Assessment Exam 2 Rationale Flashcards
The primary site of infection with Entameoba histolytica in humans is the
a. skin
b. duodenum
c. cecum and colon
d. liver
e. pericardium
c
The one species among the following that is associated with anemia is
a. Strongyloides stercoralis
b. Diphyllobothrium latum
c. Ancylostoma duodenale
d. Trichuris trichiura
e. all of the above
c - IDA
A skin biopsy taken from the lesion of an individual with mucocutaneous leishmaniasis is most likely to show
a. flagellated promastigotes in polymorphonuclear neutrophils
b. schizonts
c. amastigotes undergoing binary fission
d. eosinophilic granuloma formation
e. extensive tissue necrosis with only rare protozoan forms
c
Which statement is true concerning molecular-based paternity testing?
a. Paternity testing is typically performed using VNTR loci in the mother, child and alleged father
b. Single mismatch between an allele in the child (that must have come from the father of the child) and the alleged father is sufficient to exclude the alleged father
c. Match between the alleged father and the child at a rare allele carries less weight in paternity than does a match involving a higher frequency allele
d. Paternity index is calculated for the alleged father using all loci tested, even if one of the loci does not directly match the child.
d
1-2 mismatches allowed
A cestode that competes with its definitive host for dietary vitamin B12 is
a. Taenia saginata
b. Taenia solium
c. Diphyllobothrium latum
d. Hymenolepsis nana
e. Echinococcus granulosus
c
- Dibothriocephakus latus new name
Which organism is associated with blood in the urine and chronic urinary tract obstructions?
a. Schistosoma mansoni
b. Schistosoma haematobium
c. Schistosoma japonicum
d. Dracunculus medinensis
e. Paragonimus westermani
b
The developmental form of Leishmania transmitted to humans is the
a. trypomastigote
b. epimastigote
c. promastigote
d. amastigote
e. nomastigote
c
The infective stage
Ingestion of ova followed by larval migration to the lung characterizes the life cycle of
a. Strongyloides stercoralis
b. Ancylostoma duodenale
c. Wuchereria bancrofti
d. Ascaris lumbricoides
e. Necator americanus
d
The adult stage of the cestode life cycle does NOT take place in humans infected with
a. Taenia saginata
b. Taenia solium
c. Diphyllobothrium latum
d. Echinococcus granulosus
e. none of the above
d
Natural resistance to malaria caused by Plasmodium vivax has been demonstrated in populations who are
a. blood group antigen-positive
b. glycophorin A-positive
c. glucose-6-phosphate dehydrogenase-deficient
d. Duffy blood group antigen-negative
e. none of the above
d
Diagnosis can usually be established by examination of the stool in persons infected with
a. Ascaris lumbricoides
b. Strongyloides stercoralis
c. Taenia saginata
d. Schistosoma mansoni
e. all of the above
e
Coccidian protozoan restricted to production of intestinal disease and especially in acquired immunodeficiency syndrome patients
a. Toxoplasma gondii
b. Trypanosoma cruzi
c. Naegleria fowleri
d. Cryptosporidium
e. Plasmodium falciparum
d
Generally, humans are infected by eating raw beef.
a. Wuchereria bancrofti
b. Onchocerca volvulus
c. Taenia saginata
d. Hymenolepsis nana
c
Adult parasites are usually in the parenchyma of the human lung
a. Necator americanus
b. Taenia solium
c. Clonorchis sinensis
d. Paragonimus westermani
d
Entamoeba histolytica.
a. sporozoan intestinal disease in acquired immunodeficiency syndrome patients
b. interstitial pneumonitis in an immunosuppressed patient
c. fulminant hemorrhagic meningoencephalitis acquired during swimming
d. flatulent diarrhea after travel to Moscow
e. hepatic abscess
e
Over the past 3 months a 12-year-old boy heated home made pork sausage lightly and had it for dinner on many occasions. Now he has developed periorbital eosinophilia and severe muscular pains.
a. Wuchereria bancrofti
b. Trichinella spiralis
c. Plasmodium malariae
d. Enterobius vermicularis
e. Entamoeba coli
b
Members of the genus Babesia are sporozoan parasites of the red blood cell that have recently been found to cause human infections. Infection usually results in a febrile illness associated with hemolysis. Humans become infected from
a. ticks
b. mosquitoes
c. fleas
d. mites
e. none of the above
a
Assuming that a variety of microorganisms might cause pneumonia in AIDS patients, which of the following combination of stains would optimally differentiate the major causes of the pneumonia if a piece of lung tissue was available?
a. Gram’s stain and methylene blue stain
b. Direct fluorescent antibody stain and acid-fast stain
c. Acid-fast stain and Albert’s stain
d. Methylene blue and calcifluor white stain
e. Lactophenol cotton blue and Giemsa’s stain
b
The diagnostic characteristics of Plasmodium falciparum are best described by which one of the following statements?
a. A period of 72 h is required for the development of the mature schizont, which resembles a rosette with only 8 to 10 oval merozoites
b. An important diagnostic feature is the irregular appearance of the edges of the infected red blood cell
c. The signet-ring-shaped trophozoite is irregular in shape with ameboid extensions of the cytoplasm
d. Except in infections with very high parasitemia, only ring forms of early trophozoites and the gametocytes are seen in the peripheral blood
e. Schuffner stippling is routinely seen in red blood cells that harbor parasites
d
Which of the following techniques is employed most successfully for recovering pinworm eggs?
a. Sugar fecal flotation
b. Zinc-sulfate fecal flotation
c. Tap-water fecal sedimentation
d. Direct fecal centrifugal flotation
e. Anal swabbing with cellophane tape
e
A man coughed up a long (4 to 6 cm) white worm and his chief complaint is abdominal tenderness. He reports that he goes to sushi bars at least once a week. The following parasites have been observed in people who eat raw fish: Anisakis, Pseudoterranova, Eustrongylus, and Angiostrongylus. Which of the following would best differentiate the specific parasitic agent?
a. Identification of specific species of fish involved
b. Study of distinctive morphology of the parasite
c. Specific antibody tests
d. Antigen detection in tissues
e. Characteristic signs and symptoms
b
In the United States, certain enteric protozoan and helminthic infections were previously considered to be exotic illnesses related to foreign travel or to contaminated food or water. However, sexual transmission of these diseases has produced a “hyperendemic” infection rate among male homosexuals. The most common infection seen in this group is
a. giardiasis
b. ascariasis
c. amoebiasis
d. enterobiasis
e. trichiuriasis
a
An AIDS patient complains of headaches and disorientation. A clinical diagnosis of Toxoplasma encephalitis is made. Which one of the following antibody results would be most likely in this patient?
a. IgM nonreactive, IgG nonreactive
b. IgM nonreactive, IgG reactive (low titer)
c. IgM reactive (low titer), IgG reactive (high titer)
d. IgM reactive (high titer), IgG reactive (high titer)
e. IgM reactive (high titer), IgG nonreactive
b
Trypanosoma cruzi initially penetrates through the mucuous membranes on the skin and then multiples in a lesion known as a chagoma. In the chronic stage of the disease, the main lesions are often observed in the
a. spleen and pancrease
b. heart and digestive tract
c. liver and spleen
d. digestive tract and respiratory tract
e. heart and liver
b
A woman recently returned from Africa complains of having paroxysmal attacks of chills, fever, and sweating; these attacks last a day or two at a time and recur every 36 to 48 h. Examination of a stained blood specimen reveals ringlike and crescentlike forms within red blood cells. The infecting organism most likely is
a. Plasmodium falciparum
b. Plasmodium vivax
c. Trypanosoma gambiense
d. Wuchereria bancrofti
e. Schistosoma mansoni
a
There are five varieties of cockroaches; the German cockroach, the brown-handed cockroach, the oriental cockroach, theAmerican cockroach, and the smoky brown cockroach. A characteristic of cockroaches is their
a. Transmission of Salmonella
b. toxic sting
c. function as a vector for Borrelia burgdorferi
d. function as a secondary host for rickettsiae
e. easy eradication
a
And Ascaris / other enteric organisms
A medical technologist visited Scandinavia and consumed raw fish daily for 2 weeks. Six months after her return home, she had a routine physical and was found to be anemic. Her vitamin B12 levels were below normal. The most likely cause of her vitamin B12 deficiency anemia is
a. excessive consumption of ice-cold vodka
b. infection with parvovirus B19
c. infection with the fish tapeworm Diphyllobothrium latum
d. nfection with Yersinia
e. cysticercosis
c
Scabies is caused by a small mite that burrows into the skin. The disease is described by all the following statements EXCEPT
a. it is caused by a species of Sarcoptes
b. it is often complicated by secondary bacterial infection
c. it is synonymous with Kawasaki syndrome
d. it is best diagnosed by morphological identification of the mite
e. allergic (asthmalike) reactions to mites are often reported
c
Schistosomiasis is a disease characterized by granulomatous reactions to the ova or to products of the parasite at the place of oviposition. Clinical manifestations include all the following EXCEPT:
a. calcifications in the bladder wall
b. pulmonary arterial hypertension
c. splenomegaly
d. splenomegaly
e. arthropathies
e
Microscporidia are spore-forming, obligate, intracellular parasites. All of the following statements about microsporidia are true EXCEPT:
a. there are four genera of microsporidia
b. microsporidia have been detected only in patients with AIDS
c. Microsporidia can be observed in stool specimens
by the use of special stains
d. Microscoporidia are found in a variety of vertebrate and invertebrate hosts
e. A serologic test is available for microsporidia
b
Giardia lamblia
a. Sigmoidoscopy and aspiration of mucosal lesions
b. Baermann technique
c. Dilution followed by egg count
d. Enzyme immunoassay (EIA)
e. Examination of a cellophane tape swab
d
A fur trapper complains of sore muscles, has swollen eyes, and reports eating bear meat on a regular basis
a. Trichinosis
b. Schistosomiasis
c. Toxoplasmosis
d. Visceral larva migrans
e. Giardiasis
a
Amoebae that inhabit the gastrointestinal tract of man have which stage that is nonmotile, nonfeeding and infective?
a. pseudopod
b. cyst
c. trophozoite
d. cryptozoite
b
A retired Air Force colonel has had abdominal pain for 2 years; he makes yearly freshwater fishing trips to Puerto Rico and often wades with bare feet into streams
a. Trichinosis
b. Schistosomiasis
c. Toxoplasmosis e.
d. Visceral larva migrans
e.Giardiasis
b
Strongyloides larvae
a. Sigmoidoscopy and aspiration of mucosal lesions
b. Baermann technique
c. Dilution followed by egg count
d. Enzyme immunoassay (EIA)
e, Examination of a cellophane tape swab
b
A protozoan with characteristic jerky motility can be found in:
a. Vaginal secretions
b. Duodenal content
c. Blood
d. Biopsied muscle
e. Sputum
a
A tissue dwelling trematode that may be found in feces can also be found in which of the following specimen:
a. Vaginal secretions
b. Duodenal contents
c. Blood
d. Biopsied muscle
e. Sputum
e
A parasite that infects both animals and humans and is carried by the same tick that transmits Borrelia burgdorferi, the bacterium that causes Lyme disease can be isolated from which of the following samples?
a. Vaginal secretions
b. Duodenal contents
c. Blood
d. Biopsied muscle
e. Sputum
c
The eggs of this tapeworm have an operculum at one end and a small abopercular knob at the other. The eggs are undeveloped
a. Diphyllobothrium
b. Dipylidium
c. Paragonimus
d. Hymenolepis
a
Which of the following is a true ameba?
a. Endolimax nana
b. Entamoeba hartmanni
c. Dientamoeba fragilis
d. Iodamoeba butschlii
Either B (True) or C (Flagellate)