Microbiology- Worms 1 Flashcards
Perianal scratch mainly at night. What test to diagnose?
Pinworm - Enterobius Vermicularis
Scotch tape test
Epidemiology of pinworm?
Crowded areas - daycare
Treatment of Enterobius Vermicularis
Pyrental pamoate or Mebendazole
Enterobius Vermicularis life cycle?
Egg in anus then into mouth then larvae in small intestine and then adult in cecum
What makes up the metazoans?
Multicellular - helminths, roundworms(nematodes), flatworms (trematodes, cestodes).
Life cycle of metazoans
Eggs—>Larval—.Adult stage
What makes up the protozoans?
Single celled, flagellates ( leishmania, giardia, trypanosoma), amoeba ( Entamoeba, Naegleria)
What is a reservoir
host which maintains the parasite in natureas a source of transmission
What is a definitive host
host where sexual reproduction takes place
What is an intermediate host
host where development occurs and NOT sexual reproduction
What is accidental host
host where parasite cannot complete its life cycle
Life Cycle of Whipworm and what stage is infective
Eggs in soil–>Swallowed–>Attach to gut wall–>Eggs excreted( not infective)–.Embryonate in soil (infective)
Clinical presentation of whipworm and treatment
Asymptomatic, chronic blood loss like inflammatory bowel disease. Mebendazoel or Albendazole
Life Cycle of Hookworm
Eggs in feceas->Rhabtiform Larva hatches->Filariform larvae penetrates skin->Adults in small intestine
Hookworm Name and pathogenesis and treatment
Necator americanus. Have teeth to eat and produce anticoagulant. Mebendazole
Effects of Hookworm infection
Iron deficiency
Ascaris Lumbricoides. Features, Diagnosis. Treatment
Eggs irregular coating, intestinal obstruction, Eggs in stool. Pyrantel pamoate/Mebendazole
Toxocara canis ( visceral larva migrans)
Eggs from dog or cat roundworm ingested. Larva peetrate and go to liver, lungs and eyes causing inflammation. Human is accidental host
Toxocara canis ( cutaneous larva migrans)
Larva penetrates skin, migrates in subcutaneous tissue and cause inflammation
Worm in sputum of immuno-comprised host
Strongyloides stercoralis. Infective stage is filariform larvae
Diagnostic stage Strongyloide stercoralis
Rabtidiform larvae
Infective stage of Strongyloide stercoralis
Filariform larvae
What organism does auto-infection? Explain
Strongyloides stercoralis - Filariform in blood gets to lungs, then is swallowed into small intestine to become an adult. Eggs laid and Rabtidiform in large intestines become filariform larvae and penetrate the skin to get into blood and then lungs
Diagnosis of Strongyloides
Serology
Loeffler syndrome
Lung migration by Strongyloides
Treatment
Ivermectin, Albendazole
Aopted child from endemic country with eosinophilia
Strongyloides stercoralis
Hunter with fever, periorbital edema, abdominal pain and diarrhea
Trichinella spiralis
Infective Stage and Diagnostic stage of Trichinella?
Encysted larvae in straited muscle for both
Sources of infection with Trichinella spiralis
Poorly cooked meat, pork
Source of Wuchereria bancrofti (Filariasis)
Mosquito
What stage is diagnostic for Wuchereria bancrofti (Filariasis)
Microfilaria in blood stream at night, serology for Dx. Adults in lymphatics
Pathophysiology of Wuchereria bancrofti (Filariasis)
Adults die in lymphatics, calcifying and causing blockages resulting in elephantiasis.
Treatment of Wuchereria bancrofti (Filariasis)
Diethylcarbamazine
Organism causing multiple holes in a brain from a person in a rural area
TB or tapeworm( neurocysticercosis)
Parts of a tapeworm and sex
Head with sucking ( scolex), proglottids ( segments with uteri) and hermaphrodites
Mode of transmission for tapeworms ( 2)
Cattle ( T. saginata), Pigs ( T. solium)
Diagnostic stage and Infective stage of tapeworms
Eggs or gravid proglottids in stool and Cysticerci
What causes neurocysticercosis
T. solium - neurologic, ocular or muscular
Treatment
Praziquantel and confirm with scolex
Echinococcus granulosus definitive host
Dogs, Wolves, Coyotes
Echinococcus granulosus intermediate host
sheep, goats
Echinococcus granulosus diagnostic stage
Hydadid cyst in liver or lung
Echinococcus granulosus infective stage
Embryonated eggs in feces
Pathophysiology of Hydatid cyst
Liver cyst so appears as slow growing liver cancer.
Treatment of Echinococcus granulosus
Mebendazole and Surgery. For surgery kill with ethanol first before removal to prevent anaphylaxis on rupture
Intermediate host of Schistosomiasis
Water snail
Infective stage of Schistosomiasis
Cercariae
Diagnostic stages
Feceas - S. mansoni and japonicum. Urine- S. hematobium
Organism with many nuclei and RBCs in it
Entamoeba histolytica
Flask shape ulcers in large intestine
E. histolytica
Infective stage of E. histolytica
Matured cysts and trophozoites in stools
Diagnostic stage of E. histolytica
Matured cysts, trophozoite,
Diagnosis of E. Histolytica
Cysts in stools, serology, antigen
Treatment of E. Histolytica
Metronidazole for symptomatic infection, Paromomycin for eradication of luminal carriage
Fresh water infection or tapwater in neti pots that migrates to the brain ( rapidly fatal meningoencephalitis)
Naegleria fowleri
Treatment of Naegleria fowleri
Amphotericin B against in vitro infection
Strawberry cervix with frothy vaginal discharge
Trichomonas ( no cysts formed so cannot live outside of humans)
Life Cycle of Trichomonas
Just human beings. Cannot survive out of humans. Divides by binary fission
Diagnosis of Trichomonas
Trophoziotes on wet mount (motile)
Trophozoites with 2 nuceil, bilateral symmetry and Cysts with 4 nuclei
Giardia
Foul smelling, fatty diarrhea
Giardia
Diagnosis of Giardia
Cysts and trophozoites in stools
Treatment of Giardia
Metronidazole
Infective stage of Giardia
Cysts in food, water and stools
Diagnosis of Giardia
Trophozoites in stool and cysts
How Giardia reproduces
Longitudinal binary fission
