Diphyllobotrium latum Sparganosis Taenia spp.

Transcription

1 Introduction of Cestodes Diphyllobotrium latum Sparganosis Taenia spp. ( inter) Asst. Prof. Dr. Atiporn Saeung

2 Additional Readings น ม ตร มรกต, เกต ร ตน ส ขว จน, บรรณาธ การ.ปรส ตว ทยาทางการแพทย โปรโตซ วและ หนอนพยาธ.พ มพ คร งท 2. เช ยงใหม : คณะแพทยศาสตร มหาว ทยาล ยเช ยงใหม, น ม ตร มรกต, คม ส คนธสรรพ, บรรณาธ การ. ปรส ตว ทยาทางการแพทย II. หนอนพยาธ. พ มพ คร งท 3. เช ยงใหม : คณะแพทยศาสตร มหาว ทยาล ยเช ยงใหม, Markell EK, Voge M, John DT. Medical parasitology. 8 th ed. Philadelphia: W.B. Saunder; Muller R. Worms and Human Disease. 2 nd ed. Wallingford: CABI; Roberts LS, Janovy J Jr, Nadler S. Gerald D. Schmidt & Larry S. Roberts' Foundations of Parasitology. 9 th ed. New York: McGraw-Hill;

3 Objectives Be able to explain characters of cestodes Be able to explain life cycle, clinical manifestation, diagnosis, prevention and treatment of diphyllobothriasis, sparganosis, taeniasis and cysticercosis

4 General morphology of cestodes Ribbon-like, multisegmented, hermaphrodite Scolex (head): situated on the neck - equipped with adhesive organs (grooves or suckers with/without rostellum)

5 (contained viable embryonated eggs) Neck: germinative portion Strobila: chain of proglottid Immature -> Mature proglottid Mature-> Gravid proglottid -> Eggs

6 No digestive system (food absorbed through tegument) Reproductive system: - not formed in anteroir ploglottid - well-developed in posterior ploglottid Excretory system : - dorsal, ventral, transverse nephridial canals, finally open at posterior end of last ploglottid Nervous system : - R & L longitudinal nerve cords araise from nerve rings (at scolex) and pass posteriorly along the ploglottid

7 Scolex Immature Mature Gravid proglottid

8 Medical important Tapeworm 1. Order Pseudophyllidea - Diphyllobothrium latum - Spirometra spp. 2. Order Cyclophyllidea - Family Taeniidae: Taenia solium, T. saginata, Echinococcus granulosus, E. multicularis - Family Hymenolepiddidae: Hymenolepis nana, H. diminuta - Family Dilepididae: Dipylidium caninum

9 Scolex Pseudophyllidea spoon-like 2 longitudinal grooves bothria Cyclophyllidea round or square sucker w or w/o rostellum (w/o hookltes)

10 Pseudophyllidea Cyclophyllidea Genital pore & uterine pore G U G ventral lateral

11 Pseudophyllidea Cyclophyllidea egg operculum no embryo No operculum embryo (hexacanth onchosphere)

12 Life cycle Adult worms (in small intestine of Definitive host) Ingestion Larval stages (in intermediate hosts) Eggs (in feces) Tapeworms are heteroxenous, except Hymenolepis nana

13 [ DH ] ADULT LC of Pseudophyllidea IF PLEROCERCOID [ 2nd IH ] PROCERCOID EGG [Immature] water CORACIDIUM [ 1st IH ] (ciliated oncosphere)

14 [DH] ADULT EGG mature IF METACESTODES [IH] 4 Types ( ~ spp.) Cysticercus, Cysticercoid, Coenurus, Hydatid Cyst LC of Cyclophyllidea (hexacanth embryo or oncosphere)

15 Larvae of Pseudophyllidea worms Procercoid - long body with hooks at the knob-liked posterior end Plerocercoid - wrinkled, ribbon-liked - pseudosucker likes bothria - unsegmented strobila - no internal organ

16 cysticercus Larvae of Cyclophyllidea worms - fluid filled, oval bladder - transparent, thin-walled - inside : scolex cysticercoid - like cysticercus but no fluid - has a tail - inside : scolex

17 Larvae of Cyclophyllidea worms coenurus - white, semi-transparent bladder - filled with clear, watery fluid - budding of protoscolices from geminative membrane of the cyst

18 Larvae of Cyclophyllidea worms

19 Pseudophyllidea Diphyllobothrium latum Spirometra spp.

20 Diphyllobothrium latum Common name: 10 meters long broad or fish tapeworm The longest human tapeworm Disease: Diphyllobothriasis Habitat: small intestine of man and fish-eating mammals

21 Distribution - Northern hemisphere (Europe, USA, Asia) - Uganda, Chile - High prevalence: Finland, Sweden, Lithuania - In Asia: Japan, Taiwan, Philippines - No report in Thailand - Transmitted by Salmon, burbot, trout, and pike fish

22 Morphology Scolex: - elongated 1x3 mm. (spoon-like) - 2 shallow, longitudinal grooves (bothria)

23 Morphology Proglottids: - width > length - genital pore at center - coiled uterus is rosette in appearance

24 Morphology Egg: - Oval or ellipsoidal - Size: 65 x 45 µm. - yellow-brown color - an operculum (lid) - a small knob

25 Life cycle Complex life cycle DH: Fish-eating mammals (Dogs, cats, bears, etc.) 1 st IH: Copepods 2 nd IH: Small freshwater fish Paratenic host: Large predator fish (pike, perch, trout) Prepatent period ~ 5-6 wks

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27 Procercoid in copepod Plerocercoid in fish

28 Clinical features Asymptomatic, long-lasting infection Abdominal discomfort, diarrhea, vomiting, weight loss and weakness Vitamin B12 deficiency -> pernicious anemia Massive infection -> intestinal obstruction

29 Diagnosis, treatment and prevention Eggs or proglottids in stool Praziquantel, niclosamide Cooked fish Freeze C, 1-2 days

30 Spirometra spp. Plerocercoid of Spirometra spp., so called sparganum Sparganosis: larval tapeworm infection of man DH : dogs and cats (adults) 1 st IH : copepods (procercoid) 2 nd IH : frogs, snakes (plerocercoid)

31 Epidemiology Found in most parts of the world Most human cases in China, Korea, Japan, Taiwan and Southeast Asia

32 Morphology Mature ploglottid Egg Similar as D. latum exception: coiled uterus (spring-like) Similar as D. latum

33 Sparganum (Plerocercoid) wrinkled, ribbon-like, ivory larva with x cm in size pseudosegmented, no internal organ movement: contraction and elongation found in human tissue (AH)

34 DH 2 nd IH AH 1 st IH

35 Plerocercoid in snake

36 Transmission to human 3 major routes: 1. Drinking untreated water (copepods infected with procercoid ) 2. Consuming uncooked meat (snake, frog, etc. infected with plerocercoid 3. poultices as folklore medicine (placing frog/snake flesh on wounds/eyes common in Asian cultures)

37 Sparganosis

38 Clinical manifestations Mostly infect to subcutaneous tissues, visceral organs, eyes, lung, brain (seizures, paresthesia) Asymptomatic in early migratory stage At final site: edematous, painful inflammation around tissue (nodule 1-2 cm. in diameter)

39 Diagnosis CT scan or MRI (to localize the lesions) Surgical removing (definitive diagnosis) Serodiagnosis: ELISA (cerebral sparganosis)

40 Treatment Surgical removal of sparganum larvae Praziquantel mg/kg, over 2 days

41 Sparganosis of the breast Nodular fibrofatty tissue and sparganum

42 Ocular sparganosis sparganum

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44 Common name Taenia solium: Pork tapeworm Taenia saginata: Beef tapeworm

45 Geographical distribution Worldwide distribution T. solium is rare in muslim countries In Thailand, both species exist, but T. saginata prevalence is much higher than that of T. solium

46 Morphology Size: Rostellum: Tape-liked with 7-14 mm x m with /without

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48 Morphology (cont.) Taenia solium Taenia saginata Scolex Rostellum/hooklets No rostellum

49 Morphology (cont.) Taenia solium Taenia saginata mature proglottid - Ovary gravid proglottid * - lateral uterine branches trilobed 7-12 branches bilobed branches *

50 Gravid proglottid Taenia solium Taenia saginata

51 Taenia egg * can not be differrentiated - Spherical shape - Walnut-brown in color - Egg shell: thick and radially striated embryophore - Contains hexacanth oncosphere inside

52 IF DH IH

53 Larval stage = Cysticercus - Thin- walled, transparent - round or oval white bladder - Diameter 5-8 mm. - Liquid inside Cysticercus bovis* Cysticercus cellulosae* => Taenia saginata => Taenia solium

54 Larval Stage = Cysticercus Cysticercus cellulosae Cysticercus bovis in pork in Beef

55 Diseases & Symptoms Taeniasis caused by adult worm - Taeniasis saginata /solium - no specific symptoms (abdominal discomfort, hunger pain, headache, etc.) - heavy infection (bowel obstruction, appendicitis, cholecystitis) Cysticercosis* caused by larva stage (cysticercus) - more severe symptoms - Caused by T. solium

56 Cysticercosis Having cysticerci of T. solium in internal organs (brain, muscle, eyes, etc.) Neurocysticercosis : the most severe form headache epilepsy nausea vomiting

57 Cerebral cysticercosis CROSS SECTION

58 Causes of Cysticercosis 1. Eating of food contaminated with T. solium eggs 2. Autoinfection within patients themselves - Internal autoinfection regurgitation of gravid proglottids of T. solium up to the stomach - External autoinfection fecal-oral infection with T. solium eggs

59 ไข พยาธ

60 Diagnosis for taeniasis Stool examination Egg (species can t be identified) Gravid Segment - uterine branches Scolex - Rostellum, Hooks Mature Segment - Reproductive organs: no. of ovary lobes

61 Diagnosis for cysticercosis Brain imaging (to detect calcified cysticerci) - X-ray - CT - MRI (magnetic resonance imaging) Biopsy Serological diagnosis - confirmation test: electroimmunotransfer blot (EITB)

62 CT scan MRI

63 X-ray

64 Treatment Taeniasis - Praziquantel (T. solium), niclosamide (T. saginata) - Single dose of 5-10 mg/kg Cysticercosis: varies depending on type of disease - Albendazole + steroid - Praziquantel - Surgery for cysticerci

65 Prevention Taeniasis - Consuming cooked meat - freezing meat at -5 C, 5 days Cysticercosis - good hygiene - public health education