Schistosomiasis -Hunter Flashcards
What is the risk of schistosomiasis (blood fluke)
1/6th of worlds pop
What are the major parasites that cause schistosomiasis?
Schistosoma mansoni; S. japonicum; S. haematobium
What are the minor parasites that cause schistosomias?
S. mekongi, S. intercalatum
S. manson and S. intercalatum is most commonly located in what country?
subsaharan Africa and western hemisphere of S. America
S. haematobium is limited to (blank) and is considered the (blank) schistosoma
Africa
urinary
S. Japoncium is found where?
china, philliapenes
Where do you find S. mekongi?
vietnam
Are the life cycles of the schistosomes similiar?
yes
Schistosoma is acquired through (blank)
wading through water
What is the life cycle of schistosomes?
cercariae enter skin-> migrate to lungs then liver-> then to mesentaric veins-> adults develop here -> males and females copulate and make eggs-> enter intestine-> passed in feces
Are schistoma mansoni eggs large?
yes
What is the female version of shistosomes and what does it need to survive
miracidia-> needs to be in a snail to survive
What am I talking about:
you need snails and a bad sewer system to have this pathogen survive
Schistosoma mansoni
The schistosoma egg cannot hatch until it hits (blank)
water
Adult schistomsome are (blank) to the immune system, the eggs are not
invisible
Since eggs of schistosomes have to erode its way through the blood vessel and into the bowel, eggs release (blank)
enzymes (this are crazy immunogenic)
In S. mansoni, what snail do you need for it to survive?
biomphalaria
In S. hematobium, what snail do you need for it to survive?
Bulinus
In S. Japonicum, what snail do you need for it to survive?
oncomelania
cercariae have a head that senses (blank)
amino acids
Use the names of schistosomes to describe life cycle:
cercariae- shistosomula- miracidia and cecariae
THe males shcistomsoma mansoni have 2 suckers that do what?
link them to the mesentaric veins.
How do the worms hide from the immune system?
worms have skin or tegument that allows them to acquire host moecules (such as RBC, glycotproeins and MHC molecules) (makes an antigenic disguise)
Cercarial penetration of skin can cause a transient (blank)
dermatitis
Migration of (Blank) through lungs can cause (blank) that can be severe in heavy infections
schistosomules
pneumonitis
What adult worms do you find in the superior mesentaric veins?
mansoni and japonicum
What adult worms do you find in the vesicle plexus of bladder?
hematobium (cause no clinical symptoms)
Onset of egg production causes (blank)
katayama fever (allergic response)
Intestinal or urinary bladder symptoms are due to eggs passing though tissue to lumen-> which can result in what?
severe hemorrhagic cystitis
gastroenteritis
Eggs swept up into portal circulation to liver cause (blank) and a (blank)
granulomas
T-cell mediated delayed hypersensitivity reaction to eggs
Blockage of sinusoids by eggs leads to (blank) and (blank)
pipestem fibrosis
portal hypertension
What are the cinical and lab findings of schistosomiasis?
Hepatosplenomegaly
Eosinophilia
hyperimmunoglobulinemia
With portal hypertension you wil get (blank), so some patients with schistosomiasis will have this.
ascites
In schistosoma mansoni, Eggs will cause fibrotic liver which will cause (blank)
pulmonary hypertension
What do the schistosoma mansoni eggs look like
like a chicken head with a beak
Schistosoma hematobium are distinguished in a H and E by…
have a spine at the ends of their egg
If you see blood/burning in the urine then you should think of what schistoma?
schistosoma hematobium
Schistosoma hematbium is acquired in (blan)
africa
What do the eggs of schistosoma japonicum?
small, no lateral spine and a tiny penis looking thing
How do you treat schistomas?
praziquantel
How can the immune system kill a schistocyte?
if the schistocyte has an IgG switch to IgE and immune system recognizes and attacks via granule release
Wht are the four malarial parasites?
Plasmodium vivax
Plasmodium ovale
Plasmodium malariae
Plasmodium falciparum
What is this:
sporocytes enter the skin and go straight to the liver and will rupture the hepatocyte and flood into the blood
Malaria
The leading cause of sepsis and septic shock is (blank)
malaria
What is the life cycle of plasmodium?
sporozites are injected into skin via mosquito-> merozites enter bloodstrem-> goes to liver-> ruptures heptocytes which releases merozoites->enters blood
(blank) form of plasmodium is what infects RBCS-> binds to target receptors of RBC and can get into it without rupture the RBC.
merozoite
Malaria is a (Blank) disease with many clinical manifestatins caused by proinflamatory and pyrogenic cytokines such as (blank)
systemic inflammatory disease
TNF-alpha
Where do you classical fever paroxysm?
malaria P-falciparum-daily P. Vivax- every other day P. Ovale- every other day P. Malaria-> every third day
What are important clinical and laboratory findings of malaria?
hepatosplenomegaly, anemia, hyperimmunoglobulinemia
What is the disease sequellae of malaria?
glomerulonephritis, nephrosis, cerebral malaria (most organ systems affected)
(blank) malarias relapse due to liver hypnozites that restablish infection
Vivax and Ovale
(blank) do not relapse but they can recrudesce (subclinical infection becomes active clinical disease)
Falciparum and malariae
Explain how malaria works
It is an intracellular amoebae which grows within the RBC by consuming the globin portion of hemoglobin leaving behind a black pigement-> eventually the RBC ruputre and the produced merocyte go out and infect other RBCs.
What is happening when you have rigors in malaria?
RBC are rupturing
What are the stages of malaria
Cold stage-> hot stage-> diaphoresis
What are the relapsing malarias?
P. vivax and P ovale
What are the recrudescing malaria?
p. falciparum and p malariae
A patient with plasmodium falciparium is the most common cause of (blank) and (Blank) in the world
sepsis and septic shock
Malaria loves the (blank) so kills fetuses :(
placenta
All malarias can cause immune complex disease which can cause (blank) …. worst in p malariae
glomerulonephritis
Treat falciparum malaria like (blank0
sepsis
IF you see a patient who is acutely febrile nad has traveled then think (blank)
malaria
In the ICU if you suspect malaria check blood (blank)
glucose
How should you treat a Falciparum malaria patient
Ensure correct fluid, electrolyte, and acid-base balance. Control fluid replacement to prevent circulatory overload and pulmonary edema. Anticipate renal and respiratory failure
(dont give steroids, heparin, epi)
What will you see in the kidney with malarai?
lumpy bumpy appearance cuz of immune complex caused by malaria
You see (blank) on the outside of malaria infected RBCs
Knobs (excretions produced by parasite)
How do you know you have plasmodium vivax?
stippling on surface, lots of spots more than 12, RBCs get bigger
How do you know you have plasmodium ovale
Its an ovale… lol
How do yo know you have plasmodium malaria?
less than 12 dots, stippling, RBCs dont get bigger
How do you know you have plasmodium falciparum>
can see it sitting on a platelet, you can see the rings, can have multiparasites in one RBCs. can have aplique forms, the gametocyte is crescent moon shaped.
(WHEN YOU SEE RINGS AND BANANAS!!!)
Susceptibility to vivax malaria is determined by the presence or absence of (Blank)
duffy blood group (parasite receptor)
(blank) allele is protective in west africa
HLA-B53
(blank) is a complex interaction of cell-mediate and humoral immune mechanism; immunity is species, strain and stage specific
Acquired immunity
Host RBCs dont have MHC on RBC so you dont get an (Blank) when parasites enter them
immune response
HOw can you get innate and acquired immunity?
Duffy blood group
Sickle cell
HLA b53
Antigenic variation and immunosuppresion
Is duffy positive or duffy negative helpful to plasmodium vivax
helpful, it allows vivax to enter the RBC
What are the drugs that kill the erythrocytic froms of malaria?
artemisinin (artemisinin combined therapy), chloroquine, doxycycline, halofantrine, quinidine, quinine, mefloquine, proguanil, pyrimethamine-sulfadoxine
What are the drugs that kill hepatic forms of erythrocytic forms of malaria and prevents relapses with vivax and ovale?
primaquine (contraindicated in G6PD deficiency)
Drug resistance in malaria is widespread; particularly (blank) resistance
chloroquine
(blank) is used for travelers
Chemoprophylaxis
How do you attempt to get rid of/ prevent malaria?
Mosquito control with long-lasting insecticidal nets and residual indoor insecticide sprayin
There is no malaria vaccine
What do you use chloroquine (4-aminoquinoline) for?
Prophylaxis and Therapy for Blood Stage Parasites (Resistance)
What do you use primaquine for (8-aminoquinoline)?
Used to Purge Liver Stage Parasites (Hypnozoites of P. vivax and P. ovale)
Why didnt eradication of malaria work
DDT was bad for people
mosquitos became resistant to DDT and insecticides, lack of funding, lack of community participation
Whats the worst malaria?
P. falciparum
What are the clinical complications of p. malariae?
immune complex
glomerulonephritis-leading to nephrotic syndrome
What are the clinical complications of p. vivax (p. ovale)?
splenic rupture
anemia (mild)
debilitating fevers
higher TNF alpha per parasite
What are the clinical complications of p. falciparum?
cerebral coma anemia pulmonary edema renal failure shock lactic acidosis hypoglycemia tropical splenomegaly pregnancy (maternal death, stillbirth, low birth weight, anemia)
HOw does malaria effect the mosquitos?
gametocytes in peripheral blood-> gametocytes are ingested with blood meal-> gamete formation occurs in stomach-> exflagellatio and fertilization occur in stomach-> oocyst formation occurs in wall of stomach-> sporozonite formation and release occur in stomach-> sporozites migrate to salivary gland-> sporozoite are injected into human host when infected mosquito takes second blood meal
