Micro - Parasitology (Worms & Parasite hints) Flashcards
Pg. 151-152 Sections include: Nematodes (roundworms) Nematode routes of infection Cestodes (tapeworms) Trematodes (flukes) Parasite hints
What is another name for roundworms?
Nematodes
What are 4 examples of intestinal Nematodes? Where applicable, give common name in addition to genus species names.
(1) Enterobius vermicularis (pinworm) (2) Ascaris lumbricoides (giant roundworm) (3) Strongyloides stercoralis (4) Ancylostoma dudoenale, Necator americanus (hookworms)
What is the genus & species for pinworm? How is it transmitted?
Enterobius vermicularis; Fecal-oral
What disease/symptoms does Enterobius vermicularis (pinworm) cause? How is it diagnosed? How is it treated?
Intestinal infection causing anal pruritus (diagnosed via the Scotch Tape test); Bendazoles or pyrantel pamoate; Think: “worms are BENDy; treat with meBENDazole”
What is the genus & species for giant roundworm? How is it transmitted? What can be seen under microscope?
Ascaris lumbricoides; Fecal-oral, eggs visible in feces under microscope
What disease is caused by Ascaris lumbricoides (giant roundworm)? How is it treated?
Intestinal infection; Bendazoles or pyrantel pamoate
How is Strongyloides stercoralis transmitted?
Larvae in soil penetrate the skin
What disease/symptoms does Strongyloides stercoralis cause? How is it treated?
Intestinal infection causing vomiting, diarrhea, anemia; Ivermectin or albendazole
What are 2 genuses and species for hookworms? How are they transmitted?
Ancylostoma dudodenale, Necator americanus; Larvae penetrate skin
What disease do hookworms (Ancylostoma duodenale & Necator americanus) cause? How is it treated?
Intestinal infection causing anemia by sucking blood from intestinal walls; Bendazoles or pyrantel pamoate
What are 4 examples of tissue Nematodes?
(1) Onchocerca volvulus (2) Loa loa (3) Wuchereria bancrofti (4) Toxocara canis
How is Onchocerca volvulus transmitted? What disease does it cause? What is a possible side reaction? How is it treated?
Female blackfly bite; Tissue disease - Hyperpigmented skin and river blindness (Think: “BLACK flies, BLACK skin nodules, BLACK sight”); Allergic reaction to microfilaria possible; Ivermectin (Think: “IVERmectin for rIVER blindness”)
How is Loa loa transmitted? What disease does it cause? How is it treated?
Deer fly, horse fly, mango fly; Tissue disease - Swelling in skin, worm in conjuctiva; Diethylcarbamazine
How is Wuchereria bancrofti transmitted? How long after the bite does it take to become symptomatic?
Female mosquito; takes 9 mo-1 yr after bite to become symptomatic
What disease does Wuchereria bancrofti cause? How is it treated?
Tissue disease - Blocks lymphatic vessels: elephantiasis; Diethylcarabamazine
How is Toxocara canis transmitted? What disease does it cause? How is it treated?
Fecal-oral; Tissue disease - Visceral larva migrans; Albendazole or mebendazole
What are the 3 main routes for infection by Nematodes. Which Nematodes take which route?
(1) Ingested - Enterobius, Ascaris, Trichinella (Think: “you’ll get isck if you EAT these!”) (2) Cutaneous - Strongyloides, Ancylostoma, Necator (Think: “these get into your feet from the SANd”) (3) Bites - Loa loa, Onchocerca volvulus, Wuchereria bancrofti (Think: “lay LOW to avoid getting bites”)
What is another name for tapeworms? What are 3 examples?
Cestodes; (1) Taenia solium (2) Diphyllobothrium latum (3) Echinococcus granulosus
How is Taenia solium transmitted? What disease(s) does it cause? What is/are its treatment(s)?
(1) Ingestion of larvae encysted in undercooked pork –> Intestinal infection –> Tx: Praziquantel (2) Ingestion of eggs –> Cysticercosis, neurocysticercosis –> Tx: Praziquantel; Albendazole for neurocysticercosis
How is Diphyllobothrium latum transmitted? What disease does it cause? How is it treated?
Ingestion of larvae from raw freshwater fish; Vitamin B12 deficiency (tapeworm competes for B12 in intestine) –> anemia; Praziquantel
How is Echinococcus granulosus transmitted? What disease does it cause? How is this managed clinically, and why? How is it treated?
Ingestion of eggs from dog feces; Hydatid cysts in liver, causing anaphylaxis if antigens released (surgeons preinject with ethanol to kill cysts before removal); -bendazoles
What is another name for flukes? What are 2 examples?
Trematodes; (1) Schistosoma (2) Clonorchis sinensis
How is Schistosoma transmitted? What disease does it cause? How is it treated?
Snails are host, cercariae penetrate skin of humans; Liver and spleen granulomas, fibrosis, and inflammation; Praziquantel
What species of Schistosoma poses a particularly important risk following chronic infection? What is that risk?
Chronic infection with S. haematobium can lead to squamous cell carcinoma of bladder
How is Clonorchis sinensis transmitted? What disease does it cause? How is it treated?
Undercooked fish; Biliary tract inflammation –> pigmented gallstones; Praziquantel
Again, what disease does Clonorchis sinensis cause? With what kind of risk is it associated?
Biliary tract inflammation –> pigmented gallstones; Associated with cholangiocarcinoma
If your patient has brain cysts and seizures, which parasite is most likely?
Taenia solium (cysticercosis)
If your patient has liver (hydatid) cysts, which parasite is most likely?
Echinococcus granulosus
If your patient has Vitamin B12 deficiency, which parasite is most likely?
Diphyllobothrium latum
If your patient has biliary tract disease and/or cholangiocarcinoma, which parasite is most likely?
Clonorchis sinensis
If your patient has portal hypertension, which parasite(s) is (are) most likely?
Schistosoma mansoni, Schistosoma japonicum
If your patient has hematuria and/or bladder cancer, which parasite is most likely?
Schistosoma haematobium
If your patient has microcytic anemia, which parasite(s) is (are) most likely?
(Hookworms) Ancylostoma, Necator
If your patient has perianal pruritus, which parasite is most likely?
Enterobius
