| Affiliation |
(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (NW) Class of 2022, Baylor College of Medicine, Houston, Texas |
| Transcript |
So today we're going to be talking about the neuro-op of neurocysticercosis. So, neurocysticercosis is a big problem worldwide. It's a common cause of new onset seizure in young people from endemic areas. So, for example, here in Houston, Texas, if a patient who is from El Salvador or Mexico presents with a new onset seizure we're going to be thinking about neurocysticercosis in a young patient. And the key in differentiating imaging finding on both CT and MRI, as you can imagine, is a cyst in your neuro and that's going to be a cystic lesion. So, anytime we see a cystic lesion with or without the visible worm inside, and what we're seeing is the scolex, the headpiece of the worm. And in this case, neurocysticercosis, the worm is Taenia. So Taenia solium is the tapeworm. It lives in the pig and because a large proportion of the pigs in certain endemic parts of the world, including Mexico, are infested with this we might get neurocysticercosis from this. The way it presents in neuro-op, as you can imagine, is signs of increased intra-cranial pressure. For example, papilledema or a non-localizing 6th nerve palsy. Or it can cause obstructive hydrocephalus either from the cyst compressing the ventricular outflow or the cyst inside the ventricle. And those findings are the typical signs of hydrocephalus and increased intracranial pressure including the dorsal midbrain syndrome. So, when we're confronted with a patient with neurocysticercosis we're really looking at two things. One is the neuro-op features of increased intra-cranial pressure from the neurocysticercosis lesion and also we want to make sure it's not the ophthalmologic manifestations of neurocysticercosis because if we see the cysts in the eye, as you know, the organism can protect itself and resist immunologic recognition by coating itself with mucous. And so, if it's a cyst in your eye it's still alive and the body won't recognize it as a foreign body and then when we kill it with medications, such as praziquantel or albendazole, that is what leads to the inflammatory response, the massive vitritis, that can be quite devastating to someone if they have a cyst in the eye. So before we start the treatment for neurocysticercosis we want to do a dilated fundus examination and make sure that we don't have the worm in our eye and we have to do the treatments that are going to be necessary for the worm before we start treating the systemic disease, because killing the worm might lead to a massive inflammatory response that can actually make the patient worse. The other thing you need to know about the tapeworm is - and my residents often tell me this - that they're going to Mexico or someplace that is endemic with the pork tapeworm. And they'll say, "Well I don't eat pork" or "I'm Muslim, I don't eat pork", or "I'm a vegetarian, I don't eat pork". But that's not actually how you get neurocysticercosis. They way that you get neurocysticercosis, in addition to eating uncooked pork products, is exposure to the cysts. And those are coming out from muscular proglottids that have migrated out of the intestine in the infected individual. And that means it can be on lettuce and fruit and in the water. So, it's from stool that's got the cysts in it and so it doesn't matter if you don't eat pork in these endemic countries. The way you get it is from getting exposure to the stool and if you're exposed to the stool and the cyst is on there then you'll get neurocysticercosis. So, we follow the CBC recommendations for general hygiene, and these include the prophylaxis against the tapeworm which is don't eat anything unless you washed it yourself, peeled it yourself. Don't eat anything uncooked- so salads and things like that. That's how you get exposed to this organism. And I recommend drinking bottled water, including brushing your teeth with the bottled water. So, bottled water that you opened yourself, wash things or cook things- I recommend that you eat only cooked food. And that way you can avoid getting accidently exposed to neurocysticercosis and the neuro-op manifestations of the organism. |
