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(skĭs″tō-sō′ mē-ă) [″ + soma, body] A deformed fetus with a fissure in the abdomen. The limbs are rudimentary if present.


(shis″tŏ-sō-mī ă-sĭs, skis″tŏ-sō-mī ă-sĭs) [schistosome + -iasis] Any of several parasitic tropical diseases caused by infestation with flukes of the genus Schistosoma that may colonize the urinary tract, mesenteries, liver, spleen, or biliary tree. SYN: bilharziasis; snail fever.

INCIDENCE: Although schistosomiasis is rare in the U.S., it is endemic in Asia, Africa, South America, and some Caribbean islands. Nearly 240 million people are affected worldwide, 85% of whom live in Africa. Schistosomiasis ranks second after malaria as a socioeconomic and public health problem in tropical and subtropical areas.

CAUSES: Infestation occurs by wading or bathing in water contaminated by cercariae that parasitize freshwater snails or bivalve mollusks.

SYMPTOMS AND SIGNS: Symptoms include abdominal pain, cough, diarrhea, eosinophilia, fatigue, fever, genital sores (which increase vulnerability to HIV infection), and hepatosplenomegaly.

DIAGNOSIS: Diagnosis is made by enzyme-linked immunosorbent assay (ELISA) or by microscopic identification of eggs in stool or the urine.

PREVENTION: The best prevention is elimination of the freshwater snails that are the natural reservoir of the disease, for which acrolein (a contact herbicide for controlling algae and submersed and floating weeds), copper sulfate, and niclosamide (a taeniacide) can be used. Snail populations can also be controlled by introducing or increasing crayfish populations.

TREATMENT: The drug of choice is praziquantel.


(skĭs″tō-sō′mĭ-sī) [″ + ″ + L. cidus, killing] A drug or toxin that kills parasites of the genus Schistosoma.


(skiz″en″sef′ă-lē)[schizo- + encephalo-] The presence of one or more clefts running lengthwise through the cerebral hemispheres. This rare disorder results in developmental delays and seizures in affected children.

schizo-, schiz-

[Gr. schizein, to split]Prefixes meaning division.


(skĭz-ŏg′ō-nē) [″ + gone, seed] Asexual reproduction by fission of a cell. Malarial parasites and species of sporozoa (such as Cryptosporidium) can reproduce using schizogony. They can also reproduce sexually.


(skĭz′oyd) [″ + eidos, form, shape] 1. Severely introverted; socially isolated; lacking close personal relationships or the ability to form them. 2. Resembling schizophrenia.


(skĭz′ŏnt) [″ + ontos, being] 1. A stage appearing in the life cycle of a sporozoan protozoon resulting from multiple division or schizogony. 2. A stage in the asexual phase of the life cycle of Plasmodium organisms found in red blood cells. By schizogony, each gives rise to 12 to 24 ...

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