A Man’s Seizures Turned Out to Be Caused by Dead Tapeworms in His Brain

A Man’s Seizures Turned Out to Be Caused by Dead Tapeworms in His Brain
A close-up look at the scolex, or head, of a fully mature pork tapeworm. Interestingly enough, cysticercosis is what happens when the tapeworms don't get the chance to become adults. (Image: Roberto J. Galindo/Wikimedia Commons)

Coming down with seizures would be a scary experience no matter what, but for one unfortunate man, that experience was compounded by the discovery that dead tapeworm cysts lodged in his brain for decades were the root cause. Thankfully, his seizures were treated successfully, and the man seems to have made a recovery in the years since.

Doctors in Massachusetts described the patient’s case in a paper out last week in the New England Journal of Medicine. According to the report, which included his wife’s testimony, the 38-year-old man had fallen out of his bed at 4 a.m. He then began shaking and speaking gibberish. When police and emergency medical services arrived, he was “combative and disoriented” and initially refused to go to the hospital in an ambulance. On his way to the emergency room, he experienced a two-minute-long seizure and was given a sedative commonly used for seizures.

The man had no history of underlying health problems, and, according to his family, he had been completely fine the day before. Once doctors were able to run CT and MRI scans of his brain, though, the likely culprit of his illness was found: calcified and long-since-dead larval tapeworm cysts. Doctors then concluded that he had a relatively rare form of infestation from the pork tapeworm (Taenia solium), known as neurocysticercosis.

A pork tapeworm infestation can broadly manifest in two ways. If we ingest tapeworms found in pork or other undercooked meat that have matured a bit into cysts, these cysts will migrate to our intestines and bloom into full-blown adult tapeworms — uncomfortably long, weight-loss-inducing parasites. These worms will produce eggs that get pooped out and potentially find their way back to other animals like pigs, so that the cycle can start all over again.

But if another human or even the same infected human then ingests these eggs, the new generation of worms reaches a dead end and can only mature into their cyst form of life. Unfortunately, the nightmare doesn’t end there, because these cysts can still wreck havoc wherever they end up. When they get stuck in the brain, they can cause pressure and trigger inflammation that leads to all sorts of neurological symptoms, including seizures and even death. But it can take years or decades following infestation for symptoms to show up, often only after the worm cysts die (adult tapeworms can live up to 30 years in a host; cysts have a shorter lifespan of around five years). Sometimes, the cysts and the trouble they cause can be confused for a brain tumour.

Locally acquired tapeworm infestations are rare in the U.S. but remain very common in developing countries. And the doctors’ best guess is that their patient first played host to these worms at least 20 years ago in his native home of Guatemala, before he migrated to the U.S.

Following treatment with anti-seizure medication and steroids, the man’s condition (including the swelling around the lesions in his brain) improved enough that he was discharged from the hospital by day five. Though the cysts can sometimes be removed surgically or treated with antiparasitics if they’re still alive, that’s often not possible or needed, and patients who have had seizures will instead be given long-term medication to manage or prevent them in the future, as was the case here. Luckily, follow-up visits three years later have found that the man hasn’t had any episodes of seizure since and that he remains in good health.

While neurocysticercosis is relatively rare here, it’s one of the leading causes of seizures that show up in adulthood worldwide. Even in the U.S., about 1,000 people are hospitalized as a result every year. Cysticercosis in general is considered a neglected tropical disease, and according to the Centres for Disease Control and Prevention, there is currently “little being done to monitor, prevent, or identify and treat neurocysticercosis.”