Blood flukes Flashcards
Three species of schistosomes that parasitize humans are regarded important. What are they?
- Schistosoma japonicum
- Schistosoma mansoni
- Schistosoma haematobium
Less common species of schistosomes are ____ found in Africa and ____ found in the Mekong Basin.
Schistosoma intercalatum; Schistosoma mekongi
Although these flukes reside in the blood vascular system, eggs are generally found in what sample?
stool
The eggs of what Schistosoma are occasionally seen in stool but usually seen in urine?
Schistosoma haematobium
Female worms are long and ____, with a body almost circular in cross sections.
thin and delicate
slender
The body of male worms is flattened behind the ventral sucker, as it is incurved ventrally to form a ____ in which the female reposes.
gynecophoral canal
Among the two Schistosome, which is longer?
male or female
female
but thinner cla
male is thicker due to gynecophoroal canal (for reproduction)
What structure of Schistosoma eggs assist in the retention of eggs in the blood vessels?
spines
+++ dinidilate ng worms vessels b4 oviposition so that eggs are laid and wedged firmly into the small vessels
The miracidium inside a Schistosoma egg produces an ____ that diffuses through the egg shell and helps to digest the overlying tissue.
enzyme
In blood flukes, the action of the ____ produced by the miracidium, together with necrosis via the spines, works to liberate the egg from the tissues into the lumen of the intestine or bladder.
enzyme
What stages are not present in the life cycle of Schistosoma
redia and metacercaria
The cause of pathology of Schistosoma is what?
eggs or adult worms
eggs
The cercaria of schistosomes have a ____ tail and anterior glands that assist in skin penetration.
forked
Upon skin penetration, the tail is lost and is now referred to as what?
cercaria minus tail = ?
Schistosomula
The cercaria minus the tail remains in the subcutis for about how many days?
about 2 days
After blood vessel invasion, flukes are carried to the lungs then to the ____ where they begin their growth.
Liver
liver sinusoids
After ____ weeks, the maturing worms commence a migration against the floow of blood in the portal system to their final location in mesenteric or vesicular veins.
two
final locations in the host will differ for each species
Habitat of Schistosoma mansoni
inferior mesenteric vein
in the region of the lower colon
____ is the smallest of the schistosomes that infect humans
Schistosoma mansoni
Diagnosis of schistosomiasis during the ____ period of the disease is based on the recover of eggs in the stool.
acute or chronic
acute
In the ____ stage of the schistosomiasis, eggs may not be found in the stool. Biopsy may be of value ‘coz eggs can be demonstrated in the tissues.
acute or chronic
chronic
common name of Schistosoma mansoni
Manson’s blood fluke
Intermediate host of Schistosoma mansoni
Biomphalaria spp.
Intermediate host of Schistosoma japonicum
Oncomelania hupensis quadrasi
common name of Schistosoma japonicum
Oriental blood fluke
Among the schistosomes, which is the most virulent as it lays the most number of eggs and is highly zoonotic?
Schistosoma japonicum
Habitat of Schistosoma japonicum
superior mesenteric vein
adjacent to the small intestine
Urinary schistosomiasis is generally caused by what Schistosoma?
Schistosoma haematobium
Common name of Schistosoma haematobium
Vesical blood fluke
or Bladder fluke (Zeibig)
Habitat of Schistosoma haematobium
Vesical, Prostatic, and Uterine venous plexuses
The Schistosoma haematobium eggs that are deposited in the walls of the bladder may break through and escape with the ____.
what sample?
urine
Diagnosis of Schistosoma haematobium is readily made by the recovery of eggs via ____ or ____ of the urine.
what is done sa wiwi?
centrifugation or sedimentation
Intermediate host of Schistosoma haematobium
Bulinus spp.
What do you call the schistosome that resembles S. japonicum in adult structure?
Schistosoma mekongi
Intermediate host of Schistosoma mekongi
Neotricula aperta spp.
Common name of Schistosoma mekongi
Mekongi blood fluke
The eggs of what parasite closely resemble Schistosoma haematobium but can be differentiated by a slight bend in the terminal spine?
Schistosoma intercalatum
Common name of Schistosoma intercalatum
- Cattle Schistosome
- Forest Schistosome
The eggshell of what Schistosome is Ziehl-Neelsen negative?
Ziehl-Neelsen = acid-fast din pala :oo
Schistosoma haematobium
All the other ones are positive (walang nakalagay s mekongi and malayensis tho)
Intermediate host of Schistosoma intercalatum
Bulinus spp.
After cercaria skin penetration of Schistosoma, what do you call the rxn that may be seen?
characterized as petechial hemorrhages + localized edema nd pruritus
Cercarial dermatitis
Swimmer’s itch (swamp itch)
Migration of the worms throughout the lungs may cause cough or ____.
hemoptysis
cough w/ blood
After the liver, when the flukes reach the mesenteric or vesical venules and lay eggs, what stage of schistosomiasis is seen?
acute or chronic
acute
When the developing schistosomes reach the liver, acute ____ may develop
inflammation of the liver
hepatitis
The acute stage infection by S. mansoni and S. japonicum may be characterized by what symptoms?
diarrhea or dysentery
The acute stage infection by S. haematobium may be characterized by what symptoms?
hematuria at the end of micturition (peeing)
sometimes dysuria (pain during micturition)
What do you call the systemic hypersensitivity rxn that is an early clinical manifestation of first infection or heavy infection with schistosomes? There is significant mortality at this stage of the disease.
hypersensitivity rxn = fever/syndrome
Katayama fever
Katayama fever is more common in what schistosome?
Schistosoma japonicum
S. mansoni pweds but katayama is under schistosomiasis japonicum (sa book)
What is the most common chronic infection in patients w/ S. mansoni or S. japonicum, also occurs regularly in S. haematobium infections?
schistosomiasis where?
Hepatic schistosomiasis
What disease is more common also in S. mansoni and S. japonicum infections and involves the intestinal tract and is suggestive of granulomatous colitis, w/ abdominal cramps and tenderness and intermittent bloody mucoid stools?
schistosomiasis where?
Intestinal schistosomiasis
____ schistosomiasis is seen with Schistosoma haematobium and is characterized by dysuria and hematuria.
Urinary schistosomiasis
What is usually the first sign of urinary schistosomiasis?
Terminal hematuria
What are conditions that are usually found in urinary schistosomiasis?
eosinop & bacteria in urine?
eosinophiluria & bacteriuria
What is usually seen with heavy Schistosoma haematobium infections where there is heavy egg concentrations that promote urothelial carcinogenesis?
Bladder cancer
usually a squamous cell carcinoma
Pulmonary involvement may be seen in all forms of schistosomiasis but is more common with ____ infections.
Schistosoma haematobium
egg deposition in the lungs leads to pulmonary fibrosis and cor pulmonale
Cerebral manifestations of schistosomiasis are most commonly seen in ____ infections.
Schistosoma japonicum
If S. japonicum is usually seen in cerebral schistosomiasis, which of the Schistosoma frequently affect the spinal cord?
- Schistosoma mansoni
- Schistosoma haematobium
Transverse myelitis, usually in the ____ area, is seen in spinal cord involvement and is associated with S. mansoni.
what region ng spine
lumbar area
Upon initial reaction, which of the cells release histamine that is cercaria-provoked through a marked dermal rxn?
mast cells
What are the two types of antibodies involved in the elimination of schistosomula in the body and is seen in immunocompetent hosts?
immunocompetent hosts = previously infected n so they have panlaban na
- IgG
- IgE
What develops around the eggs and is responsible for much of the pathology associated with schistosomiasis?
granulomas
Eggs of ____ may bypass the liver entirely. Venous blood from the vesical, prostatic, and uterine plexuses enters the hypogastric vein, from whence it goes by way of the common iliac vein to the vena cava, the right heart, and the lungs
Schistosoma haematobium
What is the common site of S. haematobium infection in women?
uterine cervix
granulomatous inflammation of the cervix is a common manifestation
What is the common site of S. haematobium infection in males?
urethra, prostate, seminal vesicles
even the spermatic cord & penises
Which of the schistosomes may invade the placenta and cause placentitis?
- Schistosoma haematobium
- Schistosoma mansoni
Drug of choice for schistosomiasis
Praziquantel
Oxamniquine
What is the preferred sx for the diagnosis of S. haematobium?
Urine
What do you call the test that serves as a confirmatory test for schistosomiasis?
Circumoval precipitin test
COPT
What are the reagents used in circumoval precipitin test?
Lyophilized eggs
from reservoir hosts (rabbits)
The formation of a ____ depicts a positive result for circumoval precipitin test.
bleb
bleb formation
wherein antibodies are present in px sample. u have an antibody specific to schistosomes and will react to form blebs
circumoval precipitin test process
no need to memo i think
- serum & reagent in slide
- incubation at 37o for 1-2 days
- bleb observation
What do you call the condition wherein adult schistosomes are always together to produce more eggs?
perpetual copulation
Spine description of the egg of Schistosoma mansoni
Prominent lateral spine
Spine description of the egg of Schistosoma japonicum
minute lateral spine
rudimentary spine (curved hook)
Spine description of the egg of Schistosoma haematobium
conspicuous terminal spine
malaki
same cla ni intercalatum (kaya u test via acid-fast: Ziehl-Neelsen)
How many eggs per cycle are produced by Schistosoma japonicum?
50-100
3k per day
How many eggs per cycle are produced by Schistosoma mansoni?
1-4
190-300 per day
How many eggs per cycle are produced by Schistosoma haematobium?
20-30
30 per day