to study the general characteristics of medically Objectives: to study the general characteristics of medically important tapeworms including their morphology, life cycle,habitat,nutrition, pathogenesis and laboratory diagnosis. -

They have ribbon- like shape, flattened dorsoventrally & segmented . Cestodes ( tape worms) General characters They have ribbon- like shape, flattened dorsoventrally & segmented . All tapeworms have indirect life cycle except Hymenolepis nana. Adult tapeworm inhabits the small intestine of vertebrates. While the larvae inhabit the tissues of vertebrates & invertebrates. All tapeworms are hermaphrodites, They have no gut or digestive tract,absorption of nutrient materials takes place through tegument (body wall). . Adult tapeworms produce minimal intestinal irritation and few systemic effects(mechanical and chemical effects).

Morphology of adult tapeworms ; Adult tapeworm divided in to ; -Scolex or head provided with attachment organs . -Neck or region of growth . -Strobila or chain of segments or proglottids ; 1-Immature proglottids . 2-Mature proglottids. 3-Gravid proglottids.

Types of cestodes larvae; A - Bladder larvae : 1-Cysticercus : e.g. T. solium, T. saginata. 2-Cysticercoid: e.g. Hymenolepis spp. 3-Hydatid cyst : e.g. Echinococcus spp. 4-Coenurus: e.g. Taenia multiceps. B – Solid larvae: 1-Procercoid: e.g. D. latum. 2-Plercercoid (sparganum): e.g. D. latum.

Taenia saginata(beef tape worm) -Disease ; Taeniasis Beef tapeworm infection -Habitat ;Upper part of small intestine – Proglottides;1000-2000 Length;4-10 m Morphology; -Morphology 1-Scolex (unarmed) 2-Neck

3- Strobila; -Immature Mature Gravid Gravid segment ;15 – 30 lateral uterine branches

Bladder larvae : Cysticercus bovis : a true bladder worm, It is oval in shape, has fluid- filled membranous bladder with invaginated unarmed scolex.

Egg of Taenia spp.(S. S. C. C.) size;36 micron, shape; globular or spherical, color; yellowish brown contents; Taenia spp. eggs contain an embryo that is called an oncosphere or hexacanth embryo ,surrounded by thick, radially striated embryophore. The egg surrounded by delicate egg shell.

- Pathogenesis, pathology & symptomatology -Intestinal disturbance -Acute intestinal obstruction -Appendicitis -Hunger pain -Systemic intoxication -Mental worried and embarrassment

Diagnosis 1-General stool examination ( egg and gravid segment ) 2-Perianal swab (Scotch tape slide technique) 3-Examination of scolex (after medication) Treatment Niclosamide, praziquantel and mebendazole.

Taenia solium ( pork tapeworm )

Disease: Taeniasis or pork tape worm infection. Habitat: upper part of Taenia solium (pork tape worm) Disease: Taeniasis or pork tape worm infection. Habitat: upper part of Small intestine of man. Adult: Length: 2-8 m Scolex: armed scolex Strobila; 800-1000

7 – 13 lateral branches

Larva: Cysticercus cellulosae Membranous bladder with Invaginated armed scolex

Cysticercosis : human tissue infection with cysticercus cellulosae Hetero – infection. Auto – infection: External auto-infection. Internal auto-infection.

Intestinal obstruction Appendicitis Abdominal pain and discomfort Pathogenesis ,pathology and symptomatology; Adult worm: Intestinal obstruction Appendicitis Abdominal pain and discomfort Peritonitis in rare cases .

Larval stage: Severity of cysticercosis depend on : Location, Size, Number of larvae and host immune response •Clinical manifestations depend on size of the larvae and type of tissue invaded,mainly it takes place in subcutaneous tissues, skeletal muscles, brain and eye.

Diagnosis Adult: Egg in stool sample(microscopic exam.) Gravid segment(macroscopic exam.) Scolex Larvae: Histopathological exam. of biopsy materials. Serology Radiology, CT scan & MRI.

Taenia multiceps (gid worm) Adult worm , from 40 – 60 cm in length , the scolex with double circle of hooks, it is found in the small intestine of dogs , wolves and foxes . Larval stage is called Coenurus cerebralis is found in CNS of herbivores mammals ( sheep , goat and cattle) , man infected accidentally. larval stage produce a disease known as cerebral and ocular coenurosis .

Coenurus larva Of T.multiceps