ROBERT HARR Flashcards
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
C. Epithelial cells
D. Eosinophils
Polymorphonuclear leukocytes
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
Eosinophils
The incorrect match between organism and the appropriate diagnostic procedure is:
A. Onchocerca volvulus—examination of skin snips
B. Cryptosporidium—modified acid-fast stain
C. Echinococcus granulosus—routine ova and parasite examination
D. Schistosoma haematobium—examination of urine sediment
Echinococcus granulosus—routine ova and parasite examination
Parasitic organisms that are most often transmitted sexually include:
A. Entamoeba gingivalis
B. Dientamoeba fragilis
C. Trichomonas vaginalis
D. Diphyllobothrium latum
Trichomonas vaginalis
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—ingestion of water contaminated with cysts
C. Hookworm—skin penetration of larvae from soil
D. Toxoplasma gondii—ingestion of raw or rare meats
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 variable
D. Sporozoites that are hematoxylin positive
Oocysts that are modified acid-fast variable
Which specimen is the least likely to provide
recovery of Trichomonas vaginalis?
A. Urine
B. Urethral discharge
C. Vaginal discharge
D. Feces
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’s stain
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
Giardia lamblia
A Gram stain 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/E. dispar
C. Entamoeba gingivalis
D. Entamoeba polecki
Entamoeba gingivalis
An Entamoeba histolytica trophozoite has the
following characteristics:
A. Central 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
Central karyosome in the nucleus, ingested
RBCs, and clear pseudopodia
A 12-year-old girl is brought to the emergency
department with meningitis and a history of
swimming in a warm-water spring. Motile
amoebae that measure 10 μ in size are seen in
the CSF and are most likely:
A. Iodamoeba bütschlii trophozoites
B. Endolimax nana trophozoites
C. Dientamoeba fragilis trophozoites
D. Naegleria fowleri trophozoites
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
Short buccal capsule and large genital
primordium
Visceral larva migrans is associated with which of the following organisms?
A. Toxocara—serology
B. Onchocerca—skin snips
C. Dracunculus—skin biopsy
D. Angiostrongylus—CSF examination
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—serology
D. Balantidium coli—common within the
United States
Balantidium coli—common within 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
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
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
Diphyllobothrium latum and Paragonimus
westermani
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
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
Diphyllobothrium latum
The adult tapeworm of Echinococcus granulosus is found in the intestine of:
A. Dogs
B. Sheep
C. Humans
D. Cattle
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 these options
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
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
Hymenolepis nana
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
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
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. Neither A nor B
D. Both A and B
Both A and B
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
Modified Ziehl–Neelsen acid-fast stain
Which microfilariae are usually not found
circulating in the peripheral blood?
A. Brugia malayi
B. Wuchereria bancrofti
C. Onchocerca volvulus
D. Loa loa
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
Plasmodium falciparum
Organisms that should be considered in a nursery school outbreak of diarrhea include:
A. Endolimax nana, Giardia lamblia, and
Entamoeba coli
B. Giardia lamblia, Dientamoeba fragilis, and
Cryptosporidium spp.
C. Cryptosporidium spp., Trichomonas vaginalis, and Entamoeba coli
D. Pentatrichomonas hominis, Dientamoeba fragilis, and Endolimax nana
Giardia lamblia, Dientamoeba fragilis, and
Cryptosporidium spp.
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
Enterobiasis—dysentery