What are considered the “most significant diseases in the world”?
- intestinal: worms, bacteria, viral diarrheas
- malaria
- Tb
- Schistosomiasis
- Leishmaniasis
- HIV
- streptococci-staphylococci
T/F- nematodes are round worms and include intestinal and non-intestinal species. They have two sexes.
True
T/F- cestodes are flat worms and have two sexes
False, they are flat worms but are hermaphrodites
What are trematodes also known as? Do they have two different sexes?
Flukes
Yes
A child is infected with Enterobius vermicularis, what test would you do at night to find the eggs?
scotch tape test
What is Enterobius vermicularis commonly known as and how many infections does it cause in the united states?
pin worm
-30-40 million
Describe the life cycle of enterobius vermicularis
- eggs eaten or breathed in
- hatch in small intestine
- larvae move to large intestine
- mature in 2-4 weeks, mate
- female migrates out of anus at night to lay eggs
- eggs rupture when exposed to air and cause itching
What are the symptoms and consequences of Enterobius vermicularis infection?
- itching
- occasionally appendicitis
- peritoneal granulomas (rare)
- UTI’s (rare)
T/F- There are protective immune responses against Enterobius vermicularis
False. Although there can be type I allergic response (itching)
What type of worm does the Ascaris lumbricoides species resemble? and where is it found?
“earthworm like”
tropical areas including Southeastern US
Describe the life cycle of Ascaris lumbricoides
- eggs are eaten
- hatch in small intestine
- larvae invades small intestine
- enter lymphatics and portal blood
- travel to liver, then lungs
- coughed up, swallowed again
- sexually mature in the small intestine and mate
- produce eggs which pass out in feces
- eggs must embryonate in warm moist soil
What are the clinical features of Ascaris lumbricoides?
- patchy pneumonia (Loeffler’s syndrome)- tracheobronchitis, SOB, eosinophilia, papular/urticarial rash
- biliary obstruction
- intestinal cramping
- liver granulomas (rare)
T/F- Trichuris trichiura is known as whip worm and produces barrel shaped eggs with bipolar plugs, and occurs in the Southeast US.
true
Describe the life cycle of Trichuris trichiura
- eggs are eaten
- hatch in small intestine
- larvae damage villi, move to large intestine where they mature
- Eggs pass into feces and are infective in warm soil
Clinical features of a Trichuris trichiura infection?
- mucosal damage/bleeding
- anemia, growth retardation
- rectal prolapse
What are the “old world” and “new world” species of hookworms?
old world: Ancylostoma duodenale
New world: Necator americanus
T/F- hookworms attach to the small intestine and suck blood. They are commonly found in Southeastern US
True
Describe the life cycle of hookworms
- filamentous larvae develop in soil
- penetrate human skin as dew itch
- spread to lungs through blood
- break into alveoli and travel up respiratory tree
- swallowed
- mature in small intestine
- eggs pass in feces, hatch into larvae
T/F- clinical features of hookworm infection include: Loeffler’s syndrome, hepatosplenomegaly, abdominal pain, diarrhea, weight loss, anemia, mental/physical retardation
true
T/F- Strongyloides stercoralis are 2mm in length, have a life cycle similar to hookworms without dew itch, and are found in the Southwestern United states
Found in southeastern US, everything else is true
T/F- health care workers are often infected with Strongyloides stercoralis
true
Clinical features of Strongyloides stercoralis?
- Pneumonitis w/ Loeffler’s syndrome in lung stage
- abdominal pain, diarrhea
- malabsorption (mental/growth retardation)
- risk of gram negative shock
A 3 yr old girl has intense butt scratching and inability to sleep, mother has same symptoms. Scotch tape test is performed and eggs are found. What is it? What would you treat it with?
Pin worms (enterobius vermicularis) Treat with Mebendazole
