Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/16

Click to flip

16 Cards in this Set

  • Front
  • Back
Filariae
- Blood and tissue namatodes
- long, slender roundworms
- may live 10-15 years and they release microfilariae which live in the blood or skin and are the infective stage for the insect intermediate host
Wuchereria bancrofti Basic Info
- elephantiasis or Lymphatic filariasis - gross swelling of limbs - lymphatic ducts/nodes blocked and scarred
- develops after years of chronic and repeated infection
-in africa, asia, latin america, caribbean
Wuchereria bancrofti Infection
- Adult worms live in lymphatics and microfilariae in blood are ingested by the mosquito
- mature in mosquito and microfilariae can be transmitted
- do nocturnal periodicity, where they circulate at night, when vector is active, and remain in lung caps in day
- south pacific has "day-biters"
- Travelers may have rapid progression and tropical pulmonary eosinophilia w/ fever, eosinophilia, respiratory symptoms but no microfilaremia
- prevent w/ mosquito abatement and early treatment
Wuchereria bancrofti Disease
- chronic, cumulative disease w/ few symptoms at first
- damage from inflam which varies among individuals
- microfilariae can be detected in blood at night when asymptomatic
- After 8 to 16 months, painful lymphangitis, esp in groin w/ recurring fever
- Also eosinophilia
- can lead to swelling of limbs or scrotum(hydrocoele), complete blockage
- if elephantiasis no circulating microfilariae
Onchocerca volvulus Basic Info
- tissue nematode, river blindness
- Adults live in nodules under the skin, make microfilariae that migrate in skin
- micros transmitted by bite of black fly that cant fly far from fast-flowing water
- tropical Africa,Central/south America
Onchocerca volvulus Infection
- Micro migrating in skin ->
intense itching -> 2o inf
- months to years, then skin atrophy and degeneration (pachydermia)
- may get eye -> blindness
Onchocerca volvulus Diagnosis and Treatment
- taking superficial skin snips,
place in water, and examine for motile micros
- If nodules, biopsy or nodulectomy
- control w/ Ivermectin
Taenia saginata
- Cestodes or tapeworms
- adults live in human GI
- eggs from feces may be ingested by cow, hatch in their intestine and migrate to muscle to form cysticerci (larval tapeworm in fluid sac
- ingest undercooked meat and cysticercus elongates into adult w/ segments
- Eggs form in post proglottids, detach, then passed w/ feces
Taenia solium
- Cestodes or tapeworms
- adults live in human GI
- eggs from feces may be ingested by pig, hatch in their intestine and migrate to muscle to form cysticerci (larval tapeworm in fluid sac
- ingest undercooked meat and cysticercus elongates into adult w/ segments
- Eggs form in post proglottids, detach, then passed w/ feces
- can cause cysticercosis in humans
- in muscles its ok, in brain heart lungs eye its not
- human to human transmission also possible(fecal-oral)
Tapeworms
- rarly cause symptoms
- no gut or digestive enzymes - absorb nutrients from host
- may be noticed if a proglottid is passed in the feces
- Diagnosis w/ feces for eggs and if proglottid, inject uterus with India ink to show the uterine branches (fewer in solium)
- The scolex (“head”) of solium has armed rostellum (circle of hooks) in addition to the four suckers
Cysticercosis
- severe tapeworm disease
- can cause seizures, even w/out an adult tapeworm
- symptoms may appear long after exposure to the eggs
- diagnose w/ Abs in the blood or CSF
- cysticerci are seldom found, but in muscle there are calcium deposits(seen in radiograph)
- pork tapeworm most common in Mexico, Chile, E Europe, S Africa, China, and Indonesia
- Control by sanitary sewage, thorough cooking & inspection
trematodes
- flukes - flatworms
- live in GI, bile ducts, lungs, BVs
- complicated life cycles - asexual in snail and sexual in humans
Schistosomes Basic info
- bloodfluke (trematodes)
- mansoni cuases intestinal infection - in Africa, South America, and Caribbean
- japonicum causes intestinal infection - in Far East
- hematobium causes urinary infections in Africa
Schistosomes Infection
- live 10 yrs, male and female permanently coupled in veins of the GI or bladder
- pass lots of spined eggs -> tissue damage and symptoms
- eggs get into the feces or urine and hatch to release a motile miracidium when released
- must infect correct snail ->(asexual) makes free-swimming cercariae than can penetrate human skin causin swimmer’s itch
- developing larvae migrate via lymphatics and lungs to the venules and grow to adults
Schistosomes Disease
- mainly in rural areas where sewage enters water (snail can meet poop)
- Light infections may be asymptomatic after swimmer’s itch - sometimes fever
- heavy/repeat infection-lots of eggs-> granulomatous rxn and fibrosis
- w/ mansoni, periportal fibrosis in the liver -> portal hypertension - may have distension of esophagus veins
- w/ hematobium, obstruction of the ureters and 2o UTI, granulomas in the bladder, or bladder carcinoma.
Schistosomes Diagnosis and Treatment
- detecting eggs in the feces or urine
- If found early and the patient, the chronic stages are avoided
- Control via sanitation, look out for snails in waterways, treat infected persons