPILES. |
| Date |
2019-10 |
| Language |
eng |
| Format |
video/mp4 |
| Type |
Image/MovingImage |
| Collection |
Neuro-Ophthalmology Virtual Education Library: Andrew G. Lee Collection: https://novel.utah.edu/Lee/ |
| Publisher |
North American Neuro-Ophthalmology Society |
| Holding Institution |
Spencer S. Eccles Health Sciences Library, University of Utah |
| Rights Management |
Copyright 2019. For further information regarding the rights to this collection, please visit: https://NOVEL.utah.edu/about/copyright |
| ARK |
ark:/87278/s61p2rmn |
| Setname |
ehsl_novel_lee |
| ID |
1469330 |
| Reference URL |
https://collections.lib.utah.edu/ark:/87278/s61p2rmn |
