Micro 8.11 Parasitology Flashcards
- The incorrect match between organism and the appropriate diagnostic procedure is:
A. Onchocerca volvulus—examination of skin snips
B. Cryptosporidium spp.—modified acid-fast stain
C. Enterobius vermicularis—routine ova and parasite examination
D. Schistosoma haematobium—examination of urine sediment
C. Enterobius vermicularis—routine ova and parasite examination
- In a patient with diarrhea, occasionally Entamoeba histolytica/E. dispar (four nucleated cysts, no chromatoidal bars) are identified as being present; however, these cells, which are misdiagnosed as protozoa, are really:
A. Macrophages
B. Polymorphonuclear leukocytes (PMNs)
C. Epithelial cells
D. Eosinophils
B. Polymorphonuclear leukocytes (PMNs)
- Charcot-Leyden crystals in stool may be associated with an immune response and are thought to be formed from the breakdown products of:
A. Neutrophils
B. Eosinophils
C. Monocytes
D. Lymphocytes
B. Eosinophils
- Parasitic organisms that may be transmitted sexually do not include:
A. Entamoeba gingivalis
B. Dientamoeba fragilis
C. Trichomonas vaginalis
D. Diphyllobothrium latum
D. Diphyllobothrium latum
- The incorrect match between the organism and one method of acquiring the infection is:
A. Trypanosoma brucei rhodesiense—bite of sand fleas
B. Giardia lamblia (G. intestinalis, G. duodenalis)—ingestion of water contaminated with cysts
C. Hookworm—skin penetration of larvae from soil
D. Toxoplasma gondii—ingestion of infected raw or rare meats
A. Trypanosoma brucei rhodesiense—bite of sand fleas
- Upon examination of stool material for Cystoisospora belli, one would expect to see:
A. Cysts containing sporozoites
B. Precysts containing chromatoidal bars
C. Oocysts that are modified acid-fast positive
D. Sporozoites that are hematoxylin positive
C. Oocysts that are modified acid-fast positive
- Which specimen is the least likely to provide recovery of Trichomonas vaginalis?
A. Urine
B. Urethral discharge
C. Vaginal discharge
D. Feces
D. Feces
- 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 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 (G. intestinalis, G. duodenalis)
D. Balantidium coli
C. Giardia lamblia (G. intestinalis, G. duodenalis)
- Gram staining of a sample from a gum lesion showed what appeared to be amoebae. A trichrome smear showed amoebae with a single nucleus and partially digested PMNs. The correct identification is:
A. Trichomonas tenax
B. Entamoeba histolytica/Entamoeba dispar
C. Entamoeba gingivalis
D. Entamoeba polecki
C. Entamoeba gingivalis
- An E. histolytica (true pathogen) trophozoite has the following characteristics:
A. Compact karyosome in the nucleus, ingested RBCs, and clear pseudopodia
B. Ingested RBCs, clear pseudopodia, and uneven chromatin on the nuclear membrane
C. Ingested RBCs, clear pseudopodia, and large glycogen vacuoles in cytoplasm
D. Large, blotlike karyosome, ingested white blood cells (WBCs), and granular pseudopods
A. Compact karyosome in the nucleus, ingested RBCs, and clear pseudopodia
- A 12-year-old girl is brought to the emergency room with meningitis and a history of swimming in a warm-water spring. Motile amoebae that measure 10 μm in size are seen in CSF and are most likely:
A. Iodamoeba bütschlii trophozoites
B. Endolimax nana trophozoites
C. Dientamoeba fragilis trophozoites
D. Naegleria fowleri trophozoites
D. Naegleria fowleri trophozoites
- 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
- Visceral larva migrans is associated with which of the following organisms and diagnostic method?
A. Toxocara—serology
B. Onchocerca—skin snips
C. Dracunculus—skin biopsy
D. Angiostrongylus—CSF examination
A. Toxocara—serology
- The following organisms are linked with specific, relevant information. The incorrect combination is:
A. Strongyloides stercoralis—internal autoinfection
B. Echinococcus granulosus—hydatid examination
C. Toxoplasma gondii—serology
D. Balantidium coli—common in the United States
D. Balantidium coli—common in the United States
- Examination of 24-hour unpreserved urine specimen is sometimes helpful in the recovery of:
A. Trichomonas vaginalis trophozoites
B. Schistosoma haematobium eggs
C. Enterobius vermicularis eggs
D. Strongyloides stercoralis larvae
B. Schistosoma haematobium eggs
- The examination of sputum may be necessary to diagnose infection with:
A. Paragonimus westermani
B. Trichinella spiralis
C. Wuchereria bancrofti
D. Fasciola hepatica
A. Paragonimus westermani
- Two helminth eggs that may resemble one another are:
A. Diphyllobothrium latum and Paragonimus westermani
B. Opisthorchis sinensis and Fasciolopsis buski
C. Taenia saginata and Hymenolepis nana
D. Ascaris lumbricoides and Trichostrongylus
A. Diphyllobothrium latum and Paragonimus westermani
- Eating poorly cooked infected 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
- 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
- The adult tapeworm of Echinococcus granulosus is found in the intestine of:
A. Dogs
B. Sheep
C. Humans
D. Cattle
A. Dogs
- 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 the above
C. Either the definitive or the intermediate host
- Humans acquire infections with Diphyllobothrium latum adult worms by:
A. Ingestion of freshwater crabs
B. Skin penetration of cercariae
C. Ingestion of water chestnuts
D. Ingestion of raw freshwater fish
D. Ingestion of raw freshwater fish
- Humans can serve as both the intermediate and definitive host in infections caused by:
A. Enterobius vermicularis
B. Hymenolepis nana
C. Schistosoma japonicum
D. Ascaris lumbricoides
B. Hymenolepis nana
- Babesia is an organism that 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. Microsporidian spores
A. Plasmodium falciparum rings
- Organisms (and infections) that under normal conditions cannot be transmitted in the laboratory are:
A. Cryptosporidium—cryptosporidiosis
B. Taenia solium—cysticercosis
C. Ascaris lumbricoides—ascariasis
D. Enterobius vermicularis—pinworm infections
C. Ascaris lumbricoides—ascariasis
- Toxoplasma gondii is characterized by:
A. Possible congenital infection and ingestion of oocysts
B. Cosmopolitan distribution and possible difficulties with interpretation of serological results
C. None of the above
D. Both A and B
D. Both A and B
- Oocysts of Cryptosporidium spp. can be detected in stool specimens by using:
A. Modified acid-fast stain
B. Gram stain
C. Methenamine silver stain
D. Trichrome stain
A. Modified acid-fast stain
- Which microfilariae are usually not found circulating in peripheral blood?
A. Brugia malayi
B. Wuchereria bancrofti
C. Onchocerca volvulus
D. Loa loa
C. Onchocerca volvulus
- Massive hemolysis, blackwater fever, and central nervous system involvement are most common with:
A. Plasmodium vivax
B. Plasmodium falciparum
C. Plasmodium ovale
D. Plasmodium malariae
B. Plasmodium falciparum
- Organisms that should be considered in a nursery school outbreak of diarrhea include:
A. Endolimax nana, Giardia lamblia (G. intestinalis, G. duodenalis), and Entamoeba coli
B. Giardia lamblia (G. intestinalis, G. duodenalis), Dientamoeba fragilis, and Cryptosporidium parvum
C. Cryptosporidium spp., Trichomonas vaginalis, and Entamoeba coli
D. Trichomonas hominis, Dientamoeba fragilis, and Endolimax nana
B. Giardia lamblia (G. intestinalis, G. duodenalis), Dientamoeba fragilis, and Cryptosporidium parvum
- The incorrect match between disease and symptoms is:
A. Paragonimiasis—hemoptysis
B. Cryptosporidiosis—watery diarrhea
C. Toxoplasmosis in compromised host—central nervous system symptoms
D. Enterobiasis—dysentery
D. Enterobiasis—dysentery