Echinococcus multilocularis

Life Cycle of Echinococcus multilocularis 1. Adult tapeworm occurs in intestine of foxes. Dogs, cats, and coyotes can also serve as definitive hosts. Adult is small - 1-2 mm long

Echinococcus multilocularis Alveolar hydatid cyst in a mouse - cyst metastasizes from the liver to fill the body cavity

Alveolar Hydatid Cyst

Echinococcus multilocularis Liver Cyst multilocular hydatid External budding Extend processes throughout tissues Cirrhosis of liver Thinner membrane Metastasis Advanced cases

Echinococcus multilocularis Not easily operable timing Chemotherapy Praziquantel can increase growth Mebendazole and albendazole given throughout the life of the patient. retards growth Not easily treatable

Echinococcus multilocularis Fox tapeworm Europe, Asia, Americas, New Zealand

Echinococcus multilocularis This species has recently been reported in the upper Midwest (North and South Dakota, Minnesota, Iowa, Nebraska, southern Wisconsin, and Indiana). Recently identified in Illinois, Ohio and Missouri.  

Epidemiology Increasing in Europe Up to 1980’s only in France, Switzerland, Germany, and Austria Spreading throughout Europe.

Epidemiology Increase in fox infection Increase in human infection Still rare Switzerland and Germany Antirabies vaccines Increased fox abundance Movement of foxes Encroachment on urban areas Contact with domestic dogs

Hymenolepis

Hymenolepis Hymenolepis diminuta Hymenolepis nana Rare in humans 90 cm Model tapeworm Hymenolepis nana “Dwarf tapeworm” 40 mm long Common in humans 97.3% children in Moscow 1% children in SE US Cysticercoid

Hymenolepis nana D A 1 B 2 3 4 C

Pathogenesis and Treatment Similar to Adult species of Taenia Praziquantel http://www.npr.org/sections/goatsandsoda/2015/11/04/454066109/a-man-in-colombia-got-cancer-and-it-came-from-a-tapeworm?sc=17&f

Dipylidium caninum

Dipylidium caninum Most common tapeworm of dogs Cats, humans 2 sets of reproductive organs

Gravid proglottids shed Dog eats flea Infective stage?

Diagnostics

Pathogenesis and Treatment Similar to Adult species of Taenia Praziquantel

Test II Toxoplasma, Trematodes and Cestodes