Intestinal & Urogenital Flagellates & Ciliates PDF

INTESTINAL & UROGENITAL FLAGELLATES & CILIATES Prof. Dr. Mohamed Kamel UKM Pathogenic Intestinal & Urogenital Flagellates Giardia intestinalis/duodenalis/lamblia Dientamoeba fragilis Trichomonas vaginalis  Non Pathogenic...

INTESTINAL & UROGENITAL FLAGELLATES & CILIATES Prof. Dr. Mohamed Kamel UKM Pathogenic Intestinal & Urogenital Flagellates Giardia intestinalis/duodenalis/lamblia Dientamoeba fragilis Trichomonas vaginalis  Non Pathogenic Intestinal Flagellates Chilomastix mesnili Retortamonas intestinalis Enteromonas hominis Trichomonas hominis Trichomonas tenax Giardia intestinalis/duodenalis /lamblia The infection or disease is called giardiasis Worldwide in distribution but more prevalent in the tropical region where socio enonomy and sanitation is poor  General Widely distributed in the world Infection more serious amongst children compared to adult Most frequent cause of waterborne diarrhea outbreak in USA (30,000 cases/yr) Endemic at the children day care center in US (approx 5-15% infection among children wearing diapers)  cont 200 million cases/year worldwide Epidemic in the wilderness areas) (natural water sources eg. ponds, lakes, stream - harboring the cysts) Human infection may be a zoonosis Giardia also infects animals eg. rodent, deer, cattle, beaver or domestic animals  Giardiasis - Acute/Chronic Diarrhea - Malabsorption Syndrome - Tourist’s Diarrhea Habitat of Giardia - in small intestine esp. duodenum/jejunum It has 2 stages : Trophozoite / cyst Trophozoite · Shape like a pear / smiling face · Face - convex dorsally, ventrally concave with sucking disc · Eyes – 2 nuclei (large karyosome) without peripheral chromatin. Mouth – 2 curved median bodies / parabasal bodies. Axostyle forms by 2 axonemes, divides the flagellate into 2 parts. Size - 10-20 x 5-15um, falling leaf movement · 4 pairs of flagella · Divides by longitudinal binary fission Cyst oval 8-12 x 6-10um · Immature cyst has 2 nuclei, mature has 4 · Median bodies present · Resistant and is the infective form Epidemiology tropical, subtropical, temperate Infects all ages but higher prevalence among children Infection - oro-fecally by ingestion of mature cysts Direct transmission – person to person fecal oral contamination  Indirect – through contaminated water and food Sexual transmission – gayman (oro-anal contact) · Travellers to endemic areas · Zoonosis - beaver, muskrats Pathology · Trophozoite sticks firmly to intestinal mucosa · Resulting in shortening of the mucosal villus, villus atrophy and damage to the intestinal epithelial cells  hipochlorhidria, hipogammaglobulinaemia facilitate infection IgA and IgM have roles in eradication of infection Clinical Manifestation Diarrhea, abdominal pain, cramps, flatulence, malabsorption, weight loss Causes fat malabsorption, fat soluble vitamins, folic acid deficiencies, steatorrhea Asymptomatic carrier is common Diagnosis - Recovery of parasite Feces, duodenojejunal aspirate - Serological tests (not so sensitive) Prevention Potable water supply - filtration system Drink only boiled water(cyst resistant to chlorine) Good sanitation and personal hygiene Safe sexual practice Treatment Metronidazole or tinidazole orally Dientamoeba fragilis · Amoeboflagelat related to Trichomonas, (not having cyst stage). · A commensal in colon but can cause diarrhea, abdominal cramps · Pathogenicity controversial · Only trophozoite stage present · Ameba size 6-12um. · Usually has 2 nuclei, without peripheral chromatin · Karyosome is formed by clusters of 4-6 beadlike chromatin granules.. Transmission by feco oral route Urogenital Flagellate Trichomonas vaginalis  Causes trichomoniasis – infection of genital tract In woman– usually asymptomatic or vulvovaginitis can involve the urethra and exocervix In Man, organism lives in urethra, prostate and seminal vesicles Morphology - exists as trophozoite only - round/oval 10-15 X 7-10um, - jerky motility, 4 ant flagella - undulating membrane extending to half the length of body  Life Cycle Trophozoite lives on vaginal mucosal membrane but does not invade the mucosa Feeds on bacteria & leucocyte Divides by longitudinal binary fission Epidemiology Distribution - Globally,180 mil cases/yr - 5-6 mil case in USA - Correlated with the number of sexual partners - 7-32% reported from VD clinic - 50-75% among sex workers Transmission - Sexually - Infection alongside with other STDs - Neonatal infection may occur during the process of birth Pathology - Infection of vaginal mucosa causes acute inflammation - Tv can destroy cells directly in contact with the trophozoite  It however does not invade the mucosa If the vaginal pH is more basic (alkaline), reproduction is better (normal pH vagina : 3.8 - 4.2) Tv prefers pH around 5.5 Clinical Manifestation Woman 1. asymptomatic Vaginitis - in about 60% cases - quite common  2. Symptomatic Vulvovaginitis - acute or chronic infection - pruritus vulva-vagina, - vaginal odour, dyspareunia, - vaginal dischrage (yellow/ green- frothy) 3. Urethritis (NGU) - dysuria in 25% of cases In Man - Usually Asymptomatic - Self limited - Urethritis, prostatitis, epididymitis - dysuria Neonatal Infection - occur during process of birth. - Asymptomatic or vaginitis Diagnosis - Recovery of protozoa microscopically or by culture - Specimens include vaginal/urethral discharge, urine  Culture is better (up to 95% detection) Papanicolaou (Pap) smear – Not very sensitive, only 50% detection Polymerase chain reaction (nucleic acid amplification) – Not widely available, but very sensitive & specific Prevention & Control - avoid risky behaviour eg. promisquity - Safe sex, Condoms - Infection does not confer immunity Treatment - Both symptomatic male and female must be treated - Sexual partners must be treated as well. - Metronidazole  Non Pathogenic Flagellates 1. Chilomastix mesnili Mainly in colon, can also be found in small intestine Trophozoite Pear shape 10-15um, stiff rotary movements 3 anterior flagella, 1 posterior flagellum Single nucleus, large karyosome Prominent cytostome Cysts Lemon shape 6-10um Single nucleus, hyaline anterior prominence 2. Retortamonas intestinalis - rarely seen Trophozoite Small 4-9um, 1 anterior and 1 posterior flagella 1 nucleus, jerky movements Cyst 4-9um, 1 nucleus 3. Enteromonas hominis - rarely seen Trophozoite 4-10um, jerky movements 3 ant flagella, 1 post flagella Cyst 4-10um, 1-4 nuclei 4. Trichomonas hominis - Only exists as trophozoite - Pear shape 8-20um - Jerky movements, 4 ant flagella, 1 post flagellum - Undulating membrane continues posteriorly ending with a free trailing flagellum 5. Trichomonas tenax - Trophozoite only - Habitat in oral cavity esp poor dental hygiene - Transmission : through droplet, kissing, eating utensil - Size 6-10um  CILIATE Balantidium coli The largest protozoa infecting human causes balantidiasis and superficial ulcer (diarrheal disease and dysentery) Habitat in the colon A zoonosis  Epidemiology Found in tropical, sub tropical and temperate regions Pig is the main reservoir host while monkeys and rodents also get infected Is a Zoonosis Cases had been reported in Malaysia amongst the Orang Asli, Chinese and Indian Contamination of food/water with feces containing the cysts of the parasite  Morphology 2 stages in life cycle; trophozoites and cyst Trophozoite Largest protozoan trophozoite, oval, size 50-100 um x 40-70 um. Cilia surrounds the whole body Rapidly motile using cilia Anterior end is narrower and has cytostome (mouth like structure).  Has 2 nuclei - the larger macronucleus, kidney shaped and the much smaller micronucleus Cytoplasm contains many food granules and vacuoles. Contractile vacuole opens posteriorly through an opening called the cytopig ( anus like structure)  Cyst Largest protozoan cyst, round in shape about 50-70 um. Cilia may be seen inside the cyst wall. Food and contractile vacuoles can be seen.  Life Cycle Direct transmission by ingestion of cysts. Cysts contaminating food or water Source of infection are the pigs and infected person Reproduction by binary fission and also sexually by conjugation.  Patology & Clinical Manifestation Usually asymptomatic but can also cause superficial ulcer of the colonic mucosa Diarrhea, dysentery, abdominal pain and cramps  Diagnosis, Treatment & Prevention Discovery of parasites in feces (trophozoite or cyst) Treatment with Nitroimidazole (metronidazole) or Tetracycline Good personal hygiene, food hygiene and good sanitation Health education