helminths Flashcards
Helminthes are divided to
- Nematodes (roundworms)
- Cestodes (tapeworms)
- Trematodes (flukes)
Antihelmintihic therapy - drugs
- Menbendazole
- Pyrantel paomate
- Ivermectin
- Diethylacarbamazine
- Praziquantel
Nematodes (roundworms) bugs and divisions
intestinal:
- Enterobius vermcularis (pinworm)
- Ascaris Lumbricoides (giant roundworm)
- strongyloides stercoralis
- Ancylostomas duodenale (hookworm)
- Necator americans (hookworm)
- Trichinella spiralis
tissue: - ochocerca vovlulus
- loa loa
- wucheria bancrofti
- Toxocara canis
Enterobius vermcularis is AKA / transmission / disease / treatment / diagnosis
pinworm / fecal oral / intestinal infection causing anal pruritus / bendazoles / seeing egg via the tape test
Ascaris lumbricoides is AKA / transmission / disease / treatment / diagnosis
giant roundworm / fecal oral / intestinal infection with possible obstruction at ileocecal valve / bendazoles / egg visible in feces under microscope
Strogyloides stercoralis - transmission / disease / treatment
- Larvae in soil penetrate the skin
- intestinal infection causing vomiting, diarrhea, epigastric pain (may feel like peptic ulcer)
- treatment: bendazoles or ivemectin
Ancylostomas duodenale and Necator americans (hookworms) - transmission
larvae penetrate skin
Ancylostomas duodenale and Necator americans (hookworms) - disease
intestinal infection causing microcytic anemia by sucking blood from intestinal walls
Cutaneous lavra migrans
Cutaneous lavra migrans?
caused by Hookworms: pruritic, serpiginous rash from walking barefoot on contaminated beach
Ancylostomas duodenale and Necator americans (hookworms) - treatment
bendazoles or pyrantel pamoate
tissue nematodes (roundworms) - bugs
- onchocerca vovlulus
- loa loa
- wurcheria bancrofti
- toxocara canis
onchocerca vovlulus - transmission and treatment
female blackfly bite
ivermectin
onchocerca vovlulus disease
- hyperpigmented skin
- river blindness skin nobules
- allergic reaction to microfilaria possible
- loss of elastic fibers
Wucheria bancrofti - transmission
female mosquito
Wucheria bancrofti - disease and symptoms (and mechanism)
ELEPHANTIASIS: worms block lymphatic vessels –> edema (takes 9 months - 1 yr after bite to become symptomatic)
Wucheria bancrofti - treatment
diethylcarbamazine
loa loa - disease / transmission / treatment
swelling in skin, worm in conjunctiva
- deer fly
- horse fly
- mango fly
- diethylcarbamazine
Toxocara canis - disease and mechanism
visceral lavra migrans: nematodes migrate to bood through intestinal wall causing inflammation and damage –> organs frequently affected include the heart (myocarditis) liver and CNS (seizure and coma)
trichinella spiralis - transmission / treatment
fecal oral
undercooked meat (eps pork)
- Bendazole
trichinella spiralis - disease (mechanism and symptoms)
intestinal infection: lavrae enter bloodstream and encyst in striated muscle -> inflammation of muscle
Trichinosis –> fever, vomiting, nausea, periorbital edema, myalgias
Nematode routes of infection (and bugs) (generally)
- ingested –> enterobius, ascaris, toxocara, trichinella
- cutaneous –> strongyloide, ancylostoma, necator
- Bites –> Loa Loa, onchocerca vovlulus, Wuchereria bancrofti
Cestodes (tapeworms) - bugs
- Taenia solium
- Diphyllobothrium latum
- Echinococcus granulosus
Taenia solium - transmission
- ingestion of larvae encysted in undercooked pork
- ingestion of eggs contaminated with human feces
- Central + south america, africa, asia
Taenia solium - disease
if ingestion of eggs –> Cysticercosis, neurocysticercosis
if ingestion of larvae encysted in undercooked pork –> intestinal infection
Taenia solium - treatment
praziquantel (for intestinal infection and cysticercosis)
albendazole (for neurocysticercosis)
cysticercosis - mechanism and presentation
cysticerci in skeletal muscle, brain (neurocysticercosis), eye (blindness)
neurocysticercosis - presentation and treatment
1. seizures 2. focal neurological deficit hydrocephalus treatment: 1. seizure/ICH management 2. antiparasaitic: albendazole 3. corticosteroids
Diphyllobothrium latum - transmission / treatment
ingestion of lavrae from raw freshwater fish
- praziquantel
Echinococcus granulosus - transmission / host
ingestion of eggs from dog feces
Sheep are an intermediate host
Echinococcus granulosus - treatment
albendazole
percutaneous therapy (if more than 5 cm or septations)
- if rupture: surgery
Cestodes are divided to … (and treatment)
- Taenia solium –> praziquantel (for intestinal infection and cysticercosis), albendazole (for neurocysticercosis)
- Diphyllobothrium latum –> prazuquantel
- Echinococcus granulosus –> Albendazole,
hydatid cysts injected with ethanol or hypertonic saline to kill daughter cysts before removal
Trematodes (flukes) - bugs / AKA
Flukes:
- Schistosoma
- Clonorchis sinensis
Schistosoma - transmission
snail are host
cercarieae penetrate skin of humans
Schistosoma - bugs and treatment
- S. mansoni
- S. japonicum
- S. haematobium
praziquantel
Schistosoma - disease
Liver and spleen enlargement (S. mansoni S. japonicum), fibrosis and inflammation, portal hypertension
chronic infection with S. haematobium –> SCC of the bladder and pulmonary hypertension
Clonorchis sinensis - transmission
undercooked fish
Clonorchis sinensis - disease
Biliary tract inflammation –> pigmented gallstones
associated with cholangiocarcinoma
Trematodes (flukes) - bugs and treatment
- Schistosoma
- Clonorchis sinensis
PRAZIQUANTEL
Parasites hints - Brain cysts and seizures
Taenia solium (neurocysticercosis)
Parasites hints - Biliary tract disease
chlonarchis siensis
Cutaneous Lavra migrans - epidemiology
- Hookworm Lavrae (dog or cat)
- Humans are incidental hosts
- Barefoot contact with contaminated sand or soil
cutaneous lavra migrans - clinical manifestation
- 1ry lower extr
- cutaneous (deeper is rare)
- Erythematus, pruritic papule at site of entry
- intensely pruritic migrating, serpiginous, reddish-brown tracks
cutaneous lavra migrans - diagnosis / treatment
- history of clinical findings
- eosinophils usually are normal
treatment: antihelmintic (eg. ivermectin)
neurocysticercosis - diagnosis
CT/MRI - cysts: hypodense, enchancement/edema or Ca2+
hydatid cyst - CT
egg shell calcification
Mycobact avium - manifestations
nonspecific (fever, cough, abd pain, diarrhea, night sweats, weight loss) in the presence of splenomegaly and an elevated alkaline phosphate level
