BLOOD FLUKES Flashcards
where do blood fluke species inhabit?
portal bloodstream of vertebrates
oriental blood fluke
s. japonicum
visceral blood fluke
s. haematobium
manson’s blood fluke
s. mansoni
s. japonicum & s. mansoni adult worms migrate to
mesenteric venules of bowel/rectum
s. hametobium adult worms migrate to
venous plexus of bladder
organ of maturation of schistosomes in humans
liver
freq. found on superior mesenteric veins
s. japonicum
occurs often in the inferior mesenteric veins
s. mansoni
schostosomes: drains small intestine
s. japonicum
s. haematobium most often inhabits in the ?
vesicular and pelvic venous plexus of the bladder
found in rectal venules
s. haematobium
only schistosoma in small intestine
schistosoma japonicum
it is what s. japonicum males forms wherein females will go inside for copulation; where female worm resides
gynecophoral canal
describe s. japonicum ova shape and spine
shape: ovoidal, rounded or pearshaped
spine: CURVED hook/spine or LATERAL KNOB
most commonly presented and most important characteristic of s. japonicum
lateral KNOB
miracidium hatches from the egg in what kind of water environment & temperature
slightly alkaline clean water; 25C to 31C
miracidium stimulus
light (phototactic)
infective stage of snail
miracidia
emerges from daughter sporocysts
cercariae
infective stage to humans
cercaria
mode of transmission
skin penetration
adapted to survive in SERUM or physiologic SALINE at 37C
schistosomulae
develops from cercariae after skin penetration
schistosomulae
what is found at the exterior portion of the male s. mansoni
tuberculate exterior
describe the ova shape and spine of the s. mansoni
shape: elongated oblong
ova spine: LATERAL SPINE
describe the ova shape and spine of the s. haematobium
shape: elongated oblong
ova spine: TERMINAL spine
s. japonicum intermediate host
oncomelania hupensis quadrasi
s. mansoni intermediate host
biomphalaria
australorbis
s. haematobium intermediate host
bulinus
local cutaneous hypersensitivity; pruritic papular rash that develops 24 hrs after exposure
cercarial dermatitis/swimmer’s itch
systemic hypersensitivity; may have lymphadenopathy, hepatic, and splenic enlargement due to the migration of worms through the circulation
katayama fever
gastrointestinal involvement = enlargement of liver, spleen, anemia, ascites, has CNS involvement
chronic stage
sensitive for MODERATE and HEAVY infections; not adequate for light infections (<10 g stool)
Merthiolate-Iodine Formalin Concentration Technique
for ENUMERATION OF EGGS; used for evaluating epidemiology, effect of control measures, drug trials
kato katz technique
indirect hemagglutination using adult worm and egg antigens
Cercarian Hullen Reaction (CHR)
Cercarian Hullen Reaction (CHR) positive reaction is indicated by
formation of PRECERCARIAL SHEATH around cercariae
CHR positive in CSF =
wrinkled surface
CHR positive in serum =
bubbles
based on patient serum precipitation with lyophilized eggs or purified live eggs identifed under microscope
Circumoval Precipitin Test (CPT)
Circumoval Precipitin Test (CPT) is useful for the diagnosis of ?
s. mansoni
s. japonicum
blood flukes treatment
praziquantel
found in Africa and pockets of the Middle East
s. haematobium
found in China, Philippines, Sulawesi
s. japonicum
found across sub-Saharan Africa, Brazil, Venezuela, Suriname (South America), Carribean, Arabian Peninsula (sporadic)
s. mansoni
3 less common human-infecing schistosomes
s. mekongi
s. intercalatum
s. guineensis
blood flukes epidemiology in the Philippines
Sorsogon
Oriental Mindoro
Samar
Leyte
Bohol
Mindanao (except: Misamis Oriental)
blood flukes: prevention
avoid s
