Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 35-18: Noninvasive Cestode Infections + Key Features Download Section PDF Listen +++ +++ Essentials of Diagnosis ++ Light infection generally asymptomatic Abdominal discomfort, anorexia, diarrhea seen in heavy infection, which is common, especially in children +++ General Considerations ++ Six tapeworms infect humans frequently The small tapeworms are Hymenolepis nana (dwarf tapeworm, 25–40 mm; can reach 5 cm) Hymenolepis diminuta (rodent tapeworm, 20–60 cm) Dipylidium caninum (dog tapeworm, 10–70 cm) The large tapeworms are Taenia saginata (beef tapeworm, up to 25 m) Taenia solium (pork tapeworm, 7 m) Diphyllobothrium latum (fish tapeworm, 10 m) H nana is the only tapeworm that can be transmitted between humans Infection follows ingestion of food contaminated with human feces Eggs hatch in the intestines, where oncospheres Penetrate the mucosa Encyst as cysticercoid larvae Then rupture after about 4 days to release adult worms Autoinfection can lead to amplification of infection Infection with H nana, the related rodent tapeworm H diminuta, or the dog tapeworm D caninum can also follow accidental ingestion of infected insects +++ Demographics ++ Infections are common in warm areas, especially with poor hygiene and institutionalized populations + Clinical Findings Download Section PDF Listen +++ +++ Symptoms and Signs ++ Light infections are generally asymptomatic Heavy infections may cause Diarrhea Abdominal discomfort Anorexia +++ Differential Diagnosis ++ Chronic fatigue syndrome Chronic hepatitis Irritable bowel syndrome Amebiasis Ascariasis Enterobiasis (pinworm, mostly children) Hookworm disease Strongyloidiasis Celiac disease or tropical sprue Pernicious anemia (D latum) + Diagnosis Download Section PDF Listen +++ +++ Laboratory Tests ++ Diagnosis is usually made based on the identification of characteristic eggs or proglottids in stool Egg release may be irregular, so examination of multiple specimens or concentration techniques may be needed + Treatment Download Section PDF Listen +++ +++ Medications ++ Praziquantel Treatment of choice Dosage is 25 mg/kg orally Not effective against maturing cysts For heavy infections, repeat treatment after 1 week and screen after therapy to document cure Side effects include headache, malaise, dizziness, abdominal pain, nausea Niclosamide Alternative therapy For adults, 2 g chewed is effective Continue therapy daily for 1 week Side effects include nausea, malaise, abdominal pain + Outcome Download Section PDF Listen +++ +++ When to Refer ++ For persistent or progressive infection despite treatment + Reference Download Section PDF Listen +++ + +Craig P et al. Intestinal cestodes. Curr Opin Infect Dis. 2007 Oct;20(5):524–32. [PubMed: 17762788]