Parasite infections of skin and soft tissue Flashcards
What organisms cause cutaneous leishmaniasis?
L. major, L. tropica, L. mexicana
What form of leishmaniasis is found inside infected individuals?
Amastigote (intracellular)
Are antibodies useful against leishmaniasis?
No (intracellular pathogens)
What type of immunity is required to resolve leishmaniasis infection?
Cell mediated immunity - IFNy activation of macrophages
What is the cause of river blindness?
Onchocerca volvulus
In river blindness, which form of the nematode does the most damage?
Migrating and dying microfilariae
How is mansonella transmitted?
Bite of infected midge
How is dracunculosis transmitted?
Ingestion of infected copepods in water
What is the pathogenesis of dracunculosis?
Larvae penetrate intestine and enter subcutaneous tissue - maturation takes about 1 year
What is the cause of cutaneous larval migrans?
Ancylostoma (hookworms) that normally infect dogs or cats
Patients with pertinent clinical symptoms and travel history to the Caribbean would indicate which potential infection?
Cutaneous larval migrans
What is the appearance of scabies infection?
Short, serpentine, slightly raised, cutaneous tracts along which the mites have burrowed
What causes Norwegian (crusted) scabies?
Hyperinfection of scabies mites
What is the cause of Myiasis?
Dermatobia hominis - botfly
How is Chaga’s disease transmitted?
Bite / defecation of reduviid bug
What is the symptamology of Chaga’s disease?
- Development of chagoma - Romana’s sign 2. Acute phase - fever, malaise, myalgia, hepatosplenomegaly
Trichinosis is associated with what practice?
Eating undercooked meat (pork) containing encysted larvae
Where do trichinella spiralis larvae encyst in the body?
WITHIN striated muscle cells
What clinical symptoms aid in diagnosis of trichinosis?
Eosinophilia, elevated CPK, LDH, dietary history, periorbital edema
How is loiasis transmitted?
Bite of mango fly
How is loiasis diagnosed?
Observation of microfilariae in bloodstream, eosinophilia
How are lung flukes transmitted?
Ingestion of fresh water crabs or crayfish
Which parasitic infection is associated with “rusty sputum”?
Lung fluke
