Micro Exam 4 Cue Cards

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Micro Exam 4 Cue Cards
2013-03-26 18:21:22
Micro Exam Cue Cards

Micro Exam 4 Cue Cards
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  1. What is the agent of Cysticercosis?
    Taenia solium
  2. What is the causative agent of fish tapeworm?
    Diphyllobothrium latum
  3. Which tapeworm is characterized by its wide proglottids and rosette shaped uterus?
    Diphyllobothrium latum
  4. Name a tapeworm that grows to remarkable lengths-up to 60 feet long.
    Diphyllobothrium latum
  5. The scolex of this tapeworm is described as having two leaf-shaped suckers.
    Diphyllobothrium latum
  6. Exhaustion of vitamin B12 is possible over many years, resulting in megaloblastic anemia. This occurs in less than 2% of patients. Name the tapeworm associated with this condition.
    Diphyllobothrium latum
  7. Name the drug used to treat Diphyllobothrium latum.
  8. Name the causative agent of beef tapeworm.
    Taenia saginata
  9. The tapeworm produces mature proglottids with greater than 13 lateral branches in the uterus.
    Taenia saginata
  10. This species of Taenia has a scolex characterized by having 4 suckers, and no hooklets.
    Taenia saginata
  11. Eggs produced by this species of Taenia will NOT hatch in the human intestine.
    Taenia saginata
  12. This species of Taenia can have 1000-2000 proglottids, each producing up to 100,000 eggs.
    Taenia saginata
  13. This species of Taenia can have an average of 1000 proglottids, each producing up to 50,000 eggs.
    Taenia solium
  14. Eggs of this species of Taenia WILL hatch in the human intestine. The oncosphere from this egg will penetrate the intestinal wall, migrate to soft tissues including the brain.
    Taenia solium
  15. What is the leading cause of epilepsy in children in Los Angeles county?
    Neurocysticercosis caused by Taenia solium
  16. Name the drug of choice for treatment of Taenia infections.
  17. The scolex of this species of Taenia is characterized by having 4 suckers and row of hooklets that are used to attach to the intestine.
    Taenia solium
  18. Name the causative agent of dog tapeworm.
    Dipylidium caninum
  19. Humans acquire this tapeworm infection by ingesting arthropods (often fleas) which contain the cysticercoid.
    Dipylidium caninum
  20. Proglottids of this tapeworm separate from the strobila and can migrate out of the anus. Clinicians might encounter an anxious mother who reports finding "rice grain or cucumber seed sized worms" in her childs diaper.
    Dipylidium caninum
  21. This tapeworm produces egg packets containing embryonated eggs that are ingested by arthropods.
    Dipylidium caninum
  22. The intermediate host of this tapeworm is an arthropod that ingests the eggs, which hatch an onchosphere, which migrates to the body cavity of the arthropod and develops into a cysticercoid larvae.
    Dipylidium caninum
  23. Name the treatment of choice for Dipylidium caninum.
  24. This small tapeworm has only three proglottids, lives in the intestine of canines, and is responsible for formation of hydatid cysts in humans.
    Echinococcus granulosus
  25. Dogs are infected with this tapeworm when they eat infected intermediate hosts, usually sheep, goat, swine, cattle etc.
    Echinococcus granulosus
  26. This tapeworm infection may first be noticed as a large space-occupying lesion on an xray or other image.
    Echinococcus granulosus
  27. These tapeworms are acquired by the accidental ingestion of rodent droppings containing infective eggs. Cause mild symptoms (unless heavily infected). Are primarily parasites of children
    • Hymenolepsis diminuta
    • Hymenolepis nana
  28. Infection with this cestode is acquired by eating raw or poorly cooked fish containing plerocercoid larvae.
    Diphyllobothrium latum
  29. Infection with this cestode may first be detected as a "bulls eye" lesion on xray.
    Taenia solium
  30. Embryonated eggs of this cestode release a coracidium which is eaten by crustaceans. There they develop to a precercoid larvae.
    Diphyllobothrium latum
  31. Term synonymous with Diphyllobothrium latum plerocercoid larvae. This term is often used to describe infection with which cestode?
    • Sparganum
    • Sparganosis
  32. How do children acquire infection with dog tapeworm?
    Ingestion of fleas containing the cysticercoid.
  33. What behavior might the family dog exhibit if infected with dog tapeworm?
    Dogs may scrape their anal region across grass or carpet to relieve itching.
  34. Infection with this cestode features production of protoscoleces inside a fluid filled cyst.
    Echinococcus granulosus
  35. True/False. Fluid from a hydatid cyst is highly toxic and can cause anaphylactic shock if the cyst ruptures.
  36. Detection of this cestode might occur during routine xray for other purposes. Examination of the image would reveal a large space-occupying lesion.
    Echinococcus granulosus
  37. The definitive hosts of these cestodes are rodents.
    • Hymenolepis diminuta
    • Hymenolepis nana
  38. True/False. Eggs of Hymenolepis diminuta are distinguised from eggs of Hymenolepis nana by the presence of polar filaments in the H. nana egg.
    • True.
    • Some refer to their grandmother as "nana". Picture your grandmother (nana) with polar filaments or a mustache!
  39. True/False. Humans are accidentally infected with Hymenolepis diminuta by the accidental ingestion of rodent feces.
    • False.
    • Humans are infected with Hymenolepis diminuta by ingestion of an insect harboring the cysticercoid larvae.
  40. Humans can acquire this rodent tapeworm either by ingestion of insects containing cysticercoid larvae or direct ingestion of embryonated eggs in contaminated food or water.
    Hymenolepis nana
  41. Which Taenia is characterized as having an "armed" rostellum?
    Taenia solium
  42. An anxious mother brings her baby to you and describes small motile seed-like white "things" in the child's diaper. What item might you add to your differential diagnosis from this information? What question(s) might you ask the mother to help verify your suspicions? What would be a good test to order?
    • Dipylidium caninum might be the cause.
    • Could ask if there is a dog in the family.
    • Request stool from child and examination for O&P.
  43. You examine tapeworm segments passed by a patient, and notice that the segments are wider than they are long. Which species does this suggest to you?
    Diphyllobothrium latum
  44. Name parasitic infections (genus and species) one might acquire by eating raw or poorly cooked pork.
    • Taenia solium
    • Trichinella spiralis
    • Cysticercosis (larval form Taenia solium)
  45. Name parasitic infection(s) genus and species one might acquire by eating raw or poorly cooked beef.
    Taenia saginata
  46. What is the genus and species of the dwarf tapeworm?
    Hymenolepis nana
  47. True/False. Parasites are microscopic organisms that live inside blood cells of the host. No other forms exist.
    • False.
    • Parasites have remarkable ranges of size and shape (over 30 ft to microscopic forms in cells).
  48. Definition: one population (or individual) gains from the association and the other is neither harmed nor benefited.
  49. Definition: a reinfection in which the patient is his own best source of infection from a source already present in the body.
  50. Definition: an abnormal frequency and liquidity of fecal discharges.
  51. Definition: a parasite that lives on the outsides of the body of the host infestation.
  52. Definition: the formation and accumulation of an abnormally large number of eosinophils in the blood.
  53. Definition: the host which harbors the adult or sexually reproducing stages of a parasite.
    Definitive host
  54. Definition: the host which harbors the immature, larval, or asexually reproducing forms of the parasite.
    Intermediate host
  55. Definition: an animal which replaces man as a host in the life cycle of a parasite.
    Reservoir host
  56. Definition: symbiosis in which both populations (or individuals) gain from the association and are unable to survive without it.
  57. Definition: symbiosis in which one population (or individual) adversely affects the other, but cannot live without it (infection or infestation with parasites).
  58. Definition: in parasitology, the living together or close association of two dissimilar organisms, each of the organisms being known as a symbiont. The association may be beneficial to both (mutualism), beneficial to one without effect on the other (commensalism), beneficial to one and detrimental to the other (parasitism), detrimental to one without effect on the other (amensalism), or detrimental to both (synnecrosis).
  59. Definition: a carrier, usually an arthropod, which transmits an infective agent from one host to another.
  60. Definition: the degree of pathogenicity of a microorganism as indicated by the severity of the disease produced and its ability to invade the tissues of a host. It is measure experimentally by the median lethal dose (LD50) or median infection dose (ID50). By extension, the competence of any infectious agent to produce pathologic effects.
  61. Name three methods by which one may acquire a parasitic infection.
    • Ingestion of the parasite
    • Active penetration of the parasite
    • Infection by a vector
  62. True/False. All intestinal parasites have a similar life cycle. One swallows the egg, eggs hatch and the parasite lives in the intestinal tract.
    • False.
    • Some parasites have a simple "hand to mouth" life cycle, but others must migrate through the body, notably lungs, to complete their life cycle.
  63. True/False. Young, healthy adults (soldiers) are not a t much risk of acquiring parasitic infections because they are in excellent physical condition and good general health.
    • False.
    • Parasites can infect anyone who is exposed. Those victims who are physically debilitated or have poor immune systems may fare worse, but all can be infected.
  64. True/False. Diarrhea is a minor side effect of some parasitic infections, and can be ignored since it is self-limiting.
    • False.
    • Diarrhea can lead to dehydration and fluids must be replaced. This can lead to debilitation and shock in extreme cases.
  65. Name some of the damaging effects a parasite can have on its host.
    • Blood loss
    • Diarrhea & dehydration
    • Immune response (can damage host)
    • Tissue destruction (parasite eats tissue)
    • Feel poorly, loss of appetite, loss of nutrition (indirectly)
  66. Which class of white blood cells may show increased numbers in parasitic infections?
  67. True/False. Indirect evidence of parasitic infections obtained by serological testing is the best method of diagnosis.
    • False.
    • Direct evidence is the best method. Direct evidence includes identification of a passed worm, microscopic examination of stool to identify parasite eggs or microscopic protozoa, etc.
  68. You have a patient who has a lab result showing a titer of 1:128. What does this mean?
    Lab has made serial dilutions of the patient's serum, and tested each dilution. The last dilution that showed a positive result was the tube containing serum diluted 128 times.
  69. What is the primary lab instrument used to diagnose parasitic infections?
    Microscope and really trained eyeballs.
  70. True/False. Refrigeration will destroy parasites and should never be used for temporary storage of a specimen.
    • False.
    • A sample can be refrigerated if it can't be sent to the lab immediately (up to 48 hrs). Trophozoite motility will be lost but organisms will be present for identification.
  71. A patient complains of GI upset. You order the following: Barium enema, prescription for pepto-bismol, cod liver oil and on O&P exam. Does the sequence of this series of items matter?
    • Obtain O&P sample first.
    • Administration of oil, bismuth, barium, and antibiotics will make it impossible to identify parasites if present.
  72. How many microscopic fields should be examines when searching for parasites microscopically?
    • Lab doesn't count fields.
    • Entire 22mm square cover-slip with overlapping fields are examined.
  73. Why is it important to note your suspicions on the lab request when you order an O&P?
    Lab will be alerted with your suspicions and may have to use special techniques or precautions to process your request.
  74. What simple steps can everyone take to avoid infectious diseases, especially parasitic infections?
    • Wash hands
    • Wash food
    • Cook food well
    • Drink clean water
    • Avoid insects (vectors)
    • Dispose of human excrement properly
  75. How many different types of specimen can you think of to submit for examination for parasites? Which one is the most common?
    • Stool is most common.
    • Blood/serum (serology)
    • Vaginal swabs
    • Sputum
    • Urine
    • CSF
  76. What do you think would be the specimen of choice for an intestinal lumen-dwelling parasite?
    Stool (O&P)
  77. Describe the collection technique for a stool sample.
    • Provide feces only
    • No tissue, water, or urine
    • No breakable jars or glass
    • Portions are stirred into vials of PVA (polyvinyl alcohol preservative) and 10% formalin.
  78. What does a lab report annotating "NPF" or "NPS" mean? Is this a negative result?
    • No parasites found/ no parasites seen.
    • Not the same as negative, the second sample may yield a lot since some parasites are passed in "showers".
  79. What is the best source of information for serological testing available to you at your current location?
    Call the lab officer and ask.
  80. Why is it important to wash your hands?
    • Clinicians are in a position to spread microbes from patient to patient easily.
    • CDC shows there are 90,000 recorded annually that could be prevented by handwashing.
    • Don't add to that number!
  81. Name ways a parasite may cause damage to the human host.
    • Tissue damage
    • Blood loss
    • Vigorous immune response (damages host tissue)
    • Secondary bacterial infections
    • Discomfort
    • Death
  82. How does a human host acquire a parasitic infection?
    • Ingestion
    • Injection
    • Direct penetration
  83. Is it appropriate to freeze a stool specimen to preserve it until it can be examined?
    • No.
    • Can be refrigerated if delivery to the lab is delayed, but do not freeze.
  84. Which part of the stool specimen is of most interest to the lab?
    • Really ugly bits.
    • Nice, smooth, peanut butter consistency material may not yield much.
    • Bloody, mucoid, nasty looking stool is where parasites are found.
  85. What can be done to prevent the spread of parasitic disease?
    • Wash hands
    • Wash food
    • Cook food
    • Drink clean water
    • Avoid insects (vectors)
    • Properly dispose of human excrement
    • (Not easily accomplished when deployed).
  86. Are our troops currently deployed to any areas that might have parasitic diseases? Where? What diseases? Could you diagnose these? What test and drugs might be available?
    • Afghanistan and Iraq have several parasitic disease problems.
    • Try using CDC yellow book and loos up info about these areas to see what can be learned.
  87. Definition: any parasite which lives in the internal organs of an animal, as in the tapeworms, Trichnia, etc; opposed to ectoparasite.
  88. What is the term for schistosoma that is used most often in Spanish-speaking countries?
  89. Definition: the essential elements of an organ.
  90. Definition: a combining form meaning divided or denoting relationship to division. Splitters.
    Schiz, schizo
  91. Defintion: a form a asexual reproduction characteristic of certain sarcodines and sporozoa in which daughter cells are produced by multiple fission of the nucleus of the parasite followed by segmentation of cytoplasm to form separate masses around each smaller nucleus.
  92. Definition: the multinucleate stage or form in the development of certain sarcodines and sporozoa during schizogony.
  93. Definition: the attachment of a tapeworm, or the head.
  94. Definition: the elongate, nucleated, motile infective stage resulting from sporogony in gregarine and coccidian protozoa. In malaria, this form of Plasmodium spp. are liberated from the oocysts in the mosquito, accumulate in the vector's salivary glands, and are transferred to the definitive host when bitten.
  95. Definition: a method of animal inoculation using laboratory-bred bugs and animals in the diagnosis of certain parasitic infections when it is not possible to deomstrate the infecting organism in blood films. Originally used in diagnosing Trypanosoma cruzi (Chaga's Disease).
  96. Name the genus and species of the trematode commonly known as the Chinese Liver Fluke.
    Clonorchis sinensis
  97. Name the genus and species of the trematode known as the Sheep Liver Fluke.
    Fasciola hepatica
  98. Name the genus and species of the trematode known as the Lung Fluke.
    Paragonimus westernami
  99. This trematode may encyst in the lungs and produce eggs that can be detected in the sputum and stool.
    Paragonimus westermani
  100. Infections with this trematode are commonly acquired by ingestion of raw or poorly cooked crabs or crayfish.
    Paragonimus westermani
  101. This group of trematodes are very difficult to distinguish in the egg stage. You might receive a lab report naming them all.
    • Clonorchis sinensis: liver
    • Opisthorchis felineus: liver
    • Opisthorchis viverini: liver
    • Metagonimus yokogawai: intestine
    • Heterophyes heterophyes: intestine
  102. These two trematodes are known as blood flukes, their eggs are found in stool specimens.
    • Schistosoma mansoni
    • Schistosoma japonicum
    • Their eggs are laid in the blood vessels near the intestinal wall, and eventually work their way into the stool.
  103. This trematode is an exception to the "stool for O&P rule". You want to examine urine to detect this infection.
    Schistosoma hematobium
  104. Lack of this intermediate host precludes the establishment of Schistosome infection in the continental U.S.
    Species of snail.
  105. Infection with this trematode is acquired by the direct penetration of human skin by the cercariae.
    • Schistosoma mansoni
    • Schistosoma hematobium
    • Schistosoma japonicum
  106. Ingestioin of raw or poorly cooked infected fish can lead to infection with this trematode.
    Clonorchis sinensis
  107. Ingestion of water plants containing metacercariae can lead to infection with this trematode.
    Fasciola hepatica
  108. This trematode disease is also called bilharzia.
  109. Schistosomes are called blood flukes. The specimens used to diagnose schistosomes are stool and urine. Why don't we collect blood since the worms live in blood vessels?
    Female worms deposit eggs in the portal vessels and perivesical systems. These sharply barbed eggs are pushed toward the lumen of the intestine (or bladder), break through and eggs spill into urine and fecal flow.
  110. Name the schistosome(s) recovered from feces.
    • Schistosoma mansoni
    • Schistosoma japonicum
  111. Name schistosome(s) recovered from urine.
    Schistosoma hematobium
  112. Which schistosome egg has a large lateral spine?
    Schistosoma mansoni
  113. Which schistosome egg has a terminal spine?
    Schistosoma hematobium
  114. Which schistosome egg has a small, inconspicuous spine on the lateral surface?
    Schistosoma japonicum
  115. These members of platyhelminthes (flatworms) penetrate snails and multiply in sporocysts to increase their numbers.
  116. Penetration of human skin by cercariae which are species specific for another host (ei waterfowl) results in a condition known as...?
    Swimmer's itch
  117. True/False. The greatest pathology produced by Schistosoma mansoni is caused by adults consuming the blood of the host.
    • False.
    • Adults produce many many eggs which are highly antigenic. The human body responds to this antigen and damages tissue. Eggs cut tissue and can lead to secondary bacterial infection. Eggs are the source of pathology.
  118. Gross, visible blood in the urine would cause you to add this parasite to your differential diagnosis.
    Schistosoma hematobium
  119. This trematode is commonly known as the lung fluke.
    Paragonimus westermani
  120. How may one become infected with Paragonimus westermani?
    Ingestion of raw or poorly cooked infected crabs or crayfish.
  121. True/False. Lung flukes migrate in the human by flowing along with the bloodstream to the lungs where they settle out and encyst.
    • False.
    • Immature flukes penetrate into the abdominal cavity, migrate to the lungs by penetrating the diaphragm and mature to adults. They can also migrate to other tissue (brain, muscle, liver, skin, testes) but eggs can't pass to the external environment from these sites so the eggs can go undetected.
  122. True/False. Trematodes (flukes) are exclusively parasites of internal organs.
    • False.
    • Fasciolopsis buski, Heterophyes and Metagonimus are intestinal flukes. If you subscribe to the description of the intestine being a tube within a tube, then these flukes aren't inhabiting internal organs.
  123. Name a parasite acquired by eating waterplants contaminated with metacercariae.
    • Fasciolopsis buski
    • Fasciola hepatica
  124. True/False. Fasciolopsis buski sucks blood from intestinal tissue and causes severe anemia.
    • False.
    • Fasciolopsis buski attaches to epithelium, and feeds on intestinal tissue. Light infections can cause intermittent diarrhea and hemorrhage. Patients complain of abdominal pain (simulates peptic ulcers).
  125. What is the causative agent of sheep liver fluke infection?
    Fasciola hepatica
  126. What is the genus and species of the Oriental Lung Fluke?
    Paragonimus westermani
  127. Name the trematode egg that is characterized as having "wide shoulders".
    Paragonimus westermani
  128. What is the agent responsible for bilharzia?
    Schistosoma mansoni
  129. Which trematode egg has a prominent lateral spine?
    Schistosoma mansoni
  130. Which trematode egg has a terminal spine?
    Schistosoma hematobium
  131. Which trematode egg has an inconspicuous spine?
    Schistosoma japonicum
  132. What is the specimen of choice for Schistosoma hematobium?
  133. What is the specimen of choice for Schistosoma mansoni?
    Stool for O&P
  134. How are schistosomes acquired?
    Direct penetration of larvae.
  135. Are schistosomes monoecious or dioecious?
    Dioecious (male and female)
  136. Blood in urine would be associated with which schistosome?
    Schistosoma hematobium
  137. Pipe stem fibrosis may occur with which schistosome?
    Schistosoma mansoni
  138. Name trematodes found in the blood stream.
    • Schistosoma mansoni
    • Schistosoma japonicum
    • Schistosoma hematobium
    • Eggs are found elsewhere, the adults are in the blood hence the term "blood flukes".
  139. Name a trematode found in the liver.
    Fasciola hepatica
  140. Name a trematode found in the lung.
    Paragonimus westermani