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179 Cards in this Set
- Front
- Back
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give the breakdown on campylobacter jejuni?
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motile gram neg curved rods (coma or seagullshaped organisms).
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what does growth of campylobacter strains require/
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selective media, microaerophilic conditions and incubation at 42 degrees C
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campy jejuni is the most common bacterial cause of this?
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darrhea
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what type of food are most campy infections associated with/
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improper handling and preparation fo poultry
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is the infectious dose of campy high or low?
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low - only 500 organisms - those present in one drop of chicken juice
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describe what campy does in the intestines?
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colonizes the intestinal mucosal layer mediated by flagella and putative adhesins- the organisms invade and or translocate across the epithelial surface to the underlying tissue where undefined virulence factors are released
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what happens to the intestines with campy infection?
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acute nonspecific neutrophicl and monocytic inflammatory reaction causing tissue damage in the lamina propria and jejunal epithelium as seen in crohns and UC
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some strains of campy produce this toxin?
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heat labile cholera like enterotoxin-->watery diarrhea
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what severe symmetrical ascending muscle weakness and facial diplegia disorder may be associated with C. jejuni?
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Guillain Barre syndrome
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poultry exposure as a cause of enteritis is often associated with these organisms?
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campy, salmonella, ecoli 0157:H7 and shigella
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describe salmonella?
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gram negative rods, non-capsulate, do NOT ferment lactose, produce acid on fermentation of glucose, reduce nitrates and no not carry cytochrom oxidase
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nontyphoidal salmonellae are second only to this organism as a cause of food borne illness in the US
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campy jejuni
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what are the main reservoir for salmonella?
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poultry, eggs, dairy products and pet reptiles
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how is salmonella infection transmitted/
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acquired by ingestion fo contaminated food or water, by contact with infected animals, or by person to person transmission
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within __to __hours of ingestion fo salmonella in food gastric acid sensitive nontyphoidal salmonella penetrate teh GI mucosa.
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6 to 48 hours
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how do salmonella bugs adhere to the distal portions of teh small intestine?
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often mediated by fimbriated adhensins
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what do salmonella do to the normal brush border of teh small intestine?
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alter it within in minutes of infection
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a localized invasion in the intestinal epithelial cells by salmonella mediated by bacterial invasins follows resulting in overwhelming influx of this to the intestines
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neutrophils
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the damage to teh intestine by salmonella results in self limited but often ___diarrhea
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bloody
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in complicated enteritis phagocytosis by macrophages results in the ____throughout the reticuloendothelial system and invasion into the blood stream.
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dissemination
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invasion into the blood stream, as with complicated salmonella infection, can lead to this condition?
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bacteremia
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what things mediate the systemic inflammatory resposne syndrome (sepsis) seen in salmonella infection that becomes complicated/
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LPS and cytokines
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are antibiotics used to treat nontyphoidal salmonella?
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no, in otherwise healthy peopel use of antibiotics may lead to protracted diarrhea nd other symptoms of enteritis-- in immunocompromised, neonates and peopel older than 50 antibiotic treatment with gluoroquinolone should be considered
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salmonella typhi causes this disease?
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typhoid fever
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all salmonella are gram __rods
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negative
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is S typhi encapsulated?
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yes
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what antigen for virulence does S typhi carry?
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K also known as Vi for virulence
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does S typhi infect only humans?
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yes
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carriers fo S typhi often have this comobidity?
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biliary tract abnormalities including gallstones
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how is S typhi transmitted/
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fecal oral route (person to person), or by ingestion of food and water contaiminated either by a carrier or an actively infected individual
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risk for contracting S typhi is increased in ____travelers
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international
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what is teh incubation period for S typhi?
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3 days to 3 months, depending on the infecting dose
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typhoidal salmonellae bind to these cells in teh intesting by an uknown adhesin
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M cells
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following invasion of the M cells with salmonella typhi the M cells die and deliver the invading salmonella to this region/
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Peyer patch
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a distinctive feature critical to typhoid (enteric fever) is the ability of salmonella typhi to survive and multiply within this thing?
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within macrophages
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an infiltration of mononuclear cels into the ___mucosa is a characteristic finding of typhoid fever
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colonic
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the organisms of salmonella typhi carrying Vi antigen resist this type of killing by the immune system?
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phagocytic killing
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how do salmonella typhi strains carrying Vi antigen resist killing by phagocytes?
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they inhibit the oxidative burst and multiply within the mononuclear cells
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facultative intracellular organisms (S typhi) are carried by teh monocytes and delivered to teh reticuloendothelial system causing enlargemtn of these two organs/
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liver and spleen
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when secondary bacteremia has occurred in an S typhi infection, and a critical number of organisms have replicated in teh blood stream these signs and symptoms will appear?
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enteric fever, including abdominal pain, heart rate may be lower than expected based on patient's fever, erythmatous maculopapular rash (rose spots) caused by thrombocytopenia and vascualr capillary leakage, and the gallbladder is infected
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how does salmonella typhi cause abdominal pain?
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it results form the secretion of cytokines and pyrogens by macrophages
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what elicits teh systemic inflammatory resposne seen in salmonella typhi infection?
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LPS of the gram neg outer membrane (causes septicemia)
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typhoidal salmonella are particularly resistant to this, and they reenter the intestine from the gallbladder and cause diarrhea/
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bile
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what is the treatment for S typhi?
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chloramphenicol, ampicilin, or TMP/SMX----> for multidrug resistnat strians though need to use fluoroquinolones particularly ciprofloxacin
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what is tenesmus as caused by Shigella flexneri?
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a feeling of incomplete defecation
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describe Shigella?
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gram neg rod, nonmotile, noncapsulate, facultative ANaerobes, do NOT ferment lactose,
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what is dysentery?
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a rapid descending course fo infection with fever and abdominal pain progressing to mucoid diarrhea with bloody stools (colitis)
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in the US shigellosis is most often caused by this species?
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Shigella sonnei
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in the developing world Shigellosis is most often caused by this species of shigella?
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Shigella flexneri
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which of teh four shigella species is the most virulent?
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shigella dysenteriae
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how is shigella transmitted?
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direct or indirect fecal oral tranmission from patient or carrier
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in the US S sonnei causes disease primarily in this age group?
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elderly and yougn children
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S sonnei in US is a common cause of outbreaks of diarrhea in this location?
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day cares
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does shigella have a low or high infective dose?
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low as few as 10 organisms needed to cause illness
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what is teh incubation period for shigella?
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1 to 3 days
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in the colonic mucosa the invasive shigella species penetrate M cells and are taken up by ____in the lamina propria
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macrophages
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infected intestinal cells (with shigella) produce attractant for ___which migrate between epithelial cells resulting in a breakdown of tight junctions and facilitates local spread of shigella
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neutrophils
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passage of shigella into adjacent epithelial cells occurs through these?
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finger like projections
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this host protein is essential in the cell to cell spread of infection with shigella
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L -CAM
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when sufficient number of shigella bacteria have invaded cells, the cells die owing to intracellular multiplication fo bacteria and the colonic mucosa sloughs off forming this?
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ulcer
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in severe forms of shigellosis, which is highly endemic in south asia, THIS toxin contributes to the severity fo teh disease caused by S dysenteriae type 1.
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shiga toxin (Stx)
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what is the MOA of shiga toxin?
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inhibits protein synthesis targeting the 23 S ribosomal RNA. kills intestinal epithelial cells and endothelial cells resulting in blood loss.
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what are teh systemic complications associated with toxin producing shigellae infections/
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hemolytic uremic syndrome (disease characterized by microangiopathic hemolytic anemia, acute renal failure and a low platelet count (thrombocytopenia). ), and shiga toxins also cause thrombotic thrombocytopenic purpura
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what is teh treatment for shigellosis/
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TMP/SMX- and then for resistant strains quinolones are useful- administrationfo antibiotics for 3 to 5 days is sufficient
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are antidiarrheal agents recommended for a person with invasive bacterial infection that results in diarrhea?
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no
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what is the most common pahtogen isolated from bloody diarrhea?
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E coli 01257:H7
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how do you identify E coli 0157:H7?
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indole positive, lactose positive, sorbitol nonfermenting isolate (on sorbitol-MacConkey agar) that is positive for agglutination of 0157-specific antibodies. --E coli is a gram neg rod
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can some strains of E coli produce shiga toxins?
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yes
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what are teh major vehicles for E coli 0157:H7 infections?
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ground beef and unpasteurized milk and unpasteurized apple cider (made from apples picked up from the ground contaiminated by bovine feces)-- then spread fecal oral
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what age group is likely to develop severe complication from E coli 0157:H7 infection?
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children under 5 and the elderly
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how does E coli 0157:H7 affect teh enterocytes of teh gut?
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dramatic loss of microvilli and rearrangement of cytoskeleton elements with a proliferation fo actin beneat areas of intimate bacterial attachment
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how long does acute bloody diarrhea and abdominal cramps with little or no fever last with E coli 0157:H7 infection?
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1 week
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what are the most serious complications of E coli 0157:H7 infection?:
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hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenia purpura (TTP)
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most cases of E coli 0157:H7 infection do or do not require antimicrobial therapy?
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do not
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what is teh most common cause of watery diarrhea in travelers?
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ETEC
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what organism causes rice water diarrhea?
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Vibrio cholerae
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describe Vibrio cholerae?
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curved (comma shaped), Gram neg rod highly motile, oxidase positive facultative ANaerobes
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organisms of Vibrio cholerae that agglutinate in a 0:1 anti serum cause this?
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epidemics and pandemic of cholera
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what is teh major mode of transmission of Vibrio cholerae?
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contaminated food and water
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people with this condition are at increased risk for contracting Vibrio cholerae
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achlorhydria
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non-0:1 cholera vibrios inhabit costal waters in the US especially the gulf coast and cause diarrhea associated with consumption fo this?
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raw shellfish
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this Vibrio species can cause wound infection and sepsis particularly in patients with cirrhosis?
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Vibrio vulnificus
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cholera toxin is a potent ___toxin produced by V cholerae that causes severe watery diarrhea
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enterotoxin (An enterotoxin is a protein toxin released by a micro-organism in the lower intestine)-(These toxins have A and B subunits. The A subunit is responsible for the loss of permeability of the intestinal endothelial cells. The B subunit acts as a syringe, injecting the A subunit into the cytoplasm. )
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how does cholera toxin work?
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functional A subunit activates adenylyl cyclase cascade system by irreverisble transfer of an ADP ribose subunit from NAD to membrane Gs protein, thereby raising intracellualr concentrations of cAMP int eh intestinal epithelial cells. cAMP inhibits teh absoptive sodium transport systen int eh villus cells and activates teh excretory chloride transport system in crypt cells causing accumulation fo sodium chlorid int eh lumen-->watery diarrhea results as passive movement of water follows the chloride osmotically
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what is teh main treatment for cholera?
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oral and IV rehydration therapy is primary followed secondarily by treatment with doxycycline (drug of choice) or fluoroquinolone (ciprofloxacin) can be used
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prior antibiotic use is commonly associated with development of diarrhea caused by this organism?
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Clostridium difficile
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describe C diff?
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strictly ANaerobic, gram pos, spore forming robs, produce A and B toxins
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how can you detect the A and B toxins of C diff?
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ELISA (sensitive, specific, and simple)
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primary (index) cases of C diff infection occur by endogenous mode in precolonized patients exposed to antibiotics. secondary cases occur via exogenous transmission of ___
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spores
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what are the most commonly incriminated antibiotics that can kill off the gut fauna and induce a C diff infection/
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clindamycin, cephalosporins and ampicillin
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C dif associated diarrea CDAD is ___mediated
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toxin
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how doe A and B toxins produced by C dif work, MOA?
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bind to cellualr GTP binding proteins int eh (Rho family within target cells). the toxins inactivate these proteins by glycosylation, dysregulating the actions of the cytoskeleton of epithelial cells of teh colonic mucosa, causing depolymerization of actin. break-up of actin filaments causes profound cytopathic effect, damaging the cellular lining of the bwel wall causing erythmatous and friable colonic mucosa, ulceration and hemorrhagic necrosis
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what is teh treatment for C dif associated diarrhea?
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discontinuation of the offending agent and implementation of any necessary supportive measures. preferred oral antimicrobial agent is metronidazole
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what is a complication of C diff associated diarrhea?
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pseudomembranous colitis, occurs in untreated cases and is characterized by multiple elevated, yellowish white plaques within the colon. toxic megacolon is a serious sequelae of pseudomembranous colitis and may lead to sepsis due to perforation and polymicrobial infection
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what does polymicrobiral infection refer to?
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infection with multiple species of organisms
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diarrhea in infants is often due to this?
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viruses
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describe rotavirus?
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nonenveloped RNA virus, shaped like wheels, segmented genome, with 11 segments fo double stranded RNA genome,
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has gene reassortment played any role in genetic diversity fo rotaviruses?
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no
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rotaviruses and other enteric viral agents grow poorly in cell culture so this is needed for diagnosis?
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assays that detect viral antigen in stool specimens have become the most widely used method of diagnosis- enzyme immunoassay
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enteric viruses are responsible for the majority of cases of ___worldwide
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gastroenteritis
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rotaviruses are the single most important cause of severe dehydrating diarrhea in this age group?
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infants and children younger than 3
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rotavirus infection has a ___distribution in teh US with transmission occruing during the ___months
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seasonal, winter months
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how is rotavirus transmitted/
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fecal oral route, both through close person contact and through fomites
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what is a fomite?
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A fomite is any inanimate object or substance capable of carrying infectious organisms (such as germs or parasites) and hence transferring them from one individual to another.
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rotaviral infection of teh villus tip cells of teh small intestine results in destruction of these cells?
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mature absorptive cells
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damage cells on villi in a rotavirus infection are replaced by these cells, which cannot absorb carbs or other nutrients efficiently resuliting in osmotic diarrhea
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immature crypt cells
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is there any treatment for rotaviral infeciton?
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no specific antiviral agent for this disease, only symptomatic care
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describe norovirus?
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spherical nonenveloped virus positive sense single stranded polyadenylated RNA
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how can differentiation of NV from other similar viral pathogens be made on clinical and epidemiologic grounds?
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1. incunbation period is 24 to 48 hours, 2.vomiting occurs in 50% or more of cases, 3. duration of illness ranges from 12 to 60 hours, and 4. diarrheal illness rapidly spread among many individuals
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what is required to concentrate and visualize NVs?
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human antibodies
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the clustered illnesses of NV occur in these settings?
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families, communities, cruise ships, nursing homes, and other institutional settings
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how are noroviruses NV transmitted?
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fecal oral route primarily
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is norovirus contagious?
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highly contagious
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how many viral particles of NV are needed to infect an individual?
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as few as 10 viral particles
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what is teh incubation period for NV?
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24 to 48 hours, but cases can occur within 12 hours of exposure
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what does he proximal small intestine look like in a person with a NV infection?
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shortened atrophied villi, crypt hyperplasia, and infiltration of the lamina propria by polymorphonuclear and mononuclear cells
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what are two of the most common colonic ulcerative diseases?
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E. histolytica and S. dysenteriae
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what are teh two forms that E. histolytica can be in?
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cyst and trophozoite
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which one, cyst or trophozoite, is fragile and will die outside of the host/
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trophozoite
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which form the cyst of trophozoite is the infective form?
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cyst
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how does the cyst of E histolytica appear?
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spherical with 4 nuclei with central karyosomes
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what is teh only intestinal parasite other than E histolytica that is suspected of causing diarrhea/
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D fragilis
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what is the natural reservoir of of E histolytica
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humans
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how is E histolytica transmitted?
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ingestion of mature cysts in fecally contaminated food water or hands
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what are the virulence factors linked to invasion of colonic mucosa?
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cytooxins, cysteine proteinase,
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what do lesions in the colon look like with a E histolytica infection?
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non specific colitis with inflammatory cells to flask shaped ulcers and may extend through tissue planes
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what is the treatment for E histolytica?
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metronidazole
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in some patients with persistent colonization the trophozoites of E histolytica invade the blood stream and reach these organs
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liver, brain and lungs
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how do patients with amebic liver disease present?
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1 to 2 week history of fever, chills, leukocytosis, RUQ pain, and enlarged liver
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prolonged diarrhea, foul smelling stools and flatulence are particularly associated with this agent?
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protozoal agent
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describe G. lamblia?
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intestinal flagellate, the trophozoite is pear shaped and has a convex dorsal surface, a flat ventral surface with a sucking disk and four pairs of flagella. the mature cyst is an oval structure that has four nuclei and is encased ina thin wall composed of N acetylglucosamine
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what is teh mode of transmission of Giardia lamblia?
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fecally contaminated water and hand to mouth transfer
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excystation occurs in the small intestine promoted by this?
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gastric acid
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what is teh mechanism of attachment of teh trophozoite giardia?
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1. ventral disc with contractile proteins, 2. flagella mediated hydrodynamic forces, 3. receptor ligand interaction mediated by lectin proteins
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how do trophozoites replicate/
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longitudinal binary fission
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this immunoglobulin can prevent adherence of giardia organisms to the gut?
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IgA- but giardia has an IgA protease that inactivates the hosts IgA
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are trophozoites invasive and toxigenic?
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no they cause watery diarrhea by disrupting the brush border by microvilli injury causing villus atrophy (via proteinase or mannose binding lectin)
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what is teh drug of choice with giardia infections/
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metronidazole- given for 7 days (albendazole and paromomycin (in pregnancy) are alternatives though they are less effective)
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a 35 year old man with AIDS presents with several weeks of watery diarrhea, he has lost 20 lbs and is has been off his highly active antiretroviral therapy (HAART) for several months due to intolerance. what is causing this man's infection?
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Cryptosporidium parvum
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a 35 year old man with AIDS presents with several weeks of watery diarrhea, he has lost 20 lbs and is has been off his highly active antiretroviral therapy (HAART) for several months due to intolerance. describe the oocysts of this species that is infecting him?
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acid fast
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a 35 year old man with AIDS presents with several weeks of watery diarrhea, he has lost 20 lbs and is has been off his highly active antiretroviral therapy (HAART) for several months due to intolerance. what is the mode of transmission of this organism?
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zoonotic fecal oral from infected animals.
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who is at risk for a cryptosporidium infection?
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people with AIDS and bone marrow transplants
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what is the site most commonly infected with C. parvum?
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jejunum
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C parvum is considered an intracellular but extracytoplasmic infection what does this refer to?
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the protozoa carry out their entire life cycle among the microvilli of the small intestine. the organisms focally disrupt the microvilli and slide in between host cells enveloping themselves in teh host cell membranes
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in immunocompetent people how long does C parvum diarrhea last?
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2 weeks or less
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in immunocompetent people how many lifecycles does C parvum go through?
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one or two
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in AIDS patients how is teh diarrhea of C parvum characterized?
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protracted and severe watery diarrhea
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is there a reliable treatment for C parvum?
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no reliable one though several antibiotics may have partial efficacy, including paromomycin, nitazoxanide, azithromycin.
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a 3 year old girl was brought to ED following a 3 week history of nausea, poor appetite and abdominal pain, she had not had any bowel movements int eh last 2 days. the patient is of mexican origin and had recently moved from mexico to south texas. describe this organism?
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Ascaris lumbricoides is largest intestinal nematode (roundworm) in humans (20 to 35 cm in length), the unfertilized eggs have a characteristic bumpy appearance, the eggs are not infectious until the larva develops inside or eggs mature.
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how could a child acquire Ascaris lumbricoides?
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thour ingestiion of infective (larval) eggs from soil contaminated by human feces
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a 3 year old girl was brought to ED following a 3 week history of nausea, poor appetite and abdominal pain, she had not had any bowel movements int eh last 2 days. the patient is of mexican origin and had recently moved from mexico to south texas how would you diagnose this condition?
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microscopic identificaiton of eggs in teh stool
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a 3 year old girl was brought to ED following a 3 week history of nausea, poor appetite and abdominal pain, she had not had any bowel movements int eh last 2 days. the patient is of mexican origin and had recently moved from mexico to south texas. in what age group is this disease most prominent?
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ages 3 to 8
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once the eggs of Ascaris lumbricoides are swallowed what happens?
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the larvae hatch invade the intestinal mucosa and are carried via portal then systemic circulations to the lungs. the larvae further mature in teh lungs (10 to 14 days) then penetrate alveolar walls. during teh lung phase of larval migration pulmonary symptoms can occur with cough, dyspnea, hemoptysis and eosinophilic pneumonitis. the larvae then ascend the bronchial tree and are swallowed. they reach the small intestine and devleop into adult worms. adult worms live in tehlumen and the female may produce eggs which are passed in the feces
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helminth infection induce this immune response?
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TH2 resposnes characterized by eosinophilia. an TH2 cells also induce antiparasitic antibodies (of teh IgE isotype) that express multiple effector functions in the immunity to helminths
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a 3 year old girl was brought to ED following a 3 week history of nausea, poor appetite and abdominal pain, she had not had any bowel movements int eh last 2 days. the patient is of mexican origin and had recently moved from mexico to south texas what should be the treatment?
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mebendazole and albendazole are the drugs of choice.
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a 42 year old man presents with 3 weeks of worsening diarrhea, abdominal pain and fevers. he has noticed an itchy rash on his buttocks and groin area for the past 2 weeks and he has had a 15 lb weight loss. his symptoms began when he returned from El Salvador. what is the infective stage of the organism causing this man's disease?
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filariform larvae are the infective stage
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a 42 year old man presents with 3 weeks of worsening diarrhea, abdominal pain and fevers. he has noticed an itchy rash on his buttocks and groin area for the past 2 weeks and he has had a 15 lb weight loss. his symptoms began when he returned from El Salvador. what would microscopic Ova and parasite examination fo freshly passed feces froma symptomatic patient like this man reveal?
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rhabditiform larvae
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a 42 year old man presents with 3 weeks of worsening diarrhea, abdominal pain and fevers. he has noticed an itchy rash on his buttocks and groin area for the past 2 weeks and he has had a 15 lb weight loss. his symptoms began when he returned from El Salvador. how can one acquire this infection?
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by contact with contaminated soil...the filariform larvae are able to penetrate intact skin
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a 42 year old man presents with 3 weeks of worsening diarrhea, abdominal pain and fevers. he has noticed an itchy rash on his buttocks and groin area for the past 2 weeks and he has had a 15 lb weight loss. his symptoms began when he returned from El Salvador. what organism is causing this man's symptoms?
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Strongyloides stercoralis
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where do strongyloides stercoralis adult females reside in the human host?
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upper small intestine (eg jejunum) whre the small worms burrow into the mucosa causing GI symptoms. heavy infections may lead to bloody diarrhea
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what is present int he patient's blood in an acute and chronic state of strongyloides stercoralis infection?
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blood eosinophilia and serum IgE is elevated.
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larval migration of Strongyloides stercoralis under the skin in the buttocks and groin area causes what symptoms?
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urticarial, raised, erythematous rashes
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a 42 year old man presents with 3 weeks of worsening diarrhea, abdominal pain and fevers. he has noticed an itchy rash on his buttocks and groin area for the past 2 weeks and he has had a 15 lb weight loss. his symptoms began when he returned from El Salvador. what is the treatment of choice for this man?
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ivermectin with thiabendazole as an alternative
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a 49 year old woman presented with high fever, chills, jaundice. she is a recent immigrant from argentina. one year before she first noticed sensaiton fo fullness in right upper quadrant of abdomen. whe had been workign int he feild and breeding and raising sheepdogs. where does this worm reside in the sheepdogs?
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small bowel- they became infected from ingesting cyst containgni organs of infected sheep which are intermediate hosts.
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how long does it take for the adult forms to develop in the sheepdogs?
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32 to 80 days
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how was the sheepdog owner infected?
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ingesting eggs from food contaminated with infected dog feces
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what organism is causign the illness in the sheep dog owner?
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Echinococcus granulosus
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what happens in the human host infected with E> granulosus?
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mass develops in teh hepatic area get obstruction fo biliary duct and the space occupying mass can result in jaundice and biliary duct dilation and abdominal pain
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what coudl resutl form hyatid cyst rupture or ruptur of mass from E granulosus?
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severe allergic reaction to echinococcus antigens including anaphylaxis.
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what is teh most common treatment for hyatid cyst disease caused by E granulosus?
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surgery. and drug of choice is albendazole
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what are other sites besides the liver where you may get hyatid cyst formation with E granulosus?
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lung, brian, kidney, spleen bone and herat
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a 41 year old man present swith 4 month history of weosenign abdominal pain, diarrhea, nausea and vomiting with blood. pain is in RUQ. the man is recently immigrated from Kenya. what bug is causing this man's symptoms?
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Schistosoma mansoni
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how are humans infected with S. mansoni?
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transmitted through penetration of intact skin with infective cercariae which are released from infected snails (intermediate host) in bodies of fresh water int eh endemic countries and are free swimming in those waters.
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where do S mansoni take up residence in humans?
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veins
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in venous blood adult male and female worms mate and females lay eggs __to__weeks after cercarial penetration/
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4 to 6 weeks
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how long does the adult female worm (S mansoni) live?
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3 to 8 years and lays eggs throughout her life span.
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what is chronci schistosomiasis due to?
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immunologic reactions to Schistosoma eggs trapped in tissues...dominant immune resposne is IgE, mast cells and eosinophils--get marked eosinophilia
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the TH2 resposne contributes to profound granulomaous reaction (antigen specific T cells, macrophages and eosinophils) resulting in some of the symptoms of chronic disease. manifestations of granulomatous inflamnation fo liver presents like this?
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portal hypertension with hematemesis and hepatosplenomegaly. in latter stages of the disease fibroblasts, giant cells and B lymphocytes predominates and significant pathologic changes at that time, collagen deposisiton and fibrosis result in liver damage that may be only partially reversible
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what is treatment for S mansoni?
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praziquantel (oxamniquine is effective in areas to treat S mansoni where praziqunatel is less effective)
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