Transcript INTESTINAL SYSTEM PROTOZOA 1,30053.04 MB

GASTROINTESTINAL SYSTEM
PROTOZOA -I-
Entamoeba histolytica
Giardia lamblia
Entamoeba coli
Doç.Dr.Hrisi BAHAR
Gastrointestinal system
protozoon
Entamoeba histolytica
INTESTINAL PROTOZOA
• Pathogenic
• Commensal
• Entamoeba
histolytica
• Entamoeba hartmani
• Entamoeba dispar
• Balantidium coli
• Giardia lamblia
• Dientamoeba fragilis
• Cryptosporidium
parvum
• Enterocytozoon
bieneusi
• Septata intestinalis
• Cyclospora
cayetanensis
• Isospora belli
• Entamoeba coli
•
•
•
•
•
Endolimax nana
Iodamoeba bütschlii
Chilomastix mesnili
Trichomonas hominis
Blastocystis hominis
Entamoeba histolytica
(amoebiasis)
► Organism:Entamoeba histolytica
► At Risk : Anyone worldwide
► Humans Infected: 50 million
cases of invasive disease/year
►Disease Outcome :100,000
deaths/year
► Available Drugs :Dose limiting side
effects .
Entamoeba histolytica
(amoebiasis)
Morphologic forms:
1- Active trophozoit form
*Cytoplasm:(2/3endoplasm and
1/3 ectoplasm)
* Nucleus: circle with karyosome
* Replication stage 2-4 nucleus
Entamoeba histolytica
(amoebiasis)
Active trophozoit form
Trophozoit form
Entamoeba histolytica
(amoebiasis)
2-Precystic form:
*Intermediate stage
*Low motility
*Untrue morphologic stage of
parasites
*shape: oval or circle
Entamoeba histolytica
(amoebiasis)
Precystic form
Entamoeba histolytica
(amoebiasis)
3-Cystic form:
*Stable and non motile
*Small and large cysts
*Primary cyst with -1- nucleus
*In replication stage 2-4 nucleus
*Karyosome,, chromatoide body
and glycogen in nucleus
Entamoeba histolytica
(amoebiasis)
Cystic form
Entamoeba histolytica
(amoebiasis)
Replication stage of cyst
Entamoeba histolytica cystic forms
Entamoeba histolytica
(amoebiasis)
Stability
*Trophozoit form: unstable
*Cystic form: stable in 20ºC for 3
days and In 45 ºC for 30 min
* Cystic form also stable against
low concentration of CL and
HCL
Entamoeba histolytica
(amoebiasis)
Transmission
*It is transmitted by cystic form*
☻ Direct transmission
With contaminated hands
☻ Indirect transmision
With contaminated food , water
and arthropods.
Life cycle of Entamoeba histolytica
Entamoeba histolytica
(amoebiasis)
Pathogenesis
► Cases acute dysentery
► Chronic stage: occur intestinal
ulcer,inflammation and necrosis
with proteolytic enzyme
► Heavy infection: occur intestine
scleroses ,hypertrophy and
perforation
► Metastases: to liver and brain…
Entamoeba histolytica
(amoebiasis)
Intestinal ameobiasis
●Incubation period is 8 days or several month
● Acute stage: diarrhea with epithelium but
without blood, and abdominal pine , loss
of weight , flatulence and constipation.
● Sever infection : 10-20/day , diarrhea with
blood , abdominal pine (colon)dehydration and
fever.
Entamoeba histolytica
(amoebiasis)
Extra intestinal amoebiais
► Spread of intestinal amoeba
from blood to liver ,
spleen,brain and lung.
► Direct extra intestinal
amoebiasis (without intestinal
infection)
Entamoeba histolytica
(amoebiasis)
Hepatit Amoebiasis
►Causes liver abscess
►Single abscess, different
size , at the right lob of the
liver.
Entamoeba histolytica
(amoebiasis)
Hepatic Amoebiasis
►Symptoms: liver pine , fever right
hypochondrium pain,rarely diarrhea
►Transmit to pleura, peritone and
pericardial area…..dead.
Entamoeba histolytica
(amoebiasis)
Hepatic Amoebiasis
AMOEBIC LIVER ABSCESS
Diagnosis
*Ultrasound
*Raised WBC
*Serology
*Aspirate microscopy
*Response to metronidazole 750 t.i.d.
Entamoeba histolytica
AMOEBIC LIVER ABSCESS
Entamoeba histolytica
(amoebiasis)
Pulmonary Amoebiasis
► 1- Direct primary infection
(blood circulation)
► 2- secondary infection: after
liver amoebiasis at the right
pulmonary ..
Cases are with: single or
several abscess
Entamoeba histolytica
(amoebiasis)
Cerebral Amoebiasis
► Occur from complication of
liver and pulmonary amoebiasis..
► Cases are with single or
several abscess
Entamoeba histolytica
(amoebiasis
Spleen and Cutaneous
Amoebiasis
► Spleen abscess always seem
with liver amoebiasis.
► Cutaneous amoebiasis seem
in perianal site.
Entamoeba histolytica
(amoebiasis
Diagnosis
► Detection of trophozoit and
cystic form of parasites in fresh stool.
► After 30min trophozoit form will
destroy.
► Extra intestinal amoebiasis:
detection of parasite cysts by lugol
stain of infected tissue.
Entamoeba histolytica
(amoebiasis
trophozoit
Direct microscopy :
Detection of trophozoit and cystic form of parasites in
fresh stool.
Entamoeba histolytica
(amoebiasis
Treatment
► Metronidazole 750mg +
diloxanide furoate 500mg X 3 ..
10 days..
► Metronidazole + Iodoquinol
650mg X 3 .. 21 days
► Metronidazole +tetracycline
250mg X 4 .. 10 days
Entamoeba histolytica
(amoebiasis
OR
► Chloroquine 500mg X 1 ..
7days (iiver amoebiasis)
0R
► Paromycine 250mg//kg X 3 ..
7days
Gastrointestinal system protozoon
Entamoeba coli
Entamoeba coli
► Entamoeba coli is a nonpathogenic species of
Entamoeba that frequently
exists as a commensal
parasite in the human
gastrointestinal tract
especially in the colon.
Entamoeba coli
► Clinically, E. coli (not to be
confused with the
bacterium Escherichia coli)
is important in medicine
because it can be
confused during
microscopic examination
of stained stool specimens
with the pathogenic
Entamoeba histolytica
Entamoeba coli
► The presence of E.coli does’nt
need treatment treatment as it
is considered harmless.
► However it should be noted
that when a person becomes
infected with this benign
entamoeba, other pathogenic
organisms may have been
introduced as well, and these
other pathogens might cause
infection or illness.
Entamoeba coli
► The identification of intestinal
amoebae depends on the size
and shape of trophozoites and
cysts and on number of nuclei
and aspect of karyosome and
chromatin.
Entamoeba coli
► Entamoeba coli trophozoites
measure 20-30 µm and have
a vescicolous nucleus with a
large eccentric karyosome
and an irregulary distributed
peripheral chromatin.
The cytoplasm is vacuolated
containing bacteria and yeast.
Entamoeba coli
Trophozoite Entamoeba coli Serum physiologic 400X
► Entamoeba coli trophozoites
Trophozoite Entamoeba coli Lugol 400X
Entamoeba coli
►
► E.coli cysts are spherical and
measure 14-30 µm (usually 15-20).
► Mature cysts have 8 nuclei with a
large karyosome (central or
eccentric) and an irregular
(sometimes regular) chromatin.
► The nuclei can be numerated
with careful focusing.
Entamoeba coli
► While this differentiation is
typically done by visual
examination of the
parasitic cysts via light
microscopy, new methods
using molecular biology
techniques have been
developed also.
Entamoeba coli
►
E.coli cysts
Life cycle of E.coli
Life cycle of E.coli
Entamoeba coli
► Cysts and trophosoits of
E.coli are larger then
E.histolytica.
► E.coli is the only species in
the genus encountered in
humans with more then
four nuclei in the cyst
stage.
Entamoeba coli
► Cysts and trophosoits of
E.coli are larger then
E.histolytica.
► E.coli is found in the mouth
between the gingival
pockets.
Gastrointestinal system
protozoon
Giardia lamblia
(Giardia intestinalis)
Giardia lamblia
► It is an intestinal
flagellate
► Lives in duodenum
and jejunum
► Cause “Giardiasis”
Giardia lamblia
► Human pathogen: G. lamblia or G. intestinalis or G.
duodenalis,
► Two life stages: trophozoite and cyst.
HISTORY
► First observed 1681
by Anthony van
Leeuwenhoek
Giardia lamblia
► First observed 1681 by Anthony
van Leeuwenhoek
► Described ~200 years later by
Vilem Lambl
► First cultured in 1960’s
► Confirmed pathogen 1970’s
► One of most common intestinal
parasites
► Causes Giardiasis (beaver fever)
►Geographic region with poor
water sanitation
Giardia lamblia
► Species details
– Single-celled protist
– 5 species of Giardia
► G. intestinalis/lamblia
• G. muris in rodents, birds,
reptiles
• G. agilis in amphibians
• G. ardae in great blue heron
• G. psittaci in budgerigar
Giardia lamblia
► Morphology
Cyst
www.tulane.edu
► Infective stage in the
environment,
► Persist in cold water up to
several months
► Egg-shaped, 8-14µm by 7-10µm
► Organelle duplication w/out
cytokinesis results
*in four nuclei (Nu)
*four median bodies (MB)
*four axonemes (Ax)
Giardia lamblia
► Morphology Trophozoite
www.med-chem.com
► Cannot survive in the
environment
► Motile 4 pairs of flagella
► Pear shaped, bilaterally
symmetrical
► Relatively flattened, 10-12µm
long
► 5-7µm wide with a large
sucking disk on the anterior
ventral side
► Two nuclei
Giardia lamblia
- Life cycle -
2 trophozoites
released per cyst
Multiply by binary
fission every 12 h
Sucking disc used
for attachment
Cyst forms in
transit to colon
Giardia lamblia
Clinical Symptoms and
Pathogenesis
► Ingested cysts excyst in
response to stomach acidity.
► Attach (via their sucking disk) to
microvilli of epithelium in small
intestine, causing epithelial
damage and interfering with gut
transport processes.
Giardia lamblia
Clinical Symptoms and
Pathogenesis
►Epithelial mucus is thinned,
lymphocytes and other inflammatory
cells infiltrate, physical blocking of
absorption may occur, and
enterobacteria may proliferate, causing
more epithelial damage.
►Distention and flatulence can occur.
Giardia lamblia
Clinical Symptoms and
Pathogenesis
► Symptoms include profuse and watery
to semisolid, greasy, bulky and foulsmelling diarrhea; abdominal cramps;
nausea; vomiting; anorexia; low-grade
fever and flu-like headache. General
malaise, weakness, weight loss.
Giardia lamblia
► Symptoms more likely in children and
immunosuppressed adults than in
healthy adults.
► Infectous dose is low (about 10 cysts;
possibly less).
► Incubation period from 7-11 days.
Giardia lamblia
► Duration of illness varies: few days
to months.
►Infection may resolve
spontaneously. often, subchronic
stage develops with mild to
moderate symptoms occurring
periodically.
Giardia lamblia
Epidemiology
► Many animals are major reservoirs:
dogs, mice, horses, sheep….
► Contamination is by “Fecal-oral route”
► Transmission by contaminated water
and food is common
► Transmission is generally in day-care centers,
with poor hygiene and sanitation.
Giardia lamblia
Epidemiology
► Levels in sewage are estimated in the
range of 3,000 to 30,000 per liter.
► Animal-to-human transmission occurs,
but pathogenicity and virulence of nonhuman sources for humans is still
uncertain.
► Strain differences documented both
antigenically and genetically.
Giardia lamblia.“Diagnosis”
► Diagnosis is by
microbiological examination of
stool samples to check for the
parasite.
► Because Giardia can be
difficult to diagnose, the patient
will ask to submit multiple stool
specimens collected over a
few days.
G.lamblia cysts stained by metilen blue
• intestinalis trophozoite in a
wet mount stained with
iodine.
G.lamblia trophozoite in a wet mount stained
with iodine.
Giardia lamblia :Diagnosis
► Microscopic detection based on finding
distinctive trophs. or cysts in stools, with our
without dye staining or immunofluorescent
(fluorescent antibody) staining.
► Newer clinical diagnostic detection
by enzyme immunoassay (EIA; ELISA).
►Molecular detection by PCR is now
being used for detection and characterization.
Giardia lamblia
Visualization methods
► Laser scanning cytometry
► Immunofluorescent antibodies
(Giardia –specific) for enumeration
► Differential interference contrast
(DIC) for confirmation4,6-diamidino 2
phenyl-indole dihydrochloride (DAPI)
for viability
► Propidium iodide (PI) for nonviability
Giardia lamblia
Electron microscopy pictures
Environmental Control of Giardia
► Water: physical and chemical treatment
(coagulation-flocculation, sedimentation,
filtration and disinfection) will reduce
Giardia
►Relatively resistant to chemical
desinfection
but relatively sensitive to physical
disinfection by UV radiation or heat.
► Pasteurization and thermal treatments is
effective for foods
Giardia lamblia
Protection from Giardiasis
► Washing hands
thoroughly with soap and
water.
► Not drinking untreated
water or not use ice made
from untreated water .
► Washing all food that is
to be eaten raw by
uncontaminated water..
Giardia lamblia
Treatment
► Quinacrine HCl
,Metronidazole (Flagyl) and
Furazolidone (Furoxone).
► Oral Quinicrine HCl cures
about 90% of infections.
► Probiotics could help the
treatment
Giardia lamblia
► Giardia can infect all people
,young
children and pregnant women .
► Rapid loss of fluids from
diarrhea can be especially
life threatening .
► Fluid replacement is an
important part of the treatment