Classification of the Medical Important Protozoa Flagellates 鞭毛蟲 Sporozoa 孢子蟲 Ciliates 纖毛蟲 Phylum Sarcomastigophora 變形鞭毛蟲門 Subphylum Mastigophora 鞭毛蟲亞門 Class Zoomastigophorea 動鞭毛蟲綱 Subphylum Sarcodina 變形蟲亞門 Superclass Rhizopoda 根足蟲超綱 Class Lobosea 變形蟲綱 Amoeba Phylum Apicomplexa 頂端複合門亞米巴原蟲 Class Sporozoea 孢子蟲綱 Subclass Coccidia 球蟲亞網 Subclass Piroplasmia 梨槳片亞綱 Phylum Cilophora 纖毛蟲門 Class Kinetofragminophorea 動基裂綱 Subclass Vestibuliferia
Balantidium coli 大腸纖毛蟲 The only ciliate which can parasitize humans, causing balantidiasis Malmsten was the first to recognize the organism in two humans with dysentery in the year 1857. A ciliate normally parasitic in World-wide distribution More commonly found amongest those who keep pigs, especially in warmer climates Areas of high prevalence include regions of Latin America, the Philippines, Papua New Guinea and West Iran, and areas of the Middle East
Morphology of Balantidium coli Ciliates Large oval shaped, 30~300 x 40~70 um Body covered with cilia Foamy cytoplasm Marco- and micronucleus can be seen Cytostome 胞口 Food vacoule 食物泡 Micronucleus 小核 Cytopyge Contractile vacoule 伸縮泡 Macronucleus 大核 Cyst Large spherical, 40~60 um Thick cyst wall composed of 2 layers Macronucleus visible
C P Mi Ma V 20 µm
W 20 µm
Life Cycle of Balantidium coli Cyst ingested EXTERNAL ENVIRONMENT Infective cyst 感染性囊體 Conjugation 接合生殖 Binary fission 二分法分裂 Excyst 脫囊 in small intestine Multiply in colon Encyst Cyst in faeces
Clinical Features Usually symptomless or characterized by intermittent diarrhea and constipation When invade intestinal wall cause inflammation and flask-shaped ulcers Dysentery with blood and mucus Serious complications are rare Intestinal perforation In a survey of 325 waterborne diseases in North America and Europe, Balantidium infections accounted for 0.3% (n=1) of the outbreaks. A comprehensive study of stool samples from 2,000 Aymara Indian children from the Altiplano region of Bolivia found widespread infection with balantidia but a low level of fulminant disease among the children. The overall prevalence of B. coli was 1.2% (range, 1.0 to 5.3%). More than half of the pigs (n=50) in the same communities were infected with balantidia, as determined by examination of stool samples.
Pathology of Balantidiasis Balantidiasis colon ulcers Colon with ulceration and necrosis Flask-shaped ulcers Trophozoites at the base of colonic ulcer EM of trophozoite in clon
Balantidiasis a Amoebiasis c MM MM 500 µm 500 µm b d 50 µm 50 µm
Laboratory Diagnosis Mix small amount of faeces in saline with Dobell's iodine Finding ciliates in dysenteric faecal specimens Large oval shaped, 30~300 x 40~70 um Rapid revolving motility Cilia can be seen Marco- and micronucleus *B. coli ciliates degenerate rapidly in faeces Finding cyst in formed or semiformed faeces Large spherical, 40~60 um Thich walled Macronucleus visible
Metronidazole (Flagyl) a disulfiram drug N CH 3 NO 2 N. CH 2. CH 2. OH Side effects nausea dryness of the mouth perception of metallic taste consequent anorexia intolerance to alcohol tetratogenic in animals Dosage: 2.0 g per day for 7 days; 250 mg, tid for 5 days <2 yrs - 125 mg/day; 2~4 yrs: 250 mg/day; 4~8 yrs: 375 mg/day; 8~2 yrs: 500 mg/day Potential carcinogenic and mutagenic in rodents Not to be used by women during the first three months of pregnancy and newborns during the first six weeks of life
FLAGELLATES 鞭毛蟲 Lumen-Dwelling Flagellates 腔道鞭毛蟲 Intestinal 腸道 Uro-genital 泌尿生殖道 Oral 口腔 Blood & Tissue Flagellates 血液及組織鞭毛蟲
Lumen-Dwelling Flagellates 腔道鞭毛蟲 Pathogenic ( 致病 ) Opportunistic ( 伺機性 ) Commensal ( 共生 ) Intestinal Giardia Lamblia 梨形鞭毛蟲 Chilomastix mesnili 唇形鞭毛蟲 Pentatrichomonas hominis 人腸道鞭毛蟲 Retortamonas intestinalis 腸滴蟲 ( 腸旋滴蟲 ) Enteromonas hominis 恩特若姆那斯鞭毛蟲 Dientamoeba fragilis 雙核阿米巴 Uro-Genital Trichomonas vaginalis 陰道鞭毛蟲 Oral Trichomonas tenax 口腔鞭毛蟲
Giardia lamblia 梨形鞭毛蟲 Vilem Lambl Two hundred years after van Leeuwenhoek had seen Giardia parasites, in 1859, a Czech physician named Vilem Lambl observed Giardia intestinalis in the stools of children with diarrhea, but believed the protazoa to be commensal and not responsible for the pathology. The species was then named Giardia lamblia in his name. The question as to whether giardia was a pathogen or commensal was debated for many decades during the first part of the twentieth century. Giardiasis (Traveller's disease) is particularly common in the tropics and subtropics. In areas where where water suppplies and the enivrnoment become faecally contaminated.
Transmission Faecal-oral route : by the ingestion of cysts in food or water contaminated with faeces containing cysts. G. lamblia cyst ( 囊體 ) 卵圓形長約 8~14 um, 寬約 5~10 um 囊壁呈雙層含有 2 或 4 個核及 2 個軸柱 (axostyle) Remain infective for 1 month at 21 o C Not killed in food or water stored at 4 o C. Resistant to chlorine
cyst trophozoite Cyst excyst 脫囊 in the upper small intestine 十二指腸 to form trophozoites 營養體 G. lamblia trophozoite 扁平呈梨形, 長寬約 10~15 x 6~9 um, 厚約 3 um 兩側對稱, 前端較寬, 腹面凹陷左右兩側各具有一個吸盤 (sucking disk) 蟲體具 8 根鞭毛 (4 側, 2 腹, 2 尾 ) 2 個大型細胞核,
Trophozoits live on surface of villi 絨毛 villi of upper smal intestine G. lamblia trophozoite
Trophozoites attached to duodenal villi 絨毛 Infective cyst excreted in faeces Trophozoites detached and encyst 形成囊體
Note the impression left on the epithelia where a trophozoite has detached (upper left) and the interaction between the ventral disk of the parasite and the brush boarder cells of the intestines (lower right).
Ingestion of cyst Asymptomatic carrier 無症狀帶原者 15% of adults 50% of children incubation period 8 days (1~75 days) prepatent period 9~14 days Acute Giardiasis 急性期 Subacute and chronic Giardiasis 慢性期
Acute Giardiasis First Signs nausea, anorexia, malaise, uneasiness in the upper intestine. low grade fever and chilles Onset acute, explosive, watery, offensive diarrhea. stool frequency 3~8 times a day no blood, pus or mucus in stools flatulence marked abdominal distension vomitimg foul sulfuric belching upper to midepigastric cramps lasts for 3 to 4 days Infection clear sponatneously Change to asymptomatic form Continue for months in acute form Subacute and chronic Giardiasis Acute viral enteritis, Campybacter infection Bacillary dysentery, Food poisoning Acute intestinal amebiasis, Toxic E. coli
Subacute and Chronic Giardiasis periodic, brief episodes of loose foul stools bulky, yellowish, and forthy intestinal gurgling increased abdominal distension alternative steatorrheal 脂肪便 & constipation anorexia, nausea epigastric uneasiness Malsorption of lactose, xylose, vitamin A, B 12 and fats Infection persist for years urticaria lassitude headaches myalgias Infection clear sponatneously
梨形鞭毛蟲症引起之吸收不良及組織切片特徵 小腸功能 組織切片形態 嚴重感染 吸收不良脂肪 D-xylose ( 木醛糖 ) 維他命 A, B 12 乳糖無耐受力 小腸絨毛變厚, 變短, 或萎縮隱窩 (crypt) 變深細胞侵潤增加絨毛間可發現活動體 輕度感染 吸收正常或只有 D-xylose 吸收不良乳糖無耐受力 (Lactose intolerance) 組織切片正常
Jejunal Biopsy from Patients with Giardiasis Crypt 隱窩 No significant symptoms Severe diarrhoea, weight loss and mlabsorption Normal villi Diarrhoea for 1 mth Long standing diarrhoea
Laboratory Diagnosis Stool examination finding cyst in faeces finding motile flagellates in diarrhoeic faeces Enterotest capsule (string) Test for recovery of flagellates Finding flagellates in duodenal aspirates Small bowel biopsy Immunodiagnosis
Enterocapsule (String) Test HEDECO Comapny, Mountain View, CA 94043, USA 4 hrs to overnight Distal half scrapped off onto a slide by gloved fingers Mix with saline Observe under microscope for TROPHOZOITE Nylon line Adult 140 cm Pediatric 90 cm Gelatin capsule
Stool Examination collect at least 3 stool specimens Finding cyst in faeces on alternative days the cysts are passed irregularly. Often large numbers may be present for a few days, followed by fewer numbers for a week or more Finding motile flagellates in acute diarrhoeic faeces Faecal specimens have an offensive smell, usually pale and fatty, often contains mucus Cyst Trophozoite
Examination of diarrhoeic faeces for Giardiasis Specimens: offensive smell, pale and fatty, often contains mucus Concentration:Formol ether concentration technique Formol detergent sedimentation technique Zinc sulphate flotation technique Stain: cyst - eosin or iodine flagellate - Field's rapid stain Stage: mostly cysts and less commonly, motile flagellates
Treatment Metronidazole (Flagyl) 400 mg (adult), 5 mg/kg (children), tid, for 5~7 days or 2~2.5 g once daily for 3 days Tinidazole A single dose of 2 g for adults 30 ~ 35 mg/kg for children Mepacrine 100 mg, tid for 5~7 days Furazolidone 10 mg/kg daily for 5 days (max. 600 mg/day) Albendazole 400 mg daily for 5 days Quinacrine HCl (Atabrine) 0.1g t.i.d for 5 days
Metronidazole (Flagyl) a disulfiram drug N CH 3 NO 2 N. CH 2. CH 2. OH Side effects nausea dryness of the mouth perception of metallic taste consequent anorexia intolerance to alcohol tetratogenic in animals Dosage: 2.0 g per day for 7 days; 250 mg, tid for 5 days <2 yrs - 125 mg/day; 2~4 yrs: 250 mg/day; 4~8 yrs: 375 mg/day; 8~2 yrs: 500 mg/day Potential carcinogenic and mutagenic in rodents Not to be used by women during the first three months of pregnancy and newborns during the first six weeks of life
GIARDIASIS PREVENTION Avoid drinking water from sources associated with outbreaks Water filtration Chlorination is not effective In day cares; wash hands and proper disposing of diapers Hikers and backpackers should be warned to boil or filter water Swimming pools are specially vulnerable
TRICHOMONIASIS 陰道鞭毛蟲症 a sexually transmitted infection (STI) caused by the flagellate Trichomonas vaginalis Worldwide distribution with the highest prevalence in females of sexually active groups
Morphology of T. vaginalis trophozoite 梨形長約 7~23 um ( 平均 13 um), 寬約 5~15 um 前端有 4 根鞭毛第 5 根鞭毛附著於活動體上, 形成波動膜後端有一軸柱突出體外可見一大型細胞核及副基體
蘋果日報 20100208
Transmission Infective form: Trophozoite Person to person by sexual contact Contact with articles contaminated with vaginal discharges T. vaginalis can survival up to five days at 0 o C at optimum condition in pseudocyst ( 假囊體 ) form (moist, ph<4.9) T. vaginalis live in the urogential tract 泌尿生殖道 of both women and men
Atyptical infection: Pulmonary trichomoniasis In newborns T. vaginalis acquired from mother during delivery In adults T. vaginalis acquired by "oral-vaginal" conatct
Clinical Symptoms - Males Trophozoites live in the urethra 尿道 and prostate 前列腺 Usually asymptomatic - Carrier Occasionally cause urethritis ( 尿道炎 ) or prostatitis ( 前列腺炎 ) Urethral discharge is non-purulent
Clinical Symptoms - Females Trophozoites live in the vagina cuase Trichomonad vaginitis About 20% are asymptomatic Onset usually after menstruation Severe vaginal itching or burning About 40% cause acute inflammation of vulva ( 陰部 ) and cervix ( 子宮頸 ) Produce yellow-greeen purulent discharge. Somtimes accompanied by urinary frequency
Pathological Changes about 2/3 of the infected women shows Exo-cervix epithelium increased vascularity edema imflammation Exocervix epithelium Strawberry cervix Endocervical mucosa basal hyperactivity squamous metaplasia Normal Abnormal Vaginal erythema and discharge
Cytoaherence of T. vaginalis to vaginal epithelial cells (VEC) Trichomoniasis is associated with preterm delivery, low birth weight and increased infant mortality. Infection also pre-disposes individuals to HIV/AIDS and cervical cancer. Individuals infected with T. vaginalis have a significantly increased incidence of HIV transmission (Cohen, 2000; Upcroft and Upcroft, 2001).
Diagnosis of Trichomoniasis Clinical presentation ( 臨床症狀 ) Finding trophozoites in wet mounts of vaginal discharges ( 陰道分泌物 ) or urethral discharges ( 尿液, 精液或前列腺液 ) In-vitro culture ( 體外培養 ) of vaginal or urethral discharges in TYI medium
人體寄生鞭毛蟲之形態比較 陰道鞭毛蟲 T. vaginalis 腸道鞭毛蟲 P. hominis 口腔鞭毛蟲 T. tenax 寄生部位波動膜前鞭毛後鞭毛核 陰道, 尿道相當於蟲體 1/3~2/3 4 1, 不游離核膜內染色質粒較細核仁甚小或無 腸道與蟲體等長 3~5 1, 不游離核膜內無染色質粒核仁大而明顯 口腔相當於蟲體 2/3~3/4 4 1, 不游離核膜內有較多染色質粒故染色較深, 無核仁
The Life Cycle of Trichomonas vaginalis Trophozoite Amoeboid Pseudocyst prevention Strawberry cervix Vaginal erythema
Metronidazole (Flagyl) a disulfiram drug N CH 3 NO 2 N. CH 2. CH 2. OH Side effects nausea dryness of the mouth perception of metallic taste consequent anorexia intolerance to alcohol tetratogenic in animals Potential carcinogenic and mutagenic in rodents Not to be used by women during the first three months of pregnancy and newborns during the first six weeks of life
Chilomastix mesnili 唇形鞭毛蟲
Cyst from environment Encystation Multiply by binary fission Excystation Cyst to environment
活動體 大小 :6~20 X 3~10 um 形狀 : 梨形, 前端鈉圓, 未端尖銳 構造 : (1) 胞口位於體前端, 左右兩緣較厚, 呈口唇狀, 向後延伸約佔蟲體一半 (2) 核 : 圓形或卵圓形, 位於蟲體前端 (3) 鞭毛 : 前排 3 根鞭毛 (1 長 2 短 ), 游離於蟲體煎端 後排 1 根較短的鞭毛, 向後伸人胞口另 2 個各發出纖絲一條 (4) 嫘旋溝 : 從體前端的背面開始, 轉入體後端的腹面, 為體表的螟旋狀凹陷 Nucleus 核 Cytostomal flagellum 胞口鞭毛 Cytostome 胞口 囊體 大小 :7~10 X 4~6 um 形狀 : 檸檬形或卵圓形 構造 (1) 囊壁薄, 但前端厚 (2) 核 :1~2 個, (3) 有胞口, 內有鞭毛及纖絲等 Cyst wall 囊壁 核 胞囗
Draft Genome Sequence of the Sexually Transmitted Pathogen Trichomonas vaginalis (Science, 12 Jan 2007) 長庚大學十五日舉行記者會, 宣布與國際合作完成人類陰道鞭毛蟲全基因體定序相關研究成果, 在國際知名學術期刊 科學 (Science) 作為封面 圖為研究計畫主持人邱政洵 ( 左 ) 教授與鄧致剛 ( 右 ) 教授 // 中央社 (2007.1.15)
http://www.nsc.gov.tw/scicircus/ct.asp?xitem=9261&ctnode=1976