Answer: Neurocysticercosis is a potentially fatal parasitic infection that affects the brain.
CT scan showing cysts
The pork tapeworm Taenia solium is a parasite that can live in the human body. When the infection spreads to the central nervous system, it is called neurocysticercosis. The infection begins when a person ingests the tapeworm eggs, which are often found in contaminated food and water. Once inside the body, the tapeworm undergoes their life cycle. The eggs hatch into larvae which can migrate into the brain. The larvae form cysts, which leads to many different symptoms.
Symptoms of neurocysticercosis
The most common immediate symptom are headaches. These may be accompanied by nausea and vomiting. All of these likely occur because of the widespread inflammation of the nervous system, particularly to the meninges, which are the layers of membrane that surround the brain and spinal cord. Inflammation leads to compression of the brain tissue.
New onset of adult seizures without a diagnosis of epilepsy is another symptom. These seizures can be minor, such as an absence seizure, which appears as if a person is suddenly staring and unresponsive. However, in severe cases, neurocysticercosis can cause grand mal seizures, which cause muscle convulsions and loss of balance. Many different types of seizures can happen in neurocysticercosis.
Cognitive impairment may also result from infection. This may include a difficulty with memory and attention. These symptoms make it difficult for the patient to perform their daily activities.
Other symptoms include difficulty with coordination, balance, and vision.
Symptoms can range in severity. If gone untreated, they may last for months and years. The most severe cases of neurocysticercosis result in permanent brain damage or death.
Diagnosing and treating neurocysticercosis
Diagnosing neurocysticercosis can be difficult, since the reported symptoms are often common across many other more common conditions, such as meningitis. Some people also have no symptoms.
Neurocysticercosis may be detected with structural imaging of the brain, such as a CT scan or MRI scan. Both of these are capable of detecting the cysts in the brain tissue.
A serological test can also be done by taking a sample of blood. A person with a tapeworm infection will start producing antibodies against the parasite, and the presence of these antibodies in the blood suggest an underlying infection.
The treatment for the infection is to remove the parasite from the body. A class of drugs called “antihelminthics” are often used for this purpose. Albendazole is one example of an antihelminthic that may be diagnosed for treatment of the tapeworm larvae.
These are often prescribed alongside corticosteroids to help reduce the inflammation.
Epidemiology and causes of neurocysticercosis
Neurocysticercosis is rare in the United States, but it is a public health problem in many developing countries around Latin America, Africa, and Asia.
Prevention measures against neurocysticercosis are aimed at decreasing exposure to the tapeworm and minimizing transmission in the first place. Generally, this includes fully cooking pork products, thoroughly washing vegetables, and good hygiene practices such as handwashing.