報告人：張聰舜 報告日期： 2006-2-13

1. 報告人：張聰舜 報告日期：2006-2-13

2. A male immigrant from Mexico was seen in the dermatology clinic at a California hospital for examination of a large, painless, cutaneous ulcer on his ear. There was evidence of cartilage destruction in the area. A biopsy specimen was taken from the skin lesion and was sent to the laboratory for examination. A section stained with hematoxylin and eosin showed small, oval, nonflagellated protozoan amastigotes. A diagnosis of a blood-borne parasitic infection was made, based on the morphological appearance of the Giemsa-stained smear.

3. Leishmania mexicana complex

4. Classification • 原生動物界（Protista）－原生動物亞界（Protozoa）－變形鞭毛蟲門（Sarcomastigophora）－鞭毛蟲亞門（Mastigophra）－動鞭毛蟲綱（Zoomastigophorea）－動質蟲目（Kinetoplastida） • 利什曼原蟲（Leishmania） • 錐蟲（Trypanosoma）

5. Classification • L. donovani • L. donovani donovani、L. donovani chagas、L. donovani infantum • L. tropica • L. tropica aethiopica、 L. tropica major、 L. tropica minor、 L. tropica tropica • L. maxicana • L. maxicana amazonensis、 L. maxicana mexicana、 L. maxicana pifanoi • L. viannia（L. braziliensis） • L. viannia braziliensis、L. viannia guyanensis、L. viannia panamensis、L. viannia peruviana

6. Classification

7. Epidemiology • North-Eastern China, India, Middle-East, Southern Europe (Mediterranean bassin), Northern Africa, Central-East Africa and, in foci, Central and South America (especially Brazil and Honduras).

8. Epidemiology • O.W.L. is found especially in Asia (Middle East), Northern Africa and Southern Europe. • N.W.L. has a wide distribution in Central and South America (from Yucatan to Brazil). • The mucocutaneous form is prevalent in South America.

9. Life Cycle • 無鞭毛體 amastigote (Leishman-Donovan body) • found intracellularly in the vertebrate (i.e., human) host • 前鞭毛體 promastigote (leptomonad) • found in the digestive tract of the invertebrate host

10. Life Cycle

11. Vector • Sandfly（白蛉）：order Diptera（雙翅目）－family Phlebotomidae（白蛉科）or Psychodidae （毛蠓科 ）. It includes the genera as follows： • Phlebotomus genus（白蛉屬） • Lutzomyia genus（沙蠅屬） • Psychodopygus genus

12. Sandfly • small size, long legs, and abundant hair on both wings and body • flying, biting, blood-sucking insect • Most sandflies will bite any warm-blooded animal and one species attacks penguins. • Only female sandflies bite • New world－ Lutzomyia • Old world－ Phlebotomus

13. Animal reservoirs • 人畜共通病（Zoonosis） • 齧齒目動物 ,樹懶 ,有袋動物 ,食肉動物 • 印度的VsceralLeishmaniasis 幾乎侷限於人 • L. major 在亞洲鄉村是野生齧齒;在亞洲都市是犬;在非洲市齧齒

14. Cutaneousleishmaniasis • O.W.L. is found especially in Asia (Middle East), Northern Africa and Southern Europe. • N.W.L. has a wide distribution in Central and South America (from Yucatan to Brazil). • The mucocutaneous form is prevalent in South America.

15. Cutaneousleishmaniasis • incubation period is 2~8 weeks • erythematous papule nodule nodule ulcerates and crusts • typically large but painless unless there is secondary bacterial or fungal infection. • Old World Cutaneous leishmaniasis • Leishmania, subgenus Leishmania, complexes major, tropica, donovani (infantum species), aethiopica (diffuse form). • dry or urban cutaneous leishmaniasis is caused by Leishmania tropica • wet or rural cutaneous leishmaniasis is caused by L. major • Ethiopian cutaneous leishmaniasis is caused by L. aethiopica • New World Cutaneous leishmaniasis • Leishmania, subgenus Leishmania, complex mexicana (mexicana, amazonensis, pifanoi)and subgenus Viannia, complexes brasiliensis and guyanensis • develop and heal similarly to those of the Old World forms but tend to be less nodular and more ulcerative and destructive • some common forms are mucocutaneous leishmaniasis

16. Old World Cutaneous leishmaniasis • dry cutaneous • large urban areas in the Middle East, the Mediterranean region, and the Indian subcontinent • Leishmania tropica • vectors Phlebotomus sergenti and P. papatasi • reservoir may be either human or canine（犬） • A slowly developing single lesion that persists for a year or more • wet cutaneous • rural areas in parts of the Middle East, central Asia, and the Indian subcontinent • Leishmania major • reservoirs are desert rodents such as squirrels（松鼠） and gerbils （沙鼠） • vector Phlebotomus papatasi • Infection is acute, rapidly evolving, and characterized by multiple sores with inflammation, ulceration, and crusting • Ethiopian cutaneous • the highlands of Kenya and Ethiopia • Leishmania aethiopica • hyraxes（蹄兔） • vectors are Phlebotomus pedifer and P. longipes • less inflamed and more chronic • self-limited but may develop into diffuse cutaneous leishmaniasis

17. Old World Cutaneous leishmaniasis

18. New World Cutaneous leishmaniasis • Mucocutaneous • chronic, progressive metastatic spread of the lesions of New World cutaneous leishmaniasis • Leishmania viannia braziliensis • nasal, pharyngeal, and buccal mucosa months to years after the appearance of the initial cutaneous lesion,which has usually healed. • mutilating destruction of the nasal septum, palate, lips, pharynx, and larynx

19. Diffuse cutaneous leishmaniasis • rare chronic form • Leishmania aethiopica in Ethiopia and Kenya • L. pifanoi in Venezuela • L. viannia in South America • L. mexicana complexes in Central America • local and hematogenous spread from a primary lesion to produce generalized nodular lesions resembling those of lepromatous leprosy in the skin and sometimes involving the nasal mucosa and laryngopharynx.

20. Diagnosis • a history of exposure to sandfies • Risk factors for HIV should besolicited, including sexual encounters, intravenousdrug use, and blood transfusions obtained abroad. • symptoms • isolation of the organisms from the lesion aspirate or biopsy, by direct examination or culture • A skin test (delayed hypersensitivity: Montenegro test) and detection of anti-leishmanial antibodies by immuno-fluorescence are indicative of exposure.

21. Diagnosis

22. Diagnosis • Cutaneous scraping • the simplest and most common test • only 70 to 75 percent sensitive • fixed with methanol, stained with Giemsa, and examined under oil immersion. • Amastigotes are seen in monocytes or extracellularly • It is important to see the nucleus and the rod-shaped kinetoplast, a mitochondrial structure containing extranuclear DNA, to diagnose leishmaniasis.

23. Treatment • Sodium stibogluconate is the drug of choice. • Machanism unknown • Side effect（reversible） • Gastrointestinal symptoms • Fever • Headache • Myalgia , arthralgia • Rash • ECG changes, ex. T waves change and QT prolongation

24. Treatment

25. Quiz 1 • Which infection does this patient have? What is the name of the hemoflagellate causing his infection?

26. Quiz 2 • Name the three main species belonging to this complex.

27. Quiz 3 • Which vector is responsible for the transmission of this infection?

28. Quiz 4 • Describe the life cycle of this parasite.

29. Quiz 5 • What are the reservoirs for these parasites? Which populations are at particular risk of infection with these parasites?

30. Quiz 6 • How is the diagnosis of this infection made?

31. Quiz 7 • How is this infection treated?

32. Reference • 醫用寄生蟲學 • http://www.cdfound.to.it/html/atlas.htm#atlas • http://www.biosci.ohio-state.edu/~parasite/home.html • http://en.wikipedia.org/ • http://www.dpd.cdc.gov/dpdx/Default.htm • http://pathmicro.med.sc.edu/book/welcome.htm • Basic and clinincally pharmacology