Opportunistic protozoan infections of the GIT Flashcards
Opportunistic protozoan infections of the GIT
Affects mainly the immuno_________
Parasitic infections of the GIT is one of the highest causes of morbidity and mortality among _____ infected individuals
OIPs which usually occurs when CD4+ T cell count is __________ cells/mm
Most common symptom is _______
compromised
HIV
below 200
diarrhoea
Cryptosporidium species
Minute _______ in the subphyllum ______
(Obligate or facultative?) tissue parasite with sexual and asexual life cycle
Associated with ________ in a variety of domestic animals like calves,pigs and chicken
In humans iit is usually associated with __________
coccidian; sporozoa
sporozoa; enterocolitis
HIV infection
Cryptosporidium species: Epidemiology
The organisms are widespread and probably infect (asymptomatically or symptomatically?) a significant proportion of the human population.
The incubation period for cryptosporidiosis is from ____ to ——— and the disease is acquired from infected animal or human feces or from faecally contaminated food or water
asymptomatically
1 to 12 days
Cryptosporidium species: Epidemiology
Risk factors include
– Extremes of ____
– Immuno_______
– Close contact with _________
age
compromised
infected animals
Oocysts of Cryptosporidium species are eliminated by chlorination
T/F
F
Oocysts of Cryptosporidium species are not eliminated by chlorination and may persist after water treatment
Life cycle of Cryptosporidium species
When ______ in contaminated foods and water are ingested (as few as ___ organisms can initiate an infection)
________ ———- and invade intestinal cells and the parasites multiply ______ within the ______ portion of the intestinal cells
are released, and _________ to begin a new cycle.
They also reproduce sexually, forming __________ and ____________ that fuse and develop into the _______.
oocysts; 30
Sporozoites excyst
asexually; apical
infect other intestinal cells
male microgamonts and female macrogamonts
oocysts
Life cycle of Cryptosporidium species
Parasite has the ability to complete its life cycle, including the sexual phase, within the same individual
T/F
T
Cryptosporidium species : Pathogenesis
Cryptosporidium inhabits the _________ of ____________ of the gastrointestinal tract, especially the surface of _____ of the _______________
______ attach to the brush border of the epithelial cells with loss or degeneration of the ______ at the attachment zone
Loss of ________ = impaired ______,_______ that make up the clinical syndrome
Cryptosporidium Infections have also been found in other organs, including other digestive tract organs and the _____.
brush border of mucosal epithelial cells
villi; lower small intestine
Oocyst; microvilli
microvilli; digestion, malabsorption
lungs
Cryptosporidium species: clinical feature
The prominent clinical feature of cryptosporidiosis is ________-like _____ or ______ diarrhea
Persistent ______ with varying degrees of ______,________, and __________
cholera
watery or mocous
gastroenteritis
vomiting, malabsorption and low grade fever
Cryptosporidium species: clinical feature
(mild or severe?) and ________ ( __________ ) in normal persons
but may be severe and prolonged ( _______) in immunocompromised or very young or old individuals
Mild ; self-limited
1–2 weeks
months
Oocysts of Cryptosporidium species
____ μm
_____ to _________ shape
stain ______ in stool samples stained with ___________ stain
4–6
ovoid to spherical
pink; an acid-fast
Oocysts of Cryptosporidium species
Highly _______ on wet mount
__________ may be observed internally or with phase contrast microscope
May contain up to ___ slender ___ shaped sporozoite
refractile
Small granules
4; bow
Diagnosis of Cryptosporidium species
Detection of _____ in __________
_____ concentration techniques + a modified ____________ .
__________ microscopy with _______ staining.
detection of fecal ______ using immunological techniques like ______
Molecular - PCR
Oocysts; fresh stool samples.
Stool; acidfast stain
fluorescent; auramine
antigen; ELISA
Treatment of Cryptosporidium species
List 3
paramomycin
Azithromycin
Nitazoxanide
CYCLOSPORA AND CYSTOISOSPORA (ISOSPORA) species
Both are only opportunistic pathogens in immunocompromised hosts
T/F
F
Both are opportunistic pathogens in immunocompromised hosts but also infect noncompromised patients.
CYCLOSPORA AND CYSTOISOSPORA (ISOSPORA) species
Cyclospora: distribution is _____ and is endemic in _______ areas, with outbreaks in ________ areas.
Cystoisospora: occurrence is primarily in _______________ climes, especially South America, Africa, and Southeast Asia.
________ and _________ are primary sources.
worldwide; developing
developed
tropical and subtropical
Contaminated food and water
Oocysts of CYCLOSPORA AND CYSTOISOSPORA (ISOSPORA) species can survive in environment for _______ but must _______ to become infective.
months
sporulate
Life Cycle of Cystoisospora( Isospora belli)
(Mature or Immature?) Cystoisospora oocysts, each containing a ______________, are excreted in the stool of infected hosts.
Oocysts can remain viable in the environment for _______.
_______ in the environment is required before oocysts become infectious
The _________ divides in two, and each newly formed _______ subsequently matures into a _______.
Immature
single sporoblast
months
Sporulation
single sporoblast
sporoblast
sporocyst
Life Cycle of Cystoisospora( Isospora belli)
The resulting infective ______ ————- contains ________, each with ________.
Ingestion of ____________ results in the release of ______ in the ____________ which may develop into _____, with subsequent ________ reproduction occurring within enterocytes;
over time, _____ reproduction follows, resulting in the development and passage of (mature or immature?) ________ ———- in feces.
Rarely, some sporozoites can _________________where they may remain _________ and later give rise to _______ disease.
elliptical oocyst
two sporocysts; four sporozoites
sporulated oocysts; sporozoites
proximal small intestine; merozoites; asexual
sexual; immature, unsporulated oocysts
migrate out of the intestine to various
tissues
dormant as cysts; extraintestinal
Diagnosis of CYCLOSPORA AND CYSTOISOSPORA (ISOSPORA) species
Acute or chronic ______ occurs with other constitutional and gastrointestinal symptoms.
______ in stool may be visualized using ______________ stain.
_______ stool examinations may be required
diarrhea
Oocysts
modified acid-fast
Multiple
Treatment of CYCLOSPORA AND CYSTOISOSPORA (ISOSPORA) species
____________
or
___________
Trimethoprim-sulfamethoxazole
ciprofloxacin
Microsporidia
are (obligate or facultative?) ___karyotic _____cellular pathogens related to _____
contains at least ______ species
distributed into more than _____ genera.
obligate eukaryotic intracellular
fungi; 1200
190
Microsporidia
Several different genera and species of microsporidia cause disease in humans
Microsporidiosis occurs in both immunocompromised and immune-competent hosts.
T/F
T
T
Microsporidia
can be transmitted by __________ and are likely ———-
__________ or ____________ are the most common presenting manifestations of infection, but infection can occur in any organ system.
food or water ; zoonotic
Diarrhea or keratoconjunctivitis
Microsporidia
Diagnosis can be made by finding characteristic _____ in body fluids
_______________________ of the microsporidia causing an infection can be done using ____ examination or molecular techniques.
Patients with diarrhea or keratoconjunctivitis should have _____ examined to look for disseminated infection.
Species-specific diagnosis is useful for guiding treatment.
spores
Definitive identification
ultrastructural
urine
Treatment of Microsporidia
Systemic ________ and fumagillin
____ in HIV patients
albendazole
ART
Phylum Ciliophora
are group of ______ characterized by _____ like structure called ______ which is important in movement and nutrition
•Possess _____
protozoa; head; cilium
cilia
Phylum Ciliophora
• Possess cilia- _______ or ________ organelles during some part of their life cycle
• Most species have 2 kinds of nuclei: _______ and _________
simple cilia or compound ciliary
macronuclei and micronuclei
Phylum Ciliophora
• Some members of the phylum engage in sexual reproduction, involving _______,________, and ________
• Most ciliates are _______; however, a few groups are ________ or ________
conjugation, autogamy, and ctyogamy
free-living
commensals or parasitic
Family Balantidiidae, which includes only one genus and species (__________) are found in the _______ of _____ and some vertebrates, including mammals
Balantidium coli
intestinal tract; arthropods
Family Balantidiidae
• Pathogens of ______,_______,______
•______ are non-pathogenic carrier
•Mostly infect at ———-,————
•Balantidium coli cause ________,_________
humans, dogs and monkeys
Swine
Cecum, large intestine
Balantidiosis Ciliary dysentery
Family Balantidiidae
B.coli :- is the ______ intestinal protozoa that effect human and can be seen _____scopically
Balantidiosis regarded as a ______ disease
largest
macro
zoonotic
B.coli : Epidemiology
_________ distribution but is most often found in _____ regions
Although B. coli is found in many mammals, ________ and ________ are considered to be the main reservoir for human infection with prevalence rates of ___% to ___%.
worldwide; tropicale
domestic and wild pigs
40; 100
B.coli: Epidemiology
It is not a common human disease
the prevalence is usually _____%
higher rates have been reported among individuals in hyperendemic areas and residential institutions.
____ is transmitted (fecal oral)
less than 1
Cyst
B.coli: epidemiology
Human infection most often results from the ingestion of produce or water contaminated with ________ or from _________.
______ transmission can also occur.
However, humans are generally (sensitive or resistant?) to infection, and _________ seem to be risk factors for disease
pig excrement; handling of the animal
Person-to-person
resistant
poor nutrition and underlying debility
Morphology :- the parasite is observed in two stages only which
are :-
A) trophozoite :-
(Smal or Large?) size , the _____ trophozoite usually measures 30 to 150 μm in length and 25 to 120 μm in width but may reach 200 μm in length.
•the invasive stage .
covered by _____ & the (anterior or posterior?) end are longer than the (anterior or posterior?) end .
in the anterior end there is mouth called _______ .
Large ; oval
cilia; anterior ; posterior
cytosome
Morphology :- the parasite is observed in two stages only which
are :-
trophozoite :-
the internal structures :-
have ______ nuclei , the _______ (the large one) & ________ (the small one ) .
the macronucleus is _______ or _——— in shape .
the micronucleus is _____ ——- shape located in the ______ of macronucleus .
have two secretory contractile vacuoles . numerous food vacuoles .
two; macronucleus; micronucleus
kidney or bean
small spherical ; concavity
Balantudium coli
Morphology :- the parasite is observed in two stages only which
are :-
B- Cyst :-
___ to _____ μm in diameter
typically ______ in shape .
surrounded by (thin or thick?) wall (one or two layers ) by ______ in small intestine to protect the parasite from the host .
contain the _______ and ________ which are visible in the cyst .
the cilia are _______ , only the ______ may present .
40 to 60; spherical
Thick ; encystation
macronucleus and contractile vacuoles
undetectable; roots
B.Coli
1- Asexual type by _______ .
2- Sexual type by ________ .
binary fission
conjugation
B.coli
Life cycle :- direct life cycle or simple life cycle that mean __________________
(Mature or immature?) cysts are passed with feces.
the parasite not need for intermediate host .
Mature
B.coli
Infective stage
Transmission :- by ingestion of ___________ (NOT in __________) with feces contain the ________.
Excystation occurs in the _________, and the __________ colonize in the large intestine.
Trophozoites undergo ________ to produce infective cysts.
contaminated food or water
undercooked meat
mature cyst ; small intestine
trophozoites; encystation
Pathogenesis of B.coli
Balantidium coli produces proteolytic enzymes that __________________ .
Colon ________ develops which allows for ______________
_________ and secondary bacterial infections develop .
___________ of the large intestine and appendix will occur.
break down and digest the intestinal epithelium
ulceration; infiltration by lymphocytes and leukocytes.
Hemorrhage; Perforation
Clinical manifestation of B.coli
A chronic course characterized by intermittent _____, Alternating periods of _________; abdominal pain, and weight loss.
Rarely, a more ___________ with _____ and _______ in stools may occur this may lead to ________ of the gut wall and intestinal _______ with subsequent peritonitis, mesenteric adenitis or extraintestinal disease to the lungs, liver and other organs
pulmonary hemorrhage,and symptomatic (hematuria) and asymptomatic urinary infection.
diarrhea; constipation
fulminant colitis ; blood and mucus
Ulceration; perforation
Treatment of B.coli
Tetracycline
Iodoquinol
Metronidazole
Control of of B.coli
Eradication of ___ contamination of food and water.
Cysts killed by ________
Resistant to ____ doses chlorine (halide tablets)
Avoid practices that allow ______ contact Improved sanitation in institutions.
fecal
boiling of water
low
fecal-oral
