Nematodes (lecture) Flashcards
What are the two nematodes responsible for elephatiatis and their vector?
Wuchereria bancrofti
Brugia spp.
Mosquitoes
What nematode is responsible for River Blindness and its vector?
Onchocerca volvulus
Black flies
Eye worm, what is the organism and vector?
Loa loa
Chrysops flies
How do W. bancrofti and Brugia spp. cause elepahtiatis?
The adult worms obstruct the lymphatic system, causing lymphedema.
What is a common pulmonary manifestation of nematode infection?
Pulmonary eosinophilia
What is the most sensitive test for active W. bancrofti infection and special consideration for the test?
Antigen testing is best and should be done around midnight, at which point there is a peak in blood levels.
What is the DoC for lymphatic filariasis?
DEC: Diethylcarbamazene
African patient with CC of multiple “bumps” on his skin and a “hanging groin” shows cataracts. When asked about them, he explains that many people in his village go blind at an early age. What is the likely causal organism and best method of reducing the area’s incidence? How can this be confirmed? What is the treatment?
This is probably River Blindness, caused by Onchocerciasis volvulus which is transmitted by the Simulium spp. black fly. The best control would be killing the flies.
Biopsy of the cutaneous lesions would reveal worms.
Tx: Ivermectin opens Ca++ on helminths and arthropods
How does doxy address onchocerciasis infection?
It will target Wolbachia, an obligate intracellular bacteria that is commonly found in Onchocerca.
http://www.nature.com/eye/journal/v25/n3/fig_tab/eye2010192f1.html
Dx, vector, and treatment?
Loiasis is from the Loa loa worm and is transmitted via Chrysops (deer fly). Removal of the worm and DEC to address any systemic infection.
Patient with severe meningitis that does not respond to Abx treatment. LP reveals a marked increase in eosinophil. What is the most likely causal organism and vector?
Angiostrongylus cantonensis (rat lung worm) is the most common cause of eosinophilic meningitis world wide. It is carried by snails, slugs, or some shell fish.
Tx is supportive and repeated LPs to relieve pressure
What parasite causes cystic lesions in skeletal muscle? What is the most common route of transmission?
Trichinellosis is transmitted by eating meat from wild animals that contains cysts.
15 y.o. with eosinophilia and retinal lesion. She has a dog. What is the likely diagnosis? How does it go systemic?
Toxocariasis goes systemic by regurgitating the worms.
What parasitic infection a/w raw seafood is commonly responsible for food poisoning? How is in prevented?
Anisakis simplex.
Freezing meet kills it.
Name the cause: Blood microfilia at night = ? Subcutaneous nodules = ? Blood microfilia in the day = ? Muscle pain + eos = ? Eos + meningitis = ? Abdominal pain after sushi = ? Eos + incr. AST/ALT in child = ?
Lymphatic filariasis Onchocerca Loa loa Trichinella Angiostrongylus Aniskakis Visceral larva migrans (leishmaniasis)
