L1 PARA Flashcards
The intestinal nematode considered capable of vertical transmission and the potential cause for congenital infections is:
A. Ascaris lumbricoides
B. Enterobius vermicularis
C. Trichuris trichiura
D. Ancylostoma duodenale
D. Ancylostoma duodenale
AUTOFLUORESCENCE requires no stain and is recommended for the identification of:
A. Entamoeba histolytica cysts
B. Toxoplasma gondii tachyzoites
C. Dientamoeba fragilis trophozoites
D. Cyclospora cayetanensis oocysts
D. Cyclospora cayetanensis oocysts
This diagnostic stage of Strongyloides stercoralis is best seen in stool using fecal concentration techniques:
A. Eggs
B. Rhabditiform larvae
C. Filariform larvae
D. Adult worms
B. Rhabditiform larvae
The causative agent of plague is most often transmitted to humans by:
A. Fleas
B. Mosquitos
C. Dog bites
D. Inhalation
A. Fleas
MODIFIED TRICHROME STAIN FOR MICROSPORIDIA
Specimen:
1.Fresh
2.Refrigerated
3.Fixed with ethanol
4.Fixed with formalin
A. 1 and 3
B. 1 and 4
C. 2 and 3
D. 2 and 4
B. 1 and 4
The rhabditiform larva of the hookworm has a:
A. Long buccal cavity, prominent genital primordium
B. Long buccal cavity, small genital primordium
C. Short buccal cavity, prominent genital primordium
D. Short buccal cavity, small genital primordium
B. Long buccal cavity, small genital primordium
The rhabditiform larva of the threadworm has a:
A. Long buccal cavity, prominent genital primordium
B. Long buccal cavity, small genital primordium
C. Short buccal cavity, prominent genital primordium
D. Short buccal cavity, small genital primordium
C. Short buccal cavity, prominent genital primordium
Infective stage is the SHEATHED FILARIFORM LARVA:
A. Strongyloides stercoralis
B. Ancylostoma duodenale, Necator americanus
C. Ascaris lumbricoides
D. Enterobius vermicularis
B. Ancylostoma duodenale, Necator americanus
Infective stage is the UNSHEATHED FILARIFORM LARVA:
A. Strongyloides stercoralis
B. Ancylostoma duodenale, Necator americanus
C. Ascaris lumbricoides
D. Enterobius vermicularis
A. Strongyloides stercoralis
Similar to hookworm eggs:
A. Ascaris
B. Trichuris
C. Trichostrongylus
D. Enterobius
C. Trichostrongylus
The two species of flies responsible for the transmission are Glossina palpalis and Glossina tachinoides:
A. Leishmania donovani
B. Leishmania tropica
C. Trypanosoma brucei gambiense
D. Trypanosoma brucei rhodesiense
C. Trypanosoma brucei gambiense
The two primary species of fly vectors responsible for transmitting are Glossina morsitans and Glossina pallidipes:
A. Leishmania donovani
B. Leishmania tropica
C. Trypanosoma brucei gambiense
D. Trypanosoma brucei rhodesiense
D. Trypanosoma brucei rhodesiense
Adult location of S. japonicum:
A. Veins surrounding the bladder
B. Venules of the small intestines
C. Venules of large intestines
D. None of these
B. Venules of the small intestines
Adult location of S. mansoni:
A. Veins surrounding the bladder
B. Venules of the small intestines
C. Venules of large intestines
D. None of these
C. Venules of large intestines
Adult location of S. haematobium:
A. Veins surrounding the bladder
B. Venules of the small intestines
C. Venules of large intestines
D. None of these
A. Veins surrounding the bladder
It resembles egg of S. haematobium, but acid-fast positive:
A. Schistosoma japonicum
B. Schistosoma mansoni
C. Schistosoma intercalatum
D. Schistosoma mekongi
C. Schistosoma intercalatum
Proglottids with 15 to 20 lateral branches in dichotomous or tree-like arrangement:
A. D. latum
B. T. saginata
C. T. solium
D. D. caninum
B. T. saginata
Proglottids with 7 to 13 lateral branches in a dendritic or finger-like arrangement:
A. D. latum
B. T. saginata
C. T. solium
D. D. caninum
C. T. solium
Early ring stages of the fifth human malaria, Plasmodium knowlesi, resemble those of:
A. Plasmodium malariae
B. Plasmodium ovale
C. Plasmodium falciparum
D. Plasmodium vivax
C. Plasmodium falciparum
Older developing stages (trophs, schizonts) of the fifth human malaria, P. knowlesi, resemble those of:
A. Plasmodium malariae
B. Plasmodium ovale
C. Plasmodium falciparum
D. Plasmodium vivax
A. Plasmodium malariae
Plasmodium vivax and Plasmodium ovale are similar because they:
A. Exhibit Schüffner’s dots and have a true relapse in the life cycle
B. Have no malarial pigment and multiple rings
C. Commonly have appliqué forms in the red cells
D. Have true stippling, do not have a relapse stage, and infect old red cells
E. Have a 72-hour periodicity cycle in the RBCs
A. Exhibit Schüffner’s dots and have a true relapse in the life cycle
Which species of malaria parasite usually has ameboid trophozoites and produces small reddish dots in the red blood cell cytoplasm?
A. Plasmodium knowlesi
B. Plasmodium falciparum
C. Plasmodium malariae
D. Plasmodium vivax
D. Plasmodium vivax
BAND TROPHOZOITES
Trophozoite tends to form “BANDS” across the cell:
A. P. vivax
B. P. malariae
C. P. falciparum
D. P. ovale
B. P. malariae
Synchronized rupture of RBCs every 72 hours:
A. P. falciparum
B. P. vivax
C. P. ovale
D. P. malariae
D. P. malariae
ROSETTE UTERUS
Gravid proglottids characteristically contain a centrally located uterine structure that frequently assumes a rosette formation.
A. D. caninum
B. D. latum
C. T. saginata
D. T. solium
B. D. latum
A method to culture Acanthamoeba species from corneal ulcer scrapings is to inoculate:
A. McCoy cells
B. Novy, MacNeal and Nicolle (NNN) medium
C. An agar plate overlaid with Escherichia coli
D. Regan-Lowe medium
C. An agar plate overlaid with Escherichia coli
A patient is suspected of having amoebic dysentery. Upon microscopic examination of a fresh fecal specimen for ova and parasites, the data shown are obtained:
A trophozoite of 25 μm
Progressive, unidirectional crawl
Evenly distributed peripheral chromatin
Finely granular cytoplasm
This information indicates:
A. Entamoeba coli
B. Entamoeba histolytica
C. Endolimax nana
D. Iodamoeba butschlii
B. Entamoeba histolytica
Charcot–Leyden crystals in stool may be associated with an immune response and are thought to be formed from the breakdown products of:
A. Neutrophil
B. Eosinophils
C. Monocytes
D. Lymphocytes
B. Eosinophils
Which of the following is the best technique to identify Dientamoeba fragilis in stool?
A. Formalin concentrate
B. Trichrome-stained smear
C. Modified acid-fast–stained smear
D. Giemsa’s stain
B. Trichrome-stained smear
One of the following protozoan organisms has been implicated in waterborne and foodborne outbreaks within the United States. The suspect organism is:
A. Pentatrichomonas hominis
B. Dientamoeba fragilis
C. Giardia lamblia
D. Balantidium coli
C. Giardia lamblia
Babesia has been implicated in disease from both splenectomized and nonsplenectomized patients. Morphologically, the parasites resemble:
A. Plasmodium falciparum rings
B. Leishmania donovani amastigotes
C. Trypanosoma cruzi trypomastigotes
D. Microsporidial spores
A. Plasmodium falciparum rings
Oocysts of Cryptosporidium spp. can be detected in stool specimens using:
A. Modified Ziehl–Neelsen acid-fast stain
B. Gram stain
C. Methenamine silver stain
D. Trichrome stain
A. Modified Ziehl–Neelsen acid-fast stain
Organisms that should be considered in a waterborne outbreak of diarrheal disease include:
A. Giardia lamblia and Cryptosporidium spp.
B. Endolimax nana and Entamoeba histolytica
C. Blastocystis hominis and Trichomonas vaginalis
D. Toxoplasma gondii and Schistosoma mansoni
A. Giardia lamblia and Cryptosporidium spp.
Eye infections with Acanthamoeba spp. have most commonly been traced to:
A. Use of soft contact lenses
B. Use of hard contact lenses
C. Use of contaminated lens care solutions
D. Failure to remove lenses while swimming
C. Use of contaminated lens care solutions
When staining Cystoisospora belli oocysts with modified acid-fast stains, the important difference between these methods and the acid-fast stains used for acid-fast bacilli (AFB) is:
A. The staining time is much longer with regular AFB acid-fast stains
B. The decolorizer is weaker than acid alcohol used for AFB decolorizing
C. A counterstain must be used for the modified methods
D. The stain is more concentrated when staining for AFB
B. The decolorizer is weaker than acid alcohol used for AFB decolorizing
There are few procedures considered STAT in parasitology. The most obvious situation would be:
A. Ova and parasite examination for giardiasis
B. Baermann’s concentration for strongyloidiasis
C. Blood films for malaria
D. Culture of amoebic keratitis
C. Blood films for malaria
Autofluorescence requires no stain and is recommended for the identification of:
A. Entamoeba histolytica cysts
B. Toxoplasma gondii tachyzoites
C. Dientamoeba fragilis trophozoites
D. Cyclospora cayetanensis oocysts
D. Cyclospora cayetanensis oocysts
The definitive host for Plasmodium is a:
A. Flea
B. Human
C. Mosquito
D. Fish
C. Mosquito
The intermediate host for Plasmodium is a:
A. Flea
B. Human
C. Mosquito
D. Fish
B. Human
Xenodiagnosis is used for which parasite?
A. Schistosoma mansoni
B. Trypanosoma cruzi
C. Loa loa
D. Wuchereria bancrofti
B. Trypanosoma cruzi
This organism is associated with PRIMARY AMOEBIC MENINGOENCEPHALITIS (PAM):
A. Naegleria fowleri
B. Acanthamoeba sp.
C. Entamoeba histolytica
D. Giardia lamblia
A. Naegleria fowleri
This organism is associated with GRANULOMATOUS AMEBIC ENCEPHALITIS (GAE):
A. Entamoeba histolytica
B. Dientamoeba fragilis
C. Naegleria fowleri
D. Acanthamoeba sp.
D. Acanthamoeba sp.
pam negra
gae sa kanto
In which of the following sets of nematodes can each organism cause a pneumonia-like syndrome in a person exposed to heavy infection with any of the three parasites?
A. Ascaris lumbricoides, Trichuris trichiura, or Onchocerca volvulus
B. Enterobius vermicularis, Dracunculus medinensis, or Trichuris trichiura
C. Strongyloides stercoralis, Wuchereria bancrofti, or Angiostrongylus costaricensis
D. Necator americanus, Ascaris lumbricoides, or Strongyloides stercoralis
D. Necator americanus, Ascaris lumbricoides, or Strongyloides stercoralis
A patient presents with vague abdominal pains and a microcytic hypochromic anemia. A possible causative parasite is:
A. Enterobius vermicularis
B. Ancylostoma duodenale
C. Brugia malayi
D. Trichinella spiralis
B. Ancylostoma duodenale
A child who plays in dirt contaminated with human and pet feces is susceptible to which of the following set of parasites?
A. Ascaris lumbricoides, Trichuris trichiura, Trichinella spiralis, Wuchereria bancrofti
B. Loa loa, Capillaria philippinensis, Enterobius vermicularis, Trichinella spiralis
C. Strongyloides stercoralis, Toxocara canis, Ascaris lumbricoides, Necator americanus
D. Ancylostoma braziliense, Trichuris trichiura, Trichinella spiralis, Necator americanus
C. Strongyloides stercoralis, Toxocara canis, Ascaris lumbricoides, Necator americanus
Adult location of S. japonicum:
A. Veins surrounding the bladder
B. Venules of the small intestines
C. Venules of large intestines
D. None of these
B. Venules of the small intestines
Adult location of S. mansoni:
A. Veins surrounding the bladder
B. Venules of the small intestines
C. Venules of large intestines
D. None of these
C. Venules of large intestines
Adult location of S. haematobium:
A. Veins surrounding the bladder
B. Venules of the small intestines
C. Venules of large intestines
D. None of these
A. Veins surrounding the bladder
The first intermediate host of Diphyllobothrium latum is:
A. Copepod
B. Snail
C. Fish
D. Crab
A. Copepod
What is the infective stage of the broad tapeworm to humans?
A. Plerocercoid
B. Coracidium
C. Hydatid cyst
D. Cysticercus
A. Plerocercoid
Which species of malaria parasite usually has ameboid trophozoites and produces small reddish dots in the red blood cell cytoplasm?
A. Plasmodium knowlesi
B. Plasmodium falciparum
C. Plasmodium malariae
D. Plasmodium vivax
D. Plasmodium vivax
Decontamination of drinking water, fruits, and vegetables before consumption is necessary in countries without well-developed public sanitation. Which of the following diseases would probably be LEAST affected by that kind of precaution?
A. Amebiasis
B. Ascariasis
C. Filariasis
D. Giardiasis
C. Filariasis
Top layer in the formalin ether (or ethyl acetate) concentration technique:
A. Debris/fat
B. Ether or ethyl acetate
C. Formalin
D. Sediment
B. Ether or ethyl acetate
Top to bottom Layers obtained in FECT:
A. Debris/fats, ether, formalin, sediment
B. Ether, debris/fats, formalin, sediment
C. Ether, formalin, debris/fats, sediment
D. Formalin, ether, debris/fats, sediment
B. Ether, debris/fats, formalin, sediment
Which of the following is the most important feature in differentiating cysts of Entamoeba histolytica from E. dispar?
A. Number of nuclei
B. Size of the cyst
C. Shape of the karyosome
D. Distinguishing surface antigens by immunologic assays
D. Distinguishing surface antigens by immunologic assays
Definitive host and the reservoir for W. bancrofti:
A. Anopheles
B. Aedes
C. Culex fatigans
D. Human
D. Human
Sheathed microfilaria, nuclei continuous up to the tip of the tail:
A. B. malayi
B. L.loa
C. O. volvulus
D. W. bancrofti
B. L.loa
Sheathed microfilaria, tail with 2 separate nuclei:
A. W. bancrofti
B. B. malayi
C. L. loa
D. O. volvulus
B. B. malayi
The organism is transmitted through a bite of the tabinid fly or deer fly of the genus Chrysops.
A. B. malayi
B. L. loa
C. O. volvulus
D. W. bancrofti
B. L. loa
The parasite is transmitted by the black fly, Simulium spp.
A. B. malayi
B. L. loa
C. O. volvulus
D. W. bancrofti
C. O. volvulus
How many stool samples should be collected when following the typical O&P collection protocol?
A. 1
B. 2
C. 3
D. 4
C. 3
Which of the following parasitic stages is NOT usually detected after using a concentration technique?
A. Protozoan cysts
B. Protozoan trophozoites
C. Helminth eggs
D. Helminth larvae
B. Protozoan trophozoites
The specimen of choice for the recovery of N. fowleri is which of the following?
A. Sputum
B. Stool
C. Cerebrospinal fluid
D. Urine
C. Cerebrospinal fluid
To prevent infection with Acanthamoeba species, contact lens wearers should avoid which of the following?
A. Strenuous exercise
B. Foods with high carbohydrate content
C. Wearing clothing made of cotton
D. Using homemade nonsterile saline solutions
D. Using homemade nonsterile saline solutions
The permanent stain of choice for the recovery of Cryptosporidium parvum is:
A. Iron hematoxylin
B. Modifed acid-fast
C. Gram
D. Trichrome
B. Modifed acid-fast
Which of the following are appropriate Ascaris lumbricoides prevention and control strategies?
A. Proper water treatment
B. Appropriate food handling
C. Use of insect repellent
D. Proper sanitation practices
D. Proper sanitation practices
This diagnostic stage of Strongyloides stercoralis is best seen in stool using fecal concentration techniques:
A. Eggs
B. Rhabditiform larvae
C. Filariform larvae
D. Adult worms
B. Rhabditiform larvae
Diagnostic stage of S. stercoralis: rhabditiform larva;
infective stage: filariform larva
What type of periodicity does Loa loa exhibit?
A. Nocturnal
B. Subperiodic
C. Diurnal
D. None
C. Diurnal
Skin snips are the specimen of choice for diagnosis of infection with:
A. Loa loa
B. Onchocerca volvulus
C. Brugia malayi
D. Wuchereria bancrofti
B. Onchocerca volvulus
Which of the following is characteristic of an H. diminuta egg?
A. Spherical, with radial striations
B. Ellipsoid, with terminal polar plugs
C. Oval, with thin shell and polar filaments
D. Oval, with polar thickenings and no filaments
D. Oval, with polar thickenings and no filaments
A primary differential feature between an H. nana egg and H. diminuta egg is which of the following?
A. A flattened side for H. diminuta egg
B. A thick shell for H. nana egg
C. Polar filaments in H. nana egg
D. Radial striations in H. diminuta egg
C. Polar filaments in H. nana egg
A 2-year-old girl and her pet dog were diagnosed with D. caninum infection. This infection was acquired by which of the following?
A. Ingestion of the parasite’s egg
B. Penetration of soil larva
C. Ingestion of a flea
D. Consumption of poorly cooked beef
C. Ingestion of a flea
The primary pathology associated with a D. latum infection is which of the following?
A. Eosinophilic pneumonitis
B. Vitamin D deficiency
C. Vitamin B12 deficiency
D. Fat malabsorption
C. Vitamin B12 deficiency
The first intermediate host for all the trematodes is which of the following?
A. Fish
B. Snail
C. Shrimp
D. Water plant
B. Snail
The typical transmission route of Paragonimus to humans consists of which of the following?
A. Consumption of contaminated crayfish or crabs
B. Swimming in contaminated water
C. Hand-to-mouth contamination
D. Walking barefoot on contaminated sandy soil
A. Consumption of contaminated crayfish or crabs
The specimen of choice for the recovery of Schistosoma japonicum is which of the following?
A. Tissue biopsy
B. Urine
C. Sputum
D. Stool
D. Stool
A systemic hypersensitivity reaction caused by the presence of Schistosoma is called which of the following?
A. Bilharziasis
B. Katayama fever
C. Swamp fever
D. Schistosomiasis
B. Katayama fever
Katayama fever is a systemic hypersensitivity reaction to the schistosomulae migrating through tissue.
Rapid onset of fever, nausea, myalgia, malaise, fatigue, cough, diarrhea, and eosinophilia occur 1 to 2 months after exposure. Although rare in chronically exposed persons, it is common in people new to endemic areas, such as tourists and travelers.
The adults of this species of Schistosoma dwell in the veins surrounding the urinary bladder:
A. S. haematobium
B. S. mansoni
C. S. japonicum
D. All of the above
A. S. haematobium
Ixodes ticks (deer ticks) can be found throughout the United States. Those in the New England area may be responsible for transmitting which of the following diseases?
1. Malaria
2. Babesia
3. Trypanosomiasis
4. Lyme disease
A. 1, 2, and 3 are correct
B. 1 and 3 are correct
C. 2 and 4 are correct
D. Only 4 is correct
E. None are correct
C. 2 and 4 are correct
Which of the following genera contain the organisms responsible for the disease SCABIES caused by the itch mite?
A. Sarcoptes spp.
B. Pediculus spp.
C. Ornithodorus spp.
D. Dermatophagoides spp.
A. Sarcoptes spp.
The Oriental rat flea, Xenopsylla cheopis, can be involved in transmitting which of the following microorganisms?
A. Rickettsia typhi
B. Hymenolepis nana
C. Yersinia pestis
D. Plasmodium spp.
E. A and C are correct
E. A and C are correct
Symptoms and signs mimic those of TUBERCULOSIS, and should always be suspected in patients with tuberculosis who are non-responsive to treatment:
A. Ascaris lumbricoides
B. Necator americanus
C. Strongyloides stercoralis
D. Paragonimus westermani
D. Paragonimus westermani
Infection mimics acute viral enteritis, bacillary dysentery, bacterial or other food poisonings, acute intestinal amebiasis, or “traveler’s diarrhea” (toxigenic Escherichia coli).
A. Entamoeba histolytica
B. Giardia lamblia
C. Isospora belli
D. Cryptosporidum parvum
B. Giardia lamblia
Small protozoa that have been missed on wet mounts or concentration methods are often detected with:
A. India ink
B. Iodine
C. Giemsa stain
D. Trichrome stain
D. Trichrome stain
Small protozoa that have been missed on wet mounts or concentration methods are often detected with the trichrome stain.
Schistosomal infection occurs through skin penetration by infected ____ released from a freshwater snail containing the intermediate stages of the schistosome life cycle.
A. Miracidium
B. Redia
C. Cercaria
D. Metacercaria
C. Cercaria
First stage larva liberated from the trematode egg:
A. Cercaria
B. Metacercaria
C. Redia
D. Sporocyst
E. Miracidium
E. Miracidium
The only amoeba that ingests WBCs:
A. E. coli
B. E. histolytica
C. E. gingivalis
D. E. nana
C. E. gingivalis
Which of the following is a unique characteristic of E. gingivalis?
A. The trophozoites exhibit active motility via their pseudopods.
B. There is no known cyst form of this parasite.
C. The trophozoite has a single nucleus with characteristics that resemble those of E. histolytica.
D. E. gingivalis is the only ameba that may ingest white blood cells.
D. E. gingivalis is the only ameba that may ingest white blood cells.
Gravid proglottids resemble RICE GRAINS (dry) or CUCUMBER SEEDS (moist):
A. Diphyllobothrium latum
B. Dipylidium caninum
C. Hymenolepis nana
D. Taenia spp.
B. Dipylidium caninum
Thick-walled POLLEN GRAINS resemble the eggs of:
A. Ascaris lumbricoides
B. Dipylidium caninum
C. Hymenolepis nana
D. Taenia species
D. Taenia species
Proglottids with 15 to 20 lateral branches in dichotomous or tree-like arrangement:
A. D. latum
B. T. saginata
C. T. solium
D. D. caninum
B. T. saginata
Proglottids with 7 to 13 lateral branches in a dendritic or finger-like arrangement:
A. D. latum
B. T. saginata
C. T. solium
D. D. caninum
C. T. solium
It is more frequent in populations living in conditions of poverty or poor hygiene, in day care centers, and in persons living in institutional settings or prisons.
A. Diphyllobothrim latum
B. Hymenolepis nana
C. Taenia solium
D. Taenia saginata
B. Hymenolepis nana
It causes alveolar hydatid disease which is the most lethal of all helminthic diseases:
A. Taenia saginata
B. Taenia solium
C. Echinococcus granulosus
D. Echinococcus multilocularis
D. Echinococcus multilocularis
Intermediate host of Echinococcus multilocularis:
A. Dogs
B. Foxes
C. Coyotes
D. Rodents
D. Rodents
A stool specimen was collected at 8 pm from a patient. Following collection the specimen was not submitted to the laboratory until 11 pm. The laboratory technologist found larvae with a long buccal cavity and a small, reduced genital primordium in the fecal sample. The larvae are most likely:
A. Ancylostoma duodenale
B. Strongyloides stercoralis
C. Trichuris trichiura
D. Unable to determine
A. Ancylostoma duodenale
MOT and IS Fasciolopsis buski
A. Ingestion of water plants, cercaria
B. Ingestion of water plants, metacercaria
C. Ingestion of fishes, cercaria
D. Ingestion of fishes, metacercaria
B. Ingestion of water plants, metacercaria
Fish carrying metacercariae may transmit:
A. Clonorchis sinensis
B. Fasciolopsis buski
C. Paragonimus westermani
D. Schistosoma haematobium
E. None of these
A. Clonorchis sinensis
Fluke(s) associated with CHOLECYSTITIS (inflammation of the gallbladder), and CHOLANGIOCARCINOMA (cancerous growth in bile duct epithelium):
A. F. buski
B. P. westermani
C. C. sinensis, O. viverrini
D. S. japonicum
C. C. sinensis, O. viverrini
Which of the following roundworms is capable of autoinfection, hyperinfection, and a heavy worm burden with characteristic larval migration required in the life cycle?
A. Ancylostoma duodenale
B. Enterobius vermicularis
C. Strongyloides stercoralis
D. Ascaris lumbricoides
C. Strongyloides stercoralis
The intestinal nematode considered capable of vertical transmission and the potential cause for congenital infections is:
A. Ascaris lumbricoides
B. Enterobius vermicularis
C. Trichuris trichiura
D. Ancylostoma duodenale
D. Ancylostoma duodenale
Infection may resemble acute appendicitis:
A. Parastrongylus costaricensis
B. Gnathostoma sp.
C. Toxocara cati
D. Parastrongylus caninum
A. Parastrongylus costaricensis
Which of the following species of Plasmodium produce hypnozoites that can remain dormant in the liver and cause a relapse months or years later?
A. P. falciparum
B. P. vivax
C. P. knowlesi
D. P. malariae
B. P. vivax
Quadrate scolex with 4 suckers; no rostellum or hooklets:
A. D. latum
B. T. saginata
C. T. solium
D. H. diminuta
B. T. saginata
Quadrate scolex with 4 suckers; has rostellum and hooklets:
A. D. latum
B. T. saginata
C. T. solium
D. H. diminuta
C. T. solium
Profuse watery diarrhea (“rice water stools”), leading to dramatic fluid loss, severe dehydration, and hypotension that frequently leads to death, is the hallmark of which toxin activity?
A. Cholera toxin
B. Enteric endotoxin
C. Shiga toxin
D. Toxin A
A. Cholera toxin
Which of the following is a disinfectant?
A. Benzalkonium chloride
B. Chlorhexidine gluconate
C. Household bleach
D. Hydrogen peroxide
C. Household bleach
Plasmodium falciparum:
A. The schizont contains 6 to 12 merozoites; generally abundant in hematin granules; may contain Ziemann stippling.
B. The most predominant species worldwide; 12 to 24 merozoites; may contain Schüffner dots or granules.
C. Infected erythrocytes may be enlarged and oval shaped; may contain Schüffner dots; 6 to 14 merozoites in the schizont.
D. Young trophozoites and gametocytes are generallythe only stage seen in peripheral blood; gametocytes appear as crescent- or sausage-shaped structures in erythrocytes; Maurer dots may be present.
D. Young trophozoites and gametocytes are generallythe only stage seen in peripheral blood; gametocytes appear as crescent- or sausage-shaped structures in erythrocytes; Maurer dots may be present.
Plasmodium malariae:
A. The schizont contains 6 to 12 merozoites; generally abundant in hematin granules; may contain Ziemann stippling.
B. The most predominant species worldwide; 12 to 24 merozoites; may contain Schüffner dots or granules.
C. Infected erythrocytes may be enlarged and oval shaped; may contain Schüffner dots; 6 to 14 merozoites in the schizont.
D. Young trophozoites and gametocytes are generallythe only stage seen in peripheral blood; gametocytes appear as crescent- or sausage-shaped structures in erythrocytes; Maurer dots may be present.
A. The schizont contains 6 to 12 merozoites; generally abundant in hematin granules; may contain Ziemann stippling.
Plasmodium vivax:
A. The schizont contains 6 to 12 merozoites; generally abundant in hematin granules; may contain Ziemann stippling.
B. The most predominant species worldwide; 12 to 24 merozoites; may contain Schüffner dots or granules.
C. Infected erythrocytes may be enlarged and oval shaped; may contain Schüffner dots; 6 to 14 merozoites in the schizont.
D. Young trophozoites and gametocytes are generallythe only stage seen in peripheral blood; gametocytes appear as crescent- or sausage-shaped structures in erythrocytes; Maurer dots may be present.
B. The most predominant species worldwide; 12 to 24 merozoites; may contain Schüffner dots or granules.
Most of the pathology associated with parasitic infections results from which of the following?
A. Symbiotic relationships with the host
B. Elaborate parasitic life cycles
C. Immune response to the offending organism
D. Innate defense mechanisms of the host
C. Immune response to the offending organism
The chronic nature of parasitic infections is caused by the host’s
A. Inability to eliminate the infective agent.
B. Type I hypersensitivity response to the infection.
C. Ability to form a granuloma around the parasite.
D. Tendency to form circulating immune complexes.
A. Inability to eliminate the infective agent.
Autofluorescence requires no stain and is recommended for the identification of:
A. Entamoeba histolytica cysts
B. Toxoplasma gondii tachyzoites
C. Dientamoeba fragilis trophozoites
D. Cyclospora cayetanensis oocysts
D. Cyclospora cayetanensis oocysts
Ingestion of which of the following EGGS will result in infection?
A. Strongyloides stercoralis
B. Schistosoma japonicum
C. Toxocara canis
D. Opisthorchis sinensis
C. Toxocara canis
Eye infections with Acanthamoeba spp. have most commonly been traced to:
A. Use of soft contact lenses
B. Use of hard contact lenses
C. Use of contaminated lens care solutions
D. Failure to remove lenses while swimming
C. Use of contaminated lens care solutions
Organisms that should be considered in a waterborne outbreak of diarrheal disease include:
A. Giardia lamblia and Cryptosporidium spp.
B. Endolimax nana and Entamoeba histolytica
C. Blastocystis hominis and Trichomonas vaginalis
D. Toxoplasma gondii and Schistosoma mansoni
A. Giardia lamblia and Cryptosporidium spp.
Oocysts of Cryptosporidium spp. can be detected in stool specimens using:
A. Modified Ziehl–Neelsen acid-fast stain
B. Gram stain
C. Methenamine silver stain
D. Trichrome stain
A. Modified Ziehl–Neelsen acid-fast stain
In infections with Taenia solium, humans can serve as the:
A. Definitive host
B. Intermediate host
C. Either the definitive or the intermediate host
D. None of these options
C. Either the definitive or the intermediate host
An operculated cestode egg that can be recovered from human feces is:
A. Clonorchis sinensis
B. Diphyllobothrium latum
C. Paragonimus westermani
D. Dipylidium caninum
B. Diphyllobothrium latum
Eating poorly cooked pork can lead to an infection with:
A. Taenia solium and Trichinella spiralis
B. Taenia saginata and Hymenolepis nana
C. Trichuris trichiura and Hymenolepis diminuta
D. Diphyllobothrium latum and Ascaris lumbricoides
A. Taenia solium and Trichinella spiralis
Characteristics of the rhabditiform (noninfective) larvae of Strongyloides stercoralis include a:
A. Short buccal capsule and large genital primordium
B. Long buccal capsule and pointed tail
C. Short buccal capsule and small genital primordium
D. Small genital primordium and notch in tail
A. Short buccal capsule and large genital primordium
An Entamoeba histolytica trophozoite has the following characteristics:
A. Central karyosome in the nucleus, ingestedRBCs, and clear pseudopodia
B. Ingested RBCs, clear pseudopodia, and unevenchromatin on the nuclear membrane
C. Ingested RBCs, clear pseudopodia, and largeglycogen vacuoles in cytoplasm
D. Large, blotlike karyosome, ingested white blood cells (WBCs), and granular pseudopods
A. Central karyosome in the nucleus, ingestedRBCs, and clear pseudopodia
Which of the following is the best technique to identify Dientamoeba fragilis in stool?
A. Formalin concentrate
B. Trichrome-stained smear
C. Modified acid-fast–stained smear
D. Giemsa’s stain
B. Trichrome-stained smear
INTESTINAL NEMATODES
SMALL INTESTINES (CASH)
Capillaria
Ascaris
Strongyloides
Hookworms
& T.spiralis adult
INTESTINAL NEMATODES
LARGE INTESTINES (ET)
Enterobius
Trichuris
Similar to hookworm eggs:
A. Ascaris
B. Trichuris
C. Trichostrongylus
D. Enterobius
C. Trichostrongylus
The BAERMANN TECHNIQUE yields a good concentration of the living larvae of:
A. Angiostrongylus cantonensis
B. Brugia malayi
C. Enterobius vermicularis
D. Strongyloides stercoralis
D. Strongyloides stercoralis
Roundworm that inhabits the small intestines and usually demonstrated as rhabditiform larva in stool:
A. A. lumbricoides
B. N. americanus
C. T. spiralis
D. S. stercoralis
D. S. stercoralis
The rhabditiform larva of the hookworm has a:
A. Long buccal cavity, prominent genital primordium
B. Long buccal cavity, small genital primordium
C. Short buccal cavity, prominent genital primordium
D. Short buccal cavity, small genital primordium
B. Long buccal cavity, small genital primordium
The rhabditiform larva of the threadworm has a:
A. Long buccal cavity, prominent genital primordium
B. Long buccal cavity, small genital primordium
C. Short buccal cavity, prominent genital primordium
D. Short buccal cavity, small genital primordium
C. Short buccal cavity, prominent genital primordium
Rhabditiform larva with hourglass-shaped esophagus and short buccal cavity:
A. Ascaris
B. Enterobius
C. Necator
D. Strongyloides
D. Strongyloides
Infective stage is the SHEATHED FILARIFORM LARVA:
A. Strongyloides stercoralis
B. Ancylostoma duodenale, Necator americanus
C. Ascaris lumbricoides
D. Enterobius vermicularis
B. Ancylostoma duodenale, Necator americanus
Infective stage is the UNSHEATHED FILARIFORM LARVA:
A. Strongyloides stercoralis
B. Ancylostoma duodenale, Necator americanus
C. Ascaris lumbricoides
D. Enterobius vermicularis
A. Strongyloides stercoralis
This diagnostic stage of Strongyloides stercoralis is best seen in stool using fecal concentration techniques:
A. Eggs
B. Rhabditiform larvae
C. Filariform larvae
D. Adult worms
B. Rhabditiform larvae
Necator americanus rhabditiform larvae can be differentiated from Strongyloides stercoralis rhabditiform larvae by:
A. Length of the notched tail
B. Length of the head region
C. Segmentation
D. Size of the genital primordium
D. Size of the genital primordium
Ova recovered from the stool are routinely used to diagnose infections caused by all of the following except?
A. Necator americanus
B. Ascaris lubricoides
C. Trichuris trichiura
D. Strongyloides stercoralis
D. Strongyloides stercoralis
More likely to contain trophozoites:
A. Liquid/diarrheic stool
B. Formed stool
C. Soft stool
D. None of these
A. Liquid/diarrheic stool
May contain trophozoites and cysts:
A. Liquid stool
B. Diarrheic stool
C. Formed stool
D. Soft stool
D. Soft stool
More likely to contain cysts (less likely to contain trophozoites)
A. Liquid stool
B. Diarrheic stool
C. Formed stool
D. Soft stool
C. Formed stool
Trophozoite forms of amoebae are found in what type of stool specimen?
A. Formed
B. Loose
C. Soft
D. Watery
D. Watery
The reduviid bug is the vector for transmitting which of the following parasites?
A. Leishmania donovani
B. Trypanosoma brucei gambiense
C. Trypanosoma brucei rhodesiense
D. Trypanosoma cruzi
E. Leishmania tropica
D. Trypanosoma cruzi
The infective stage of the Plasmodium parasite and the Babesia parasite for humans is the:
A. Merozoite
B. Trophozoite
C. Gametocyte
D. Sporozoite
D. Sporozoite
Ziemann’s dots, band form trophozoites, and 72-hour periodicity of paroxysms is indicative of infection with which Plasmodium species?
A. Plasmodium vivax
B. Plasmodium ovale
C. Plasmodium falciparum
D. Plasmodium malariae
D. Plasmodium malariae
These two nematodes are similar in that they are both suspected of being transport hosts of Dientamoeba fragilis.
A. Trichinella and Dracunculus
B. Necator and Trichuris
C. Strongyloides and Ancylostoma
D. Ascaris and Enterobius
D. Ascaris and Enterobius
Which of these parasites are contracted via skin penetration?
A. Enterobius, Necator, Dracunculus
B. Ascaris, Trichinella, Ancylostoma
C. Trichuris, Strongyloides, Enterobius
D. Ancylostoma, Strongyloides, Necator
D. Ancylostoma, Strongyloides, Necator
All of the following microfilariae lack a sheath except:
A. Mansonella ozzardi
B. Mansonella perstans
C. Onchocera volvulus
D. Brugia malayi
D. Brugia malayi
Which of the following filarial nematodes is transmitted by the Chrysops fly?
A. Onchocerca volvulus
B. Mansonella ozzardi
C. Loa loa
D. Brugia malayi
C. Loa loa
Which of the following filarial nematode infections is diagnosed by using skin snips rather than a peripheral blood smear?
A. Onchocerca volvulus
B. Loa loa
C. Mansonella perstans
D. Wuchereria bancrofti
A. Onchocerca volvulus
Consumption of the infective larval stage encysted on aquatic plants that have not been cooked results in infection with:
A. Clonorchis sinensis
B. Fasciola hepatica
C. Heterophyes heterophyes
D. Paragonimus westermani
B. Fasciola hepatica
The infective form of Schistosoma mansoni is which of the following?
A. Cercaria swimming in water
B. Metacercaria on or in fish
C. Metacercaria encysted on waterchestnuts or vegetables
D. Cercaria on water chestnuts, bambooshoots, or vegetables
A. Cercaria swimming in water
Pinworm disease may be diagnosed by which procedure?
A. Direct fecal smear
B. Cellophane tape test
C. Fecal concentration methods
D. Egg-count technique
B. Cellophane tape test
The definitive host for Plasmodium vivax is a:
A. Flea
B. Human
C. Mosquito
D. Fish
C. Mosquito
Xenodiagnosis is used for which parasite?
A. Schistosoma mansoni
B. Trypanosoma cruzi
C. Loa loa
D. Wuchereria bancrofti
B. Trypanosoma cruzi
Each of the following microfilaria has a sheath EXCEPT:
A. Brugia malayi
B. Loa loa
C. Mansonella ozzardi
D. Wuchereria bancrofti
C. Mansonella ozzardi
Visceral larval migrans is caused by:
A. Ascaris lumbricoides
B. Ancylostoma braziliense
C. Dirofilaria spp.
D. Toxocara canis
D. Toxocara canis
A type of tapeworm larva with a large bladder, producing daughter cysts, brood capsules, and numerous scolices is:
A. Cysticercus
B. Cysticercoid
C. Hydatid cyst
D. Plerocercoid
E. Procercoid
C. Hydatid cyst
In the Diphyllobothrium latum life cycle, the infective stage for humans is:
A. Cysticercus
B. Cysticercoid
C. Hydatid cyst
D. Procercoid
E. Plerocercoid
E. Plerocercoid
Which of the Platyhelminthes infects humans by skin penetration and has an association with bladder cancer?
A. Schistosoma mansoni
B. Schistosoma haematobium
C. Clonorchis sinensis
D. Schistosoma japonicum
B. Schistosoma haematobium
The two parasitic organisms most commonly associated with waterborne outbreaks of diarrhea include:
A. Blastocystis hominis and Cystoisospora belli
B. Entamoeba coli and Giardia lamblia
C. Entamoeba histolytica and Endolimax nana
D. Giardia lamblia and Cryptosporidium spp.
E. Pentatrichomonas hominis and Toxoplasma gondii
D. Giardia lamblia and Cryptosporidium spp.
Yersinia pestis is transmitted by:
A. Dermacentor spp.
B. Pediculus spp.
C. Sarcoptes scabiei
D. Xenopsylla spp.
D. Xenopsylla spp.
Which cestode produces an operculated egg?
A. Taenia saginata
B. Hymenolepis nana
C. Diphyllobothrium latum
D. Echinococcus granulosus
E. Taenia solium
C. Diphyllobothrium latum
Infection with Brugia malayi is best diagnosed by:
A. Zinc-sulfate flotation concentration
B. Cellophane tape test
C. Xenodiagnosis
D. Trichrome staining of a fecal smear
E. Knott concentration test
E. Knott concentration test
A small, operculated egg with a light bulb shape was found in the feces of a patient with liver abnormalities.
A. Fasciola hepatica
B. Paragonimus westermani
C. Fasciolopsis buski
D. Clonorchis sinensis
D. Clonorchis sinensis
In clinical cases of Wuchereria bancrofti, the most favorable time to find parasites in the blood is:
A. Early morning
B. Middle of the night
C. Late afternoon
D. Any time
B. Middle of the night
INDICATE MODE OF TRANSMISSION & INFECTIVE STAGE
All of the following except one infect humans by entrance of the infective stage through the skin. Which one has a different route of entrance?
A. Schistosoma japonicum
B. Strongyloides stercoralis
C. Ancylostoma duodenale
D. Necator americanus
E. Heterophyes heterophyes
E. Heterophyes heterophyes
MOT: ingestion of fish
IS: metacercaria
Babesia spp. is transmitted to humans by:
A. The bite of an infected tick
B. The bite of an infected fly (Chrysops spp.)
C. Ingestion of a cyst
D. The bite of an infected mosquito (Anopheles spp.)
A. The bite of an infected tick
Which of the following exhibits diurnal periodicity?
A. Wuchereria bancrofti
B. Brugia malayi
C. Loa loa
D. Onchocerca volvulus
C. Loa loa
Small protozoa that have been missed on wet mounts or concentration methods are often detected with:
A. India ink
B. Iodine
C. Giemsa stain
D. Trichrome stain
D. Trichrome stain
Sedimentation technique takes the advantage of the high specific gravity of protozoan cysts and helminth eggs compared to water. Their natural tendency to settle out in aqueous solutions can be accelerated by:
A. Filtration
B. Light centrifugation
C. Refrigeration
D. Freezing
B. Light centrifugation
Which of the following is the most important feature in differentiating cysts of Entamoeba histolytica from E. dispar?
A. Number of nuclei
B. Size of the cyst
C. Shape of the karyosome
D. Distinguishing surface antigens by immunologic assays
D. Distinguishing surface antigens by immunologic assays
In an examination of stained blood films, Babesia spp. are likely to resemble:
A. Leishmania donovani
B. Plasmodium falciparum
C. Toxoplasma gondii
D. Trypanosoma cruzi
B. Plasmodium falciparum
Oocysts, the infective stage of Toxoplasma gondii, is found in
A. Cat feces
B. Human feces
C. Undercooked pork
D. Undercooked beef
A. Cat feces
Which stage of Trichuris trichiura is infective for humans?
A. Proglottid
B. Filariform larva
C. Rhabditiform larva
D. Embryonated ovum
D. Embryonated ovum
Which of the following NEMATODE parasites is acquired from eating inadequately cooked, infected pork?
A. Strongyloides stercoralis
B. Taenia saginata
C. Taenia solium
D. Trichinella spiralis
D. Trichinella spiralis
Which preservation method is most suitable and the most widely used for subsequent fixed smear preparation?
A. Formalin-ethyl acetate
B. PVA
C. Trichrome
D. MIF
B. PVA
The only known human tapeworm with an operculum is:
A. Diphyllobothrium latum
B. Hymenolepis nana
C. Giardia lamblia
D. Schistosoma haematobium
A. Diphyllobothrium latum
Hermaphroditic, EXCEPT:
A. D. latum
B. F. buski
C. S. intercalatum
D. T. saginata
C. S. intercalatum
Nematode parasites that inhabit the large intestines:
Ascaris lumbricoides
Capillaria philippinensis
Threadworm, hookworm
Enterobius vermicularis
Trichuris trichiura
A. 1, 2 and 3
B. 1, 2 and 5
C. 4 and 5
D. 4 only
C. 4 and 5
KNOW THE INFECTIVE STAGE OF THESE PARASITES
Ingestion of which of the following EGGS will result in infection?
A. Strongyloides stercoralis
B. Schistosoma japonicum
C. Toxocara canis
D. Opisthorchis sinensis
C. Toxocara canis
Lice are most commonly transferred:
A. Inhalation
B. Blood transfusion
C. Directly from person to person
D. Infected clothing or other personal articles
C. Directly from person to person
“CRESCENT” or “SAUSAGE” shaped gametocytes; may appear in “SHOWERS” with black pigment near chromatin dot, which is often central:
A. Plasmodium falciparum
B. Plasmodium malariae
C. Plasmodium ovale
D. Plasmodium vivax
A. Plasmodium falciparum
The eggs contain a six-hooked oncosphere with the ABSENCE OF POLAR FILAMENTS in the space between the oncosphere and the eggshell:
A. Hymenolepis nana
B. Hymenolepis diminuta
C.Taenia saginata
D. Taenia solium
B. Hymenolepis diminuta