Cestodes : Taenia saginata and taenia solium

This presentation includes a brief note on Taenia saginata and Taenia solium mainly focusing on the morphology, life cycle of organism, pathogenesis, clinical features and treatment. A note on prophylaxis is also provided.This presentation mainly focuses for teaching purposes for undergraduate medical students.

1. Cestodes : Taenia Dr Krishnendu L Department of Microbiology GMC Jalgaon

2. Objectives 1 2 3 4 5 Introduction Morphology & life cycle Pathogenesis & clinical features Lab diagnosis Treatment 2 Presentation title 20XX

3. Introduction Taenia has been known as an intestinal parasite of man since ancient times. Derived from a Greek word meaning tape or band. T.saginata – beef tapeworm T.solium – pork tapeworm 3

4. Morphology & Life cycle

5. Morphology 5 Presentation title 20XX Adult : adult worm is hermaphrodite, grow up to 5m and resides in small intestine. Scolex or head of worm contains 4 cup-like suckers which help in attachment. Strobila or segments are mature, immature and gravid. Mature segments have male and female sex organs and gravid segment has eggs. Eggs are round, 30-40 µm in diameter , acid fast and double walled, enclosing embryo with 6 hooklets .

6. Life cycle 6 Presentation title 20XX

7. Differences between T.saginata & T.solium Feature T.saginata T.solium Definitive host Humans Humans Intermediate host Cattle Pigs Infective form Cysticercus bovis (larvae) Cysticercus cellulosae Eggs Acid fast Non acid fast Clinical presentation Intestinal taeniasis Intestinal taeniasis & cysticercosis Extra intestinal involvement Not seen Cysticercosis cellulosae 7 Presentation title 20XX

8. Clinical features Intestinal taeniasis : mostly asymptomatic, may give history of vague abdominal discomfort, weight loss, diarrhea and pruritic in anal region. Neuro Cysticercosis : most common and serious form, involving brain parenchyma. Can involve spinal cord, sub arachnoid space , meninges and ventricles. Presents with epilepsy, psychiatric disturbances, hydrocephalus etc. it is the second most common cause of intracranial space occupying lesion after TB in India. Ocular Cysticercosis : cysts are found in vitreous humor, subretinal space, & conjunctiva. Blurred/loss of vision, iritis, uveitis and palpebral conjunctivitis are the features. Subcutaneous Cysticercosis : mostly asymptomatic, may present with palpable nodules. Muscular Cysticercosis : acute myositis, fever and eosinophilia. 8 Presentation title 20XX

9. Lab diagnosis Stool examination : Microscopic examination of feces shows bile stained eggs of taenia in 20-80% of cases. Eggs float in saturated salt solution. Formol-ether sedimentation method of stool concentration. Cellophane swab method (NIH swab) Proglottids can be seen in stool sometimes. Antigen detection by ELISA Serodiagnosis : antibody detection by ELISA and IHA . Molecular diagnosis by PCR targeting mitochondrial DNA. 9 Presentation title 20XX

10. Lab diagnosis Diagnosis of cysticercosis : Biopsy / FNAC of lesion Imaging methods like x-ray, CT scan and MRI Serology : antibody detection by ELISA and western blot Antigen detection by ELISA 10 Presentation title 20XX

11. Treatment Praziquantel – 50mg/kg in 3 divided doses for 20-30 days Albendazole – 400mg twice daily for 30 days 11

12. Prophylaxis Avoid intake of raw/ undercooked beef and pork Maintenance of clean personal habits and general sanitary measures Beef and pork should be subjected for effective inspection . Prevention of fecal contamination of soil , proper disposal of sewage Detection and treatment of persons harboring adult worm

13. Thank you I express my sincere thanks to Dr Kishor V Ingole Professor & head Dept of Microbiology