babesia Flashcards
phylum
apicomplexa
Transmission: man infected by bite of a tick that belong to genus Ixodes
(intermediate host); can be transmitted through blood transfusion
Babesia
Dh of babesia
Animals (Deer)
Pathogenic: babesia spp
Babesia microfti
infective stage of babesia
trophozoites liberated via the bite of deer tick
Pear-shaped
babesia
Symptoms and Pathology: symptoms resemble Malaria
babesia
members of the Class Sporozoa in the Phylum
Apicomplexa. The subclass Coccidia includes species of Toxoplasma,
Coccidian parasit
Usually in pair or tetrads (resembling “maltese cross” appearance)
babesia
Diagnostic stage of cocci:
: oocysts demonstrated in feces
Diagnostic stage: demonstration of characteristic ring forms in Giemsastained blood smears (thick and thin smear
babesia
Life cycle of cocci parasite: in variety of nucleated cells
Schizogony (Asexua
2 classifications of cocci
✓ Intestinal Coccidian:
Tissue Coccidian
Life cycle of cocci parasite: in intestinal mucosa of definitive host infective
oocyst are excreted in the feces
Sporogony (Sexual)
Oral-anal route
. Cryptosporidium parvum
Important opportunistic infection in AIDS patients
Cryptosporidium parvum
o Red spherical bodies, four sphorozoites
o Oocysts are stained red against blue background
C,parvum: Modified acid fast stain in feces:
Infective stage of cocci;
oocysts
Acute self-limiting diarrhea
Cryptosporidiosis
Causes chronic diarrhea in immunocompromised person
Cryptosporidiosi
➢ Develop in brush border of intestinal epithelial cells
Cryptosporidium parvum
Sporulated oocysts, containing 4 sporozoites each (no
sporocysts), are passed in feces
C.parvum
c.parvum diseaase
Disease: Cryptosporidiosis
➢ Causes intestinal infection: associated with watery, frothy
diarrhea with oocysts shed in fece
Cryptosporidiosis
I.belli habitat
Small intestines of man
I. belli DH
Human
Modified AFS
➢ Oocysts stain from light pink to deep red (acid-fast
variable
C.caye
− infective oocysts ingested in contaminated food and water
− outbreaks have been associated with contaminated berries
Cyclospora cayetanensis
Mode of Transmission: ingestion of sporulated oocysts in fecally
contaminated food or water
I.belli
Elongately ovoidal in shape with one end narrower than
the other
I.belli; immature cyst
Contains 2 sporocyst, each containing 4 sporozoite
I.belli; mature csyt
i. belli disease
Disease: Human Coccidiosis
Symptoms range from mild gastrointestinal distress to severe
dysentery
i.belli
Often asymptomatic and self-limitin
human coccidiosis
In mild cases: mild abdominal pain and mucoid diarrhea
i.belli
In severe cases: severe abdominal cramps with milky,
watery diarrhea
i.belli
➢ Sporoblasts and/or sporocysts stain deep red
➢ Oocysts are ellipsoid with blunt ends
i.belli
Prevalent in AIDS patients/immunocompromised persons
T.gondii
Transmission:
➢ Accidental ingestion/inhalation of oocysts from cat feces
➢ Ingestion of undercooked meat or oocysts from cat feces
➢ Transplacental
➢ Organ transplant
T>gondii
Habitat: intracellular obligate parasite of endothelial cells,
mononuclear leukocytes, body fluids, and tissue of the host
t.gondi
Crescent appearance in tissue fluids
T.gondi
fast rapid, multiplication, acute phase
T,gondi tachyzoites
slow proliferation, chronic phase
t.gondi bradyzoite
Pseudocysts (group of bradyzoites) are also formed
t.gondi
➢ Female who first to acquire the infection during pregnancy may
transmit the infection to embryo resulting in fetal death, or
mental retardation on newborn, or blindness in later life
T.gondi
T, gondi disease
toxoplasmosis
Major cause of encephalitis in AIDS patients
toxoplasmosis
➢ Appears after the infection and regional lymph node
invasion
➢ Parasite is blood borne to many organs where
intracellular multiplication takes place
Acquired toxoplasmosis:
Major cause of congenital toxoplasmosis among the newborns:
➢ Congenital infection causes birth defects and mental
retardation
toxoplamsosis
➢ Methylene blue staining of tachyzoites inhibited by prior
addition of patient serum containing antibodies of
Toxoplasma
o Sabin-Feldman Dye tes
Newest group of obligate intracellular parasite
Microsporidia
▪ The most common microsporidia causing enteritis among patients with
AIDS
Enterocytozoon bieneusi (Encephalitozoon intestinalis)
▪ The organism is very small measuring about 1.5 – 4 u
Enterocytozoon bieneusi (Encephalitozoon intestinalis)
Method of infection:
➢ Not certain; most likely by ingestion of spore
Inhalation of spores, ocular exposure, and sexual intercourse may
also be route of transmission
Enterocytozoon bieneusi (Encephalitozoon intestinalis)
Characteristic feature: spores containing a polar tubule, used to inject
infective spore content into the host cells
Enterocytozoon bieneusi (Encephalitozoon intestinalis)
➢ Similar with Cryptosporidiosis
Enterocytozoon bieneusi (Encephalitozoon intestinalis)
o Usually in pair or tetrads (resembling “maltese cross” appearance)
B. Babesia species
Symptoms and Pathology: symptoms resemble Malaria
o Headache and fever
o Hemolytic anemia with hemoglobinuria in immunocompetent
host
babesia
Diagnostic stage: demonstration of characteristic ring forms in Giemsastained blood smears (thick and thin smear
babesis
Diagnosis:
➢ Sugar floatation technique
➢ Modified acid fast stain in feces:
o Red spherical bodies, four sphorozoites
o Oocysts are stained red against blue background
o Average size: 4 – 6 um
Cryptosporidium parvum
Diagnosis:
o Modified AFS
➢ Oocysts stain from light pink to deep red (acid-fast
variable)
➢ Average size: 8 – 10 um (larger than C. Parvum)
Cyclospora cayetanensis
o Demonstration of oocysts in feces (transparent containing 1-2
sporoblast)
o Modified AF
Isospora belli
abin-Feldman Dye test:
➢ Methylene blue staining of tachyzoites inhibited by prior
addition of patient serum containing antibodies of
Toxoplasma
Diagnosis:
o Electron Microscopy – necessary to speciate
o Serological testing
o Modified Trichrome stain:
Enterocytozoon bieneusi (Encephalitozoon intestinalis)
➢ Concentration must be 10x higher that traditional trichrome
stain
➢ Performed on unconcentrated specimen
➢ Spore walls stains bright pink; background stains green or
blue (depending on the couterstain)
Enterocytozoon bieneusi (Encephalitozoon intestinalis)
diagnostic stage of cryptospodium spp
oocyst with 4 naked sporozoites
infective stage of crpto
sporozoite
