1. Mark K. Huntington, MD PhD FAAFP Sioux Falls Family Medicine Residency and University of South Dakota Tissue-Dwelling Parasites

2. NOTICE: ► As presented at AAFP-CIHI 2009, this lecture was amply illustrated with many images – some of whose position in the public domain is not clear. To comply with potential copyright issues, all images have been removed from this online version. Sorry (you should have been here!). ► MKH - 12 Sept 2009

3. A Two-Part Series ► Lumen-dwelling parasites ► Tissue-dwelling parasites

4. Tissue-dwelling Parasites ► Located in tissues rather than the lumen of hollow organs ► Include nematodes, cestodes, trematodes, flagellates, apicomplexa, and amoebae ► Order of lecture will follow affected tissue (mostly)

5. Challenges to Interventions ► Penetration of drug ► Toxicity of drug ► Resistance of parasite ► Elimination of parasite ► Infection vs. disease ► Immunization challenges

6. Central Nervous System ► Naegleria et al ► African trypanosomiasis ► Toxoplasmosis ► Cysticercosis ► Hydatid disease

7. Naegleria

9. African trypanosomiasis

10. Winterbottom’s sign

11. Key points ► Vector-borne (Tse tse fly) ► Associated eponym: Winterbottom’s sign ► Diffuse CNS findings

12. Toxoplasmosis

13. What’s wrong with this picture?!

14. Key points ► Common, generally asymptomatic ► Prenatal: part of TORCH syndrome ► Immunocompromise: HIV, etc.

15. Cysticercosis

16. Tapeworm lifecycle ►T►T►T►Two hosts, two stages

17. Key points ► Most cysticera are asymtomatic ► Neurocysticercosis is a leading cause of seizure disorder in endemic regions ► Prevention: hygiene and sanitation

18. Hydatid disease

19. Key points ► Most hydatid cysts are symtomatic ► Highly allergenic ► Prevention: hygiene and sanitation

20. Eye parasites ► Toxoplasmosis ► Occular cysticercosis ► Acanthamoeba ► Onchocerciasis ► Loiasis ► Occular larval migrans

21. Toxoplasmosis

22. Cysticercosis

23. Acanthamoebae

24. Acanthamoebiasis

25. Emerg Inf Dis 2009;15:1236-42

26. Key points ► Normally, a free-living amoeba ► (may contain Legionella) ► Strongly associated with contact lenses

27. Onchocerciasis

28. Key points ► Vector-borne (black fly) ► Pathology due to inflammation ► Treatment is a success story… so far!

29. Loa loa

30. Key points ► Vector-borne (deer fly) ► Microfilaria circulate during the day ► Associated eponym: Calabar swelling

31. Integumentary parasites ► Onchocerciasis ► Leishmaniasis ► Dracontiasis ► Cutaneous larval migrans ► Myiasis ► Misc. arthropods

32. Onchodermatitis

33. Key points ► Inflammation due to dead microfilariae ► Associated eponym: Mazzotti reaction ► (cf. earlier Onchocerca slide)

34. Leishmaniasis

35. “Dry” lesion

36. “Wet” lesion

37. “Espundia”

38. Lymphatic spread

39. Disseminated cutaneous

40. Post-kala azar dermatitis

41. Kala azar

42. Key points ► Vector-borne (sand fly) ► There are cutaneous, mucocutaneous, and visceral forms ► Treatments are fairly toxic

43. Dracontiasis

44. Key points ► a/k/a Guinea worm ► Treatment: physical > pharmacologic ► Control: clean water supply

45. Larval migrans

46. Key points ► Toxocara canis and Toxocara cati ► Fecal-oral route; lost in migration ► Cutaneous and visceral forms ► Related to our pet addiction in U.S.

47. Myiasis

48. Misc. arthropods ► Flies ► Mosquitoes ► Fleas ► Lice ► Mites ► Ticks

49. Flies and mosquitoes ► Feed on you  Fly larvae ► myiasis (just disgust, er, discussed)  Adults ► Anticoagulants (allergens)  Dermatitis  Research interests ► Some come by day, some by night  Significance as vectors

50. ► Fleas live off, but leap on to feed. ► Lice live on, but may rub off ► Cause pruritic dermatitis ► More than a nuisance…  Bubonic plague  Typhus  Etc. Fleas and Lice

51. Mites and ticks ► Demodex ► Sarcoptes ► Ixodes  Vector for Lyme  also Babesia ► Dermacentor  Vector for RMSF

52. Musculoskeletal parasites ► Cysticercosis ► Hydatid disease ► Trichinosis ► Chagas disease

53. Trichinosis

54. Key points ► From eating pink pork ► Parasite lives in “nurse cell” ► A public health success story

55. Chagas’ Disease

56. Romaño’s sign

57. Infection Chronic CardiomyopathyMegasyndromes Latent (years) Acute Fever, Malaise AsymptomaticLymphatic activity Parasitemia Cardiac malfunction 2-3 weeks

58. Key points ► Vector-borne (reduviid bug) ► Pathology is immune-mediated ► Leading cause of heart failure in endemic regions ► Associated eponym: Romaño’s sign

59. Circulatory system parasites ► Malaria (separate lecture) ► Babesiosis ► Trypanosomiasis  African (already covered)  American (already covered) ► Filariae  Loiasis (already covered)  Lymphatic filariasis

60. Babesiosis ► Of minor medical importance ► Vector: Ixodes tick (like Lyme disease)  Often co-existent with other tick-borne infections ► Intra-erythrocytic (like malaria)

61. Lymphatic filariasis

62. Key points ► Vector-borne (mosquitoes) ► Microfilaria circulate at night ► Physiological, not anatomic, means of pathogenesis ► Wolbachia symbiotic bacteria…

63. Remember Onchcerca?

64. Maybe all filariae are lymphatic…

65. Digestive tissues (extralumenal) ► Hepatobiliary  Amoebae  Geohelminths  Flukes (covered in lumen parasites) ► Mesentery  Schistosomiasis

66. Schistosomiasis

67. Other manifestations of schistosomiasis: ► Hematuria ► Colon polyps ► Swimmer’s itch

68. That’s the tissue parasites…

69. So… how do you treat them?

70. Simplistic antiparasitic primer ► Leishmaniasis  antimonials, amphotericin ► Amoebiasis  Flagyl, amphotericin ► Trypanosomiasis  African - Suramin - Pentamadine - Melarsoprol - Eflornithine  American - Nifurtimox - Benznidazole ► Toxoplasmosis  Pyrimethamine ► Filariae  DEC, ivermectin ► Platyhelminths  Praziquantel ► Dracunculis ► Larval migrans  Albendazole ► Trichinella  Mebendazole

71. Simplistic antiparasitic primer ► Leishmaniasis  antimonials, amphotericin ► Amoebiasis  Flagyl, amphotericin ► Trypanosomiasis  African - Suramin - Pentamadine - Melarsoprol - Eflornithine  American - Nifurtimox - Benznidazole ► Toxoplasmosis  Pyrimethamine ► Filariae  DEC, ivermectin ► Platyhelminths  Praziquantel ► Dracunculis ► Larval migrans  Albendazole ► Trichinella  Mebendazole

72. Bibliography The images used in this lecture may be found in the following sources: The images used in this lecture may be found in the following sources: ► Blaum & Omura’s Images in Clinical Medicine, NEJM 338:1733 ► Gardiner, Fayer, & Dubey, An Atlas of Protozoan Parasites in Animal Tissues ► Google internet search ► Gutierrez’s Diagnostic Pathology of Parasitic Infections ► Halstead & Warren’s Diseases of Travelers and Immigrants ► Hunter’s Tropical Medicine and Emerging Infectious Diseases ► Katz, Despommier & Gwadz’s Parasitic Diseases ► Markell & Voge’s Medical Parasitology ► Peters & Gilles’s A Color Atlas of Tropical Medicine and Parasitology ► Reeder & Palmer’s The Imaging of Tropical Diseases ► J.F. Williams personal collection (And actually, a few of the pictures were mine, too.)