Neurocysticercosis is a specific form of the infectious parasitic disease

cysticercosis Cysticercosis is a tissue infection caused by the cysticercus, young form of the Taenia solium, pork tapeworm. People may have few or no symptoms for years. In some cases, particularly in Asia, solid lumps of between one and two centimetres may ...

that is caused by the infection with ''

Taenia solium ''Taenia solium'', the pork tapeworm, belongs to the cyclophyllid cestode family Taeniidae. It is found throughout the world and is most common in countries where pork is eaten. It is a tapeworm that uses humans as its definitive host and pigs ...

'', a

tapeworm Eucestoda, commonly referred to as tapeworms, is the larger of the two subclasses of flatworms in the class Cestoda (the other subclass is Cestodaria). Larvae have six posterior hooks on the scolex (head), in contrast to the ten-hooked Cestodar ...

found in pigs. Neurocysticercosis occurs when

cyst A cyst is a closed sac, having a distinct envelope and cell division, division compared with the nearby Biological tissue, tissue. Hence, it is a cluster of Cell (biology), cells that have grouped together to form a sac (like the manner in which ...

s formed by the infection take hold within the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...

, causing neurologic syndromes such as

epileptic seizures An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with los ...

. It is a common cause of seizures worldwide. It has been called a "hidden epidemic" and "arguably the most common parasitic disease of the human nervous system". Common symptoms of neurocysticercosis include seizures, headaches, blindness, meningitis and dementia.

Signs and symptoms

Pathophysiology

Neurocysticercosis most commonly involves the

cerebral cortex The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consisting of ...

followed by the

cerebellum The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebel ...

. The

pituitary gland In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland, about the size of a chickpea and weighing, on average, in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The ...

is very rarely involved in neurocysticercosis. The cysts may rarely coalesce and form a tree-like pattern which is known as racemose neurocysticercosis, which when involving the pituitary gland may result in multiple pituitary hormone deficiency.

Diagnosis

Neurocysticerosis is diagnosed by computed tomography (CT) scan. Diagnosis may be confirmed by detection of antibodies against cysticerci in CSF or serum through

ELISA The enzyme-linked immunosorbent assay (ELISA) (, ) is a commonly used analytical biochemistry assay, first described by Eva Engvall and Peter Perlmann in 1971. The assay uses a solid-phase type of enzyme immunoassay (EIA) to detect the presence ...

or immunoblotting techniques.

Treatment

Treatment of neurocysticercosis includes epileptic therapy and a long-course medication of

praziquantel Praziquantel (PZQ), sold under the brandname Biltricide among others, is a medication used to treat a number of types of helminthiasis, parasitic worm infections in mammals, birds, amphibians, reptiles, and fish. In humans specifically, it is us ...

(PZQ) and/or

albendazole Albendazole (also known as albendazolum) is a broad-spectrum anthelmintic and antiprotozoal agent of the benzimidazole type. It is used for the treatment of a variety of intestinal parasite infections, including ascariasis, pinworm infection, h ...

. Steroid therapy may be necessary to minimize the inflammatory reaction to dying cysticerci. Surgical removal of brain cysts may be necessary, e.g. in cases of large parenchymal cysts, intraventricular cysts or

hydrocephalus Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased intracranial pressure, pressure inside the skull. Older people may have headaches, double vision, poor ...

. Albendazole has been shown to reduce seizure recurrence in those with a single non-viable intraparenchymal cyst. For seizures further

randomized controlled trial A randomized controlled trial (or randomized control trial; RCT) is a form of scientific experiment used to control factors not under direct experimental control. Examples of RCTs are clinical trials that compare the effects of drugs, surgical te ...

s are needed to evaluate the efficacy of

antiepileptic drugs Anticonvulsants (also known as antiepileptic drugs or recently as antiseizure drugs) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of b ...

(AED) for seizure prevention in patients with symptoms other than seizures and the duration of AED treatment in these cases.

Epidemiology

The epidemiology of ''Taenia solium'' cysticercosis is associated with poor sanitation and is highly prevalent in Sub-Saharan Africa, Latin America and Asia. Cysticercosis in the United States, which commonly presents in the form of neurocysticercosis, has been classified as a "

neglected tropical disease Neglected tropical diseases (NTDs) are a diverse group of tropical disease, tropical infections that are common in low-income populations in Developing country, developing regions of Africa, Asia, and the Americas. They are caused by a variety ...

", which commonly affects the poor and homeless, particularly those without access or in the habit of inadequate hand-washing and in the habit of eating with their hands.

References

{{Reflist Brain disorders Helminthiases Parasitic diseases associated with beef and pork consumption