Cysticercosis

An infection caused by the pork tapeworm, Taenia solium. Infection occurs when the tapeworm larvae enter the body and form cysticerci (SIS-tuh-sir-KEY) (cysts). When cysticerci are found in the brain, the condition is called neurocysticercosis (NEW-row SIS-tuh-sir-KO-sis). The tapeworm that causes cysticercosis is found worldwide. Infection is found most often in rural, developing countries with poor hygiene where pigs are allowed to roam freely and eat human feces. This allows the tapeworm infection to be completed and the cycle to continue. Infection can occur, though rarely, if you have never traveled outside of the United States. Taeniasis and cysticercosis are very rare in Muslim countries where eating pork is forbidden. Cysticercosis is contracted by accidentally swallowing pork tapeworm eggs. Tapeworm eggs are passed in the bowel movement of a person who is infected. These tapeworm eggs are spread through food, water, or surfaces contaminated with feces. This can happen by drinking contaminated water or food, or by putting contaminated fingers to your mouth. A person who has a tapeworm infection can reinfect themselves (autoinfection). Once inside the stomach, the tapeworm egg hatches, penetrates the intestine, travels through the bloodstream and may develop into cysticerci in the muscles, brain, or eyes. The signs and symptoms of the disease depend on the location and number of cysticerci in the body. Cysticerci in the muscles: Cysticerci in the muscles generally do not cause symptoms. However, you may be able to feel lumps under your skin. Cysticerci in the eyes: Although rare, cysticerci may float in the eye and cause blurry or disturbed vision. Infection in the eyes may cause swelling or detachment of the retina. Cysticerci in the brain or spinal cord (neurocysticercosis): Symptoms of neurocysticercosis depend upon where and how many cysticerci (often called lesions) are found in the brain. Seizures, and headaches are the most common symptoms. However, confusion, lack of attention to people and surroundings, difficulty with balance, swelling of the brain (called hydrocephalus) may also occur. Death can occur suddenly with heavy infections. Symptoms can occur months to years after infection, usually when the cysts are in the process of dying. When this happens, the brain can swell. The pressure caused by swelling is what causes most of the symptoms of neurocysticercosis. Most people with cysticerci in muscles won’t have symptoms of infection. Diagnosis can be difficult and may require several testing methods. The health care provider will usually ask about where the patient has traveled and their eating habits. Diagnosis of neurocysticercosis is usually made by MRI or CT brain scans. Blood tests are available to help diagnose an infection, but may not always be accurate. If surgery is necessary, confirmation of the diagnosis can be made by the laboratory.

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1. Disease caused by encystment of cysticercus larvae of some tapeworms ( e.g., Taenia solium or T. saginata) in subcutaneous, muscle, or central nervous system tissues; c. is typically developed in swine and cattle, producing measly pork and beef. In humans, it results from the hatching of the eggs of Taenia solium in the intestines or by accidental ingestion of eggs from human feces; encystment in the brain may cause serious nervous damage, and encystment in the eye (usually the rear chamber) may cause ophthalmic damage. 2. Larval infections in animals with other taeniid tapeworm larvae. SYN: cysticercus disease.

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cys·ti·cer·co·sis -(.)sər-'kō-səs n, pl -co·ses -.sēz infestation with or disease caused by cysticerci

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n.

a disease caused by the presence of tapeworm larvae (see cysticercus) of the species taenia in any of the body tissues. Humans become infected on ingesting tapeworm eggs in contaminated food or drink. The presence of cysticerci in the muscles causes pain and weakness; in the brain the symptoms are more serious, including mental deterioration, paralysis, giddiness, epileptic attacks, and convulsions, which may be fatal. There is no specific treatment for this cosmopolitan disease although surgical removal of cysticerci may be necessary to relieve pressure on the brain.

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cys·ti·cer·co·sis (sis″tĭ-sər-koґsis) 1. human infection with cysticerci (larvae of tapeworms of genus Taenia). Those who ingest the eggs of Taenia solium (the pork tapeworm) in contaminated food or water may become infected with the larval stage called Cysticercus cellulosae, which penetrates the intestinal wall and invades the subcutaneous tissue, brain, eye, muscle, heart, liver, lung, peritoneum, and sometimes other sites. Brain involvement is called neurocysticercosis (q.v.). Those who eat incompletely cooked beef become infected with the adult form of Taenia saginata (the beef tapeworm), which can grow to a length of 3.5 to 8 meters in the intestine. Those who ingest the eggs of T. saginata apparently do not become infected with its larval stage called Cysticercus bovis. 2. infection of livestock with cysticerci; this usually occurs as cysts in striated muscles, causing no adverse symptoms. Depending on the animal, it is known as beef measles, pork measles, or sheep measles.