Parasitic tapeworm infections affect tens of millions of people worldwide, particularly in areas within Asia, Africa and Latin America employing substandard methods of sanitation and hygiene. All tapeworms spend part of their life cycle living in the feces of humans or other animals, and are thus only transmissible between hosts via some form of fecal-oral contact. Tapeworms cause a variety of diseases in humans, and treatment accordingly varies depending on the type of infection.
Treatment of Cysticercosis
Ingestion of food or water contaminated with human feces containing tapeworm eggs causes an illness called cysticercosis, wherein tapeworm embryos hatch from their eggs in the small intestine, burrow through the intestinal wall into the bloodstream, and disseminate to form larva-containing cysts (i.e., cysticerci) throughout the body, most often in the brain, striated muscle and liver. Symptoms are then caused by the body's immune reaction to the developing cysticerci wherever they are located. The manifestations of disease particular to a given case will dictate the necessary treatment and will vary depending on the site and severity of the infection.
Cysticerci located in the liver or in muscle do not typically warrant treatment, as they are most often asymptomatic. When symptoms do occur, they consist mainly of pain localized to the site of infection, which tends to respond to over-the-counter painkillers. Especially painful or unsightly subcutaneous lesions can be removed surgically.
Treatment of Neurocysticercosis
Neurocysticercosis, or larval tapeworm infection of the brain, is potentially fatal and predisposes the sufferer to seizures, confusion, nausea / vomiting and headache. Treatment therefore focuses on seizure control and prophylaxis with standard anti-epileptic medication such as phenytoin or carbamazepine. Simultaneously, corticosteroids are administered to attenuate the body's immune response, while antiparasitic therapy, consisting of either albendazole or praziquantel, is used to kill the cysticerci directly. Depending on the location of cysticerci within the brain, neurosurgery may also be necessary.
Treatment of Taeniasis
Consumption of undercooked pork, beef or fish harboring cysticerci results in taeniasis, or parasitic infection by an adult tapeworm: the tapeworm larvae within the cysticerci exit and attach to the lining of the intestinal wall, from which they feed, grow to adulthood and reproduce, reaching a length inside the GI tract of up to 25 meters (75 feet). Treatment of taeniasis is straightforward, and consists essentially of killing the tapeworm with one to two doses of praziquantel. This eradicates all tapeworm infections with greater than 95 percent efficacy.
In rare cases, multiple tapeworms living in a single GI tract can get tangled up with one another, forming a mass large enough to cause an intestinal obstruction. This is a life-threatening emergency and requires immediate surgical intervention to remove the obstruction.
References
- Flisser, A, Viniegra, AE, Aguilar-Vega, L, et al. Portrait of human tapeworms. J Parasitol 2004; 90:914.
- Garcia, HH, Evans, CA, Nash, TE, et al. Current consensus guidelines for treatment of neurocysticercosis. Clin Microbiol Rev 2002; 15:747.
- 24. Drugs for Parasitic Infections. Medical Lett Drugs Ther; August 2004.
