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160 SEcTioN ii Microbiology ` microbiology—Parasitology Microbiology ` microbiology—Parasitology

Cestodes (tapeworms)
orgaNism Disease traNsmissioN treatmeNt
Taenia solium A Intestinal tapeworm Ingestion of larvae encysted in Praziquantel
undercooked pork
Cysticercosis, Ingestion of eggs in food Praziquantel; albendazole for
neurocysticercosis (cystic contaminated with human neurocysticercosis
CNS lesions, seizures) B feces
Diphyllobothrium Vitamin B 12 deficiency Ingestion of larvae in raw Praziquantel
latum (tapeworm competes for B 12 freshwater fish
in intestine) Ž megaloblastic
anemia
Echinococcus Hydatid cysts D (“eggshell Ingestion of eggs in food Albendazole
granulosus C calcification”) in liver E ; cyst contaminated with dog feces
rupture can cause anaphylaxis Sheep are an intermediate host

A B C D E
Liver

St

Trematodes (flukes)
orgaNism Disease traNsmissioN treatmeNt
Schistosoma Liver and spleen enlargement Snails are intermediate host; Praziquantel
A (S mansoni, egg with cercariae penetrate skin of
lateral spine A ), fibrosis, humans in contact with
inflammation, portal contaminated fresh water (eg,
hypertension swimming or bathing)
Chronic infection with
B S haematobium (egg with
terminal spine B ) can lead
to squamous cell carcinoma
of the bladder (painless
hematuria) and pulmonary
hypertension
Clonorchis sinensis Biliary tract inflammation Undercooked fish Praziquantel
Ž pigmented gallstones
Associated with
cholangiocarcinoma

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