Schistosoma

Question 1

what is the source of cercarie of schisto

Answer 1

transdermal from freshwater

Question 2

what is the most important human helminth infection

Answer 2

schistosomiasis

Question 3

how many people infected with schisto in africa

Answer 3

200 million

Question 4

how many people die due to schisto in sub saharan africa per yeat

Answer 4

200 000

Question 5

which parasite was found in 3100 bc mummies

Answer 5

schisto

Question 6

where does schisto mature un the definitive host

Answer 6

the blood vascular system

Question 7

schisto is associated with what

Answer 7

renal, bladder dysfunction, liver or intestinal disease

Question 8

wha are the intestinal schisto parasites

Answer 8

-mansoni
-japonicum
-mekongi
-guineesis, intercalatum

Question 9

where is mansoni found

Answer 9

middle east africa
caribbean
brazil
venezuela
suriname

Question 10

where is japonicum found

Answer 10

china
indonesia
philipines

Question 11

where is mekongi found

Answer 11

cambodia
lao

Question 12

where is guineensis and intercalatum found

Answer 12

rain forest of central africa

Question 13

which schisto is urogenital

Answer 13

haematobium

Question 14

where is haematobium found

Answer 14

middle east africa
corsica aka france

Question 15

which schisto is the most widely distributed and is endemic in its areas

Answer 15

mansoni

Question 16

construction of the egyptian dam in the 60s led to what

Answer 16

the virual elimination of haematobium from the nile delta but has brought the establishment of mansoni in upper egypt

Question 17

construction of diama dam in senegal river led to what

Answer 17

the introduction of schisto into mauritania and senegal

Question 18

construction of akosombo dam in ghana led to what

Answer 18

the introduction if shisto into lower volta river

Question 19

the movement of refugees and the displacement of populations resulted to what

Answer 19

the intro of schisto in somalia and djibouti

Question 20

what are the 3 major species of schisto

Answer 20

mansoni
haematobium
japonicum

Question 21

true or false: in schisto, females are bigger than males

Answer 21

so true

Question 22

what are the lil features of male schisto

Answer 22

-oral and ventral sucker
-gynocophoric channel for female to get in
-sturdy body and tuberculated tegument

Question 23

what is the ;enght of male schisto haematobium

Answer 23

10-15 mm

Question 24

what is the lenght of mansoni

Answer 24

6-12 mm fp male

Question 25

what is lenght of male japonicum

Answer 25

12-20 mm

Question 26

what is the intermediate host of schisto

Answer 26

snail

Question 27

what is the snail for haematobium

Answer 27

bulinus

Question 28

what is the snail for mansoni

Answer 28

biomphalaria

Question 29

what is the snail for japonicum

Answer 29

oncomelaniawhere

Question 30

are usually the cercariae in

Answer 30

fresh water

Question 31

how do schisto infect people

Answer 31

they penetrate the skin

Question 32

what is life cycle of schisto starting from penetration

Answer 32

-penetration of the skin -cercariae become schistosomula -larvae migrate first to the lungs through venous circulation -larvae migrate to the heart and into circulation -larvae mature in liver -worms mature and pair off -worms migrate to mesenteric vessels of bowel or bladder where females lay eggs -eggs excreted in feces or urine -eggs get into snail -miracidia develop into sporocyst and produce cercariae

Question 33

how long to schisto take to develop into mature miracidium

Answer 33

8-10 days

Question 34

what is the color of schisto eggs and what is their special characteristiv

Answer 34

they are yellowish brown and elongate with a spine

Question 35

what is the size of the egg haematobium

Answer 35

140u

Question 36

what is the size of the egg mansoni

Answer 36

140u

Question 37

what is the size of the egg japonicum

Answer 37

85u

Question 38

what is the life expentancy of shisto in tissues

Answer 38

21 days

Question 39

what is the lenght of the swimming ciliated miracidium and how long does it live for

Answer 39

100-200u and lives 8-12 hrs

Question 40

miracidium male or female gives rise to what and how long do they live for

Answer 40

-give rise to cercaria of the same sex -live up to 3-4 days

Question 41

penetration of schisto is triggered by what

Answer 41

chemical and theremal cues

Question 42

cercaria penetration is accompanied by what

Answer 42

-the transformation of the free living cercaria to a parasitic larval schistocomulum

Question 43

Schistosomules enter the capillary bed or the lymphatic system, migrating to where?

Answer 43

the right side of the heart and then entering the lungs

Question 44

juveniles of schisto feed on what and then what happens

Answer 44

erythrocyte and grow rapidely -after 10 days the schistosomules move through the pulmonary vein to the left side of the heart and then into systemic circulation

Question 45

3 weeks after penetration, the worms of schisto will reach what

Answer 45

hepatic portal vein

Question 46

initial egg production begins when for schisto?

Answer 46

-4-7 weeks after infection

Question 47

s mansoni mature females produce how many eggs per day

Answer 47

100-300 eggs

Question 48

how long do adult schisto adults live

Answer 48

3-8 yrs

Question 49

what is the first clinical sign of shchisto

Answer 49

skin bumps

Question 50

what is a clinical sign of s mansoni

Answer 50

cercarial dermatitis

Question 51

what causes swimmers itch

Answer 51

avian schisto

Question 52

true or false: cercarian dermatitis is an igg mediated hypersensitivity response

Answer 52

false it is an ige response

Question 53

what is cercarial dermatitis characterized by

Answer 53

-maculopapular, pruritic rash that manifests within several hours of exposure to the contaminated water and may persist for days

Question 54

when is acute dermatitis

Answer 54

4-10 weeks after infection

Question 55

what is the name of the acute stage of the acute stage os schisto and what is it

Answer 55

katayama fever -normally found in kids or adults with no previous exposure to the disease -it is a response to the sudden high levels of antigen exposure -is usually assocuated with the onset of egg deposition

Question 56

what are the clinical symptoms of acute schisto

Answer 56

-skin rashes -asthmalike episodes -daily fever -malaise -diarrhea -swollen lymph nodes -aching joints

Question 57

which is most common with katayama fever in terms of which schisto

Answer 57

japonicum

Question 58

in schisto: accumulation of eggs and fibrotic reactions leads to what

Answer 58

cirrhosis and portal hypertension -ascites (fluid accumulation in the abdominal cavity) is common -some eggs pass the liver, lodging in the lungs, brain and other organs

Question 59

in s haematonium, fibrosis of the bladder may lead to what?

Answer 59

ureteric obstruction and renal failure

Question 60

true or false: s mansoni can cause growth stunting

Answer 60

true due to chronic infection

Question 61

pathology of schisto is due to what

Answer 61

egg deposition in tissues and not adult worm

Question 62

-eggs become surrounded by granulomas and antigen leakage lead to what

Answer 62

delayed type hypersensitivity aka DTH reactions

Question 63

what is the granuloma

Answer 63

concentric layers of cells that together form the distinctive lesion

Question 64

what is the central focus of the granulomas of schisto

Answer 64

-formed by 2 cell types: -epitheloid cells aka macrophages -multinucleated giant cells (cytoplasmic fusion of macrophages fue to stimulation with macrophages)

Question 65

what is the next layer after the central focus of granulomas

Answer 65

lymphocytes

Question 66

what is the outerlayer of schisto granuloma

Answer 66

fibroblasts

Question 67

what is the immune response of schisto

Answer 67

-th1 -aimed at adult worm in early stages which shifts to eggs induced th2 biased profile 6 weeks post infection

Question 68

in schisto; egg antigens directly suppress what type of response

Answer 68

th1 response

Question 69

Major components of the granulomatous response to schistosome eggs in the host liver and the main cytokines and chemokines that regulate this response. what are the cytokines and chemokines

Answer 69

-il 17, 23, 4, 19, 13 and 5

Question 70

what is the difference between the 2 pathologies of schisto

Answer 70

-severe: th17, th1 and th2 -mild: th2 and treg

Question 71

Schistosoma infection triggers a Th2 type response: which types of antigens and cells are involved

Answer 71

-ige -mast cells -eosinophila aka il4-5

Question 72

how is adcc induced in shisto

Answer 72

-by the interaction between the ige and igg with fd receptors on eosinophils

Question 73

ige dependant killing in shisto is mediated by what

Answer 73

eosinophils

Question 74

what are the other ways for ig isotypes to also kill

Answer 74

-toi, rni etc

Question 75

do people with schisto develop age dependent development of immunity

Answer 75

yup the egg counts go lower with age

Question 76

what is the correlation with igg titers and reinfection

Answer 76

-negative -aka low igg=high egg count -high igg=low egg amount

Question 77

what is the correlation between igm titers and reinfection

Answer 77

-high igm=high egg count aka it is positive

Question 78

ig in shisto is associated with what

Answer 78

protection

Question 79

Diagnosis: intestinal schistosomiasis

Answer 79

1. History of freshwater exposure 2. Stool for O&P (egg counts and viability) 3. Serology-- Elisa and Western Blot 4. Antigen capture 5. Eosinophilia 6. Rectal snips or biopsies 7. Liver biopsy 8. Ultrasound or CT of abdomen

Question 80

tests based on the detection of schisto antigens what happens?

Answer 80

-become positive as soon as antigens are present and become negative quickly after cure

Question 81

monoclonal antibodies to schisto antigens have led to what

Answer 81

to the development of sensitive dot immuno assays aka very small sample quantities

Question 82

treatment to schisto

Answer 82

Drug: Praziquantel - WHO recommended dose 40 mg/kg body weight In case of treatment failure; S. mansoni - Oxamniquine S. haematobium – Metrifonate

Question 83

are there any vaccines for schisto

Answer 83

nope