PRELIM LEC 3: CILIATES AND FLAGELLATES Flashcards
● Causes BALANTIDIASIS
● LARGEST PROTOZOAN
PARASITE affecting humans
● ONLY CILIATE capable of causing
DISEASE to HUMANS
● Normal host: PIGS
● HUMANS - accidental host
Balantidium Coli
INFECTIVE STAGE OF Balantidium
Coli
Balantidium Coli MATURE CYST
Balantidium Coli will inhabits the ______________
LARGE INTESTINE
MOT of Balantidium Coli
ingestion of contaminated food or water
Balantidium Coli TROPHOZOITE motility
football/throwball motility
● use for movement/locomotion
● Longitudinal pattern cilia
● CYTOSTOME - food acquisition
(mouth of the parasite)
● CYTOPYGE - waste excretion (anus
of the parasite)
● 2 nuclei
○ MACRONUCLEUS: bean -
shaped (vegetation)
○ MICRONUCLEUS - round -
shaped (reproduction)
● 2 contractile vacuoles
● Mucocysts - located beneath the
membrane
● football/throwball motility
Balantidium Coli TROPHOZOITE
● spherical /ovoid
● Covered with thick cell walls or
refractive double wall
Balantidium Coli CYST
BALANTIDIASIS
● Intestinal Ulceration is caused by __________
- ulcer is ROUND BASE and WIDE NECK
HYALURONIDASE
3 forms of BALANTIDIASIS
- DO NOT PRESENT WITH DIARRHEA or dysentery, but may serve as a parasite reservoir in the community.
ASYMPTOMATIC CARRIER
SUDDEN ONSET OF BALANTIDIASIS; involves diarrhea with bloody mucoid stools
Fulminant or balantidial dysentery
wherein diarrhea is alternate with constipation and results in abdominal pain and anemia.
Chronic form
DIAGNOSTIC TESTS OF Balantidium coli
- Direct Fecal Smear (DFS) & Concentration Techniques - (sedimentation or flotation) : microscopic demonstration of Trophozoites and Cysts
- Lesions from sigmoidoscopy
- bronchoalveolar washings
TREATMENTS
contraindicated in children <8 years of age
ADULTS & OLDER CHILDREN: 500 mg or 40 mg/kg/dose divided in 4 doses for 10 days
TETRACYCLINE
contraindicated in early pregnancy
Metronidazole
- MOST COMMON cause of DIARRHEA WORLDWIDE
- Known to cause epidemic and endemic diarrhea
- Can grow and live in duodenum, jejunum and upper ileum of intestine
- Causes GIARDIASIS
- Only protozoan that is BILATERALLY SIMILAR
- Other terms: Giardia intestinalis and Giardia lamblia
Giardia duodenalis
1st discovered by _________in his own stool
Anton van Leeuwenhoek
1st described by Lambl in 1859 who called it?
Cercomonas intestinalis
It was later renamed Giardia lamblia by ________ in 1915.
Stiles
DIAGNOSTIC STAGE: cyst and trophozoite in stool
● INFECTIE STAGE: MATURE CYST
○ Can survive in cold water
○ Responsible for the transmission of
Giardiasis
○ MOT: ingestion of contaminated food or water and fecal - oral route (on the
hands)
○ will multiply by longitudinal binary fission
○ Note: Each cyst produces 2
trophozoite
Giardia duodenalis
● Pyriform or teardrop shaped
● Nucleus
○ 2 ovoidal nuclei each with large karyosome “old man with eyeglasses”
● Dorsal: convex
● Ventral: concave with sucking disk
(large adhesive disk that is used by
the parasite to attach in the
intestine.)
● Axostyle (medial line)
○ Can be seen if stool and smear are fresh
● 4 pairs of flagella
○ Floating leaf-like motility
Giardia duodenalis TROPHOZOITE
● Nucleus
○ Immature: 2
○ Mature: 4
○ Shape: Ovoid
● 1 mature cyst give rise to 2
trophozoite
○ If the cyst is immature, flagella is retracted to the axonemes
○ if it transforms to trophozoite, flagella will come out.
Giardia duodenalis CYST
CLINICAL MANIFESTATION
- Maximal at body temperature and stable at a pH of 7.8 - 8.2
- Production of lectin
- Decreased maltase and sucrase activities
- Rearrange the cytoskeleton in human colonic and duodenal monolayers
- Disrupt the cellular tight junctions and increase epithelial permeability
DIAGNOSIS of Giardia duodenalis
- PARASITIC DIAGNOSIS
Specimen: Stool, duodeno-jejunal Aspirates - Stool Microscopy
- Direct Wet Mount Examination
- Concentration Techniques (FECT,
- ENTERO - TEST/STRING TEST
- Immunochromatographic assays - detect CWP1(Cyst Wall Protein 1)
TREATMENT
METRONIDAZOLE - oral, 250 mg 3x a
day for 5-7 days
alternative drugs of Giardia lamblia
TINIDAZOLE
FURAZOLIDONE
ALBENDAZOLE
- MOT: sexually transmitted
- Habitat: Genitalia/Gut
- Women - in vagina but may ascend as far as the renal pelvis.
- Parasite can be isolated from the urethra, prostate, and less frequently, in the epididymis in men.
trophozoites multiply by binary fission, - - DOES NOT HAVE CYST FORM & trophozoite cannot live or survive well in external environment
transferred passively from person to person - Usual MOT: sexual intercourse.
Trichomonas vaginalis (Ping - Pong’s Disease)
DIAGNOSTIC STAGE: trophozoite
INFECTIVE STAGE: Trichomonas vaginaliS TROPHOZOITE
- Multiply by ____________
LONGITUDINAL BINARY FISSION
● Pyriform shape
● Single nucleus
● Undulating membrane: 1⁄2 of the body
○ JERKY MOTILITY
● Median axostyle
● 5 flagella
Trichomonas vaginalis TROPHOZOITE
CLINICAL MANIFESTATION
- Speculum examination: ____________(due to the hemorrhage of genitals)
STRAWBERRY CERVIX
- Trichomonas infection in males may be latent and essentially asymptomatic.
___________: most common complication
PROSTATITIS
TREATMENTS
Metronidazole & Tinidazole
HABITAT: intestines
SIZE: 7-13 um
NUCLEUS: ovoidal
UNDULATING MEMBRANE: as long as the body
INCLUSION BODIES: none
- detected to differentiate from the Trichomonas vaginalis
- MOT: fecal contamination of food
and water
Trichomonas hominis
HABITAT: oral cavity
SIZE: 5-12 um
NUCLEUS: rounded
UNDULATING MEMBRANE: 2/3 of the body
INCLUSION BODIES: none
- MOT: Kissing, droplets from the mouth, sharing of contaminated dishes and drinking glasses.
- Can be a commensal of human mouth
Trichomonas tenax
HABITAT: gut/genitalia
SIZE: 7-23 um
NUCLEUS: ovoidal
UNDULATING MEMBRANE: 1/2 of the body
INCLUSION BODIES: siderophil granules
Trichomonas vaginalis
● Habitat: cecal region of the large intestine
● MOT: ingestion of cysts in food and
drinks
● HARMLESS COMMENSAL PARASITE
● Can be diagnosed with microscopic
examinations of feces
● No treatment is indicated
Chilomastix mesnili
○ Asymmetrically pear - shaped
○ Boring and spiral forward
movement
○ 3 anterior free flagella and 1
within the prominent cytostome
Chilomastix mesnili TROPHOZOITE
○ Pear or lemon-shaped
○ Hematoxylin and eosin: single large vestibular nucleus, cytostome and fibril on either side of the cytostome
Chilomastix mesnili CYST
