Parisitology Flashcards
Other Diagnostic Methods
serology, tissue biopsy, blood smears, molecular testing
serology
not diagnostic, limited use in patients from endemic areas (for travel and return)
blood smears
malaria
molecular testing
try to choose cheaper option (better for research purposes)
T. cruzi
hemoflagellate, late disease presents with cardiomyopathy, arrythmia, death, megacolon, megasophagus
chagas’ disease
t. cruzi
sporozoans don’t
have organs of motility (t. cruzi is a FLAGELLATE)
definitie host
host in which reproduction (not necessarily sexual) occurs
vectors can also be
an intermediate host
intermediate hosts
there can be more than one
trypomastigote
human, infective, blood form, c for cruzi
amastigote
human, tissue form, binary fission, most commonly seen
epimastogote
bug, binary fission, intermediate host
t. cruzi definitive host
humans
triatomine bug
poops on you, kissing bug, t. cruzi, can get crushed up and ground in food
romana’s sign
t. cruzi, chagas’, gets face
why do we in america do not get t. cruzi
because we don’t live in mud houses, etc. (worse in Mexico) – problem in blood donations (seroprevalence >70%)
t. cruzi blood problem
can reactivate in heart transplants
acute phase t. cruzi; chronic
12-30 micrometers; +/- biopsy
toxoplasma gondii
neg for bacterial/viral infection, AIDS patient, headache, low WBC, “ring enhancing lesions”
t. gondii
sporozoan (does not move around), acute disease,
AIDS patient with headache
t. gondii
acute disease t. gondii
fevers, chills, headache, myalgia, lymphadenitis, fatigue
congenital t. gondii
1st trimester infection leads to spontaneous abortion, late infection leads to epilepsy, encephalitis, microcephaly, intra cranial calcifications, hydrocephalus, retardation
reactivation t. gondii
HIV patients, encephalopathy, meningoencephalopathy, cerebral mass lesions - multifocal
t. gondii association with schiz, parkinsons, alzheimers
uhh, maybe, i guess
cats
eats animal that ate fecal ooctyes, definitive host, t. gondii
cat prey
eat fecal oocytes from the cat, intermediate host, t. gondii
how we get t. gondii
eating animals with oocytes, consumption of unclean water, blood transfusion, maternal sources
cysts t. gondii
full of bradyzoites
oocysts, t.gondii
full of sporozites
tachyzoites
in humans, t. gondii, we are intermediate hosts and dead end hosts
reactivation of t. gondii
AIDS, ruptured brain cells, brady –> tachy
congenital t. gondii
problem when infection happens during pregnancy, trahyzoites cross placenta
main differential in AIDS and t. gondii
CNS lymphoma
serology in new borns t. gondii
iga and igm
oocytes in humans?
nope in cat
swollen legs
lymphatic filariasis
lymphatic filaris
elephantitis, wuchereria bancrofti, brugia malayi
w. bancrofti, b. malayi
mosquito introduces 3rd stage filarial larvae onto huma skin, develop into adults that live in lymphatics, adults produce microfilariae
in general, helminths
have to get out of the human to mature into adults ( like sea turtles they must leave their place of birth to grow!)
w. bancrofti, b. malayi microfilariae
sheathed, nocturnal periodicity
when mosquitos ingest microfilariae
they lose sheaths, migrate to insect thoracic muscles, and ultimately develop into 3rd stage larvae (proboscis)
b. malayi is restricted to
resitricted, Asia and Indonesia, intermediate host as mansonia and aedes mosquitos
resevoir for b. malayi?
macaques, leaf monkeys, cats
reservoir for w. bancrofti
none known
w. bancrofti area
responsible for most of infections, many more mosquito types, near the equator (like everywhere)
b. malayi is comparatively
smaller than w. bancrofti
looks like gallstone
is fasciola hepatica, sheep liver fluke
trematoes
have leafy shape
f. hepatica life cycle
sheep, water (WATERCRESS OH NO)
, plant, sheep
humans are not the dead end host in
f. hepatica
snail intermediate host
f. hepatica
f. hepatica chronic infection
become adult flukes in the bile duct and produce eggs that enter the feces, can be asymptomatic, can cause liver obstruction (cholecystitis, pancreatitis, cirrhosis)
ectoparasites
lice, bedbug, scabies, mite
endoparasites
single celled protozoa and multicellular helminths, many have free living non parasitic relatives
parasites
are eukaryotes that usually have complex life cycles
pathogenesis of parasites
depends on dose, mode of acquisition, passage and target organ, ability to evade host immune defenses, and host response to various stages of the paratsite
infectious dose
one large bolus is equivalent to several small additives over time
host response to the parasite
anaphylactic, toxic, cell mediated, or cytotoxic
most parasites are transferred via
fecal-oral routes
facultative parasite
can survive outside a host (acanthamoeba)
obligate parasite
most common, cannot survive without a host
reservoir host
harbor pathogen without showing ill effects
what type of host does every parasite not have
intermediate host
vector
arthropod that transmits infection, can also be intermediate host
public heath cares about
the vector AND the reservoir
watery diarrhea, camping
giardia (cyst stage)
stool culture usually checks for
shigella, salmonella, and campylobacteria
giardia
protozoa
protozoa can be found
extracellularly (blood - filariasis, intestine, urogenital system - schistosome) and intracellularly (tissue macrophages (leishmania), or RBCs (plasmodium))
differentiation of protozoa
size, nucleus (clumped, karyosome), cytoplasm appearance
size of protozoa
single celled eukaryotes, 2-100 micrometers
stool samples
at least 2
medications that interfere with stool samples
anti diarrheal,
how to collect stool
use wide mouthed container
seizures
neurocystericosis, cysts in the brain taenia solium
taenia solium (get it from)
eating undercooked pork (t. saginata from beef)
poglottoid
tape worm segment,
