Question 1

MATCHING
Match the infectious stage of Toxoplasma gondii with the appropriate description.
-Sporozoites

Accepted Answer

A) Crescent-shaped 
B) Oocysts from cat feces 
C) Tissue cysts 
A) Crescent-shaped 
B) Oocysts from cat feces 
C) Tissue cysts B

Question 2

Trichomoniasis is the primary nonviral sexually transmitted disease worldwide.One complication of this infection is:

Accepted Answer

A)  keratitis. 
B)  endometritis. 
C)  meningitis. 
D)  appendicitis. 
A)  keratitis. 
B)  endometritis. 
C)  meningitis. 
D)  appendicitis. B

Question 3

The CSF would reveal which of the following results in infections caused by N.fowleri?

Accepted Answer

A)  Increased glucose, increased protein, and positive Gram stain 
B)  Decreased glucose, decreased protein, and negative Gram stain 
C)  Decreased glucose, increased protein, and negative Gram stain 
D)  Increased glucose, decreased protein, and positive Gram stain 
A)  Increased glucose, increased protein, and positive Gram stain 
B)  Decreased glucose, decreased protein, and negative Gram stain 
C)  Decreased glucose, increased protein, and negative Gram stain 
D)  Increased glucose, decreased protein, and positive Gram stain C

Question 4

MATCHING
Match the infectious stage of Toxoplasma gondii with the appropriate description.
-Tachyzoites

Accepted Answer

A) Crescent-shaped 
B) Oocysts from cat feces 
C) Tissue cysts 
A) Crescent-shaped 
B) Oocysts from cat feces 
C) Tissue cysts

Question 5

Primates, as well as dogs, sheep, and horses, have died of central nervous system (CNS)infections with which organism?

Accepted Answer

A)  Naegleria fowleri 
B)  Acanthamoeba spp. 
C)  Toxoplasma gondii 
D)  Balamuthia mandrillaris 
A)  Naegleria fowleri 
B)  Acanthamoeba spp. 
C)  Toxoplasma gondii 
D)  Balamuthia mandrillaris

Question 6

Tissues suspected of containing Acanthamoeba cysts can be observed using various stains.A cyst that stains black has most likely been stained with the __________ stain.

Accepted Answer

A)  methenamine silver 
B)  periodic acid-Schiff (PAS) 
C)  Giemsa 
D)  Wright 
A)  methenamine silver 
B)  periodic acid-Schiff (PAS) 
C)  Giemsa 
D)  Wright

Question 7

The troph of the motile Trichomonas vaginalis organism measures 7 to 23 microns long and 5 to 15 microns wide.The recommended treatment of choice for this urogenital infection is:

Accepted Answer

A)  tetracycline. 
B)  metronidazole. 
C)  penicillin. 
D)  ketoconazole. 
A)  tetracycline. 
B)  metronidazole. 
C)  penicillin. 
D)  ketoconazole.

Question 8

A 26-year-old woman has an odorous vaginal discharge, lower abdominal pain, and difficulty urinating.Vaginal secretions are collected and sent to the laboratory for examination 3 hours after collection.No motile organisms are observed on the wet preparation; however, Trichomonas vaginalis is suspected.Which one of the following statements explains this discrepancy?

Accepted Answer

A)  The infection is most likely bacterial; therefore a Gram stain should have been performed. 
B)  The specimen should have been refrigerated before examination; consequently, the organism was compromised. 
C)  The time between collection and the microscopic examination was prolonged, resulting in loss of motility. 
D)  No discrepancy is present; this organism in nonmotile. 
A)  The infection is most likely bacterial; therefore a Gram stain should have been performed. 
B)  The specimen should have been refrigerated before examination; consequently, the organism was compromised. 
C)  The time between collection and the microscopic examination was prolonged, resulting in loss of motility. 
D)  No discrepancy is present; this organism in nonmotile.

Question 9

The Acanthamoeba organism is motile and has spinelike pseudopods, a single round nucleus in the cyst form, and a large karyosome in the nucleus of the troph.An estimated 70% of clinical cases of Acanthamoeba keratitis are misdiagnosed as __________ keratitis.

Accepted Answer

A)  bacterial 
B)  fungal 
C)  prion 
D)  viral 
A)  bacterial 
B)  fungal 
C)  prion 
D)  viral

Question 10

Laboratory diagnosis of Trichomonas gondii is confirmed by:

Accepted Answer

A)  Giemsa stain. 
B)  tissue culture. 
C)  serologic testing. 
D)  Western blot. 
A)  Giemsa stain. 
B)  tissue culture. 
C)  serologic testing. 
D)  Western blot.

Question 11

A 15-year-old male was diving in a lake when he inhaled some of the stagnate water.Five days later he was admitted to the hospital, comatose and in critical condition.A cerebrospinal fluid (CSF)specimen was taken, and several motile amoebae were observed.The patient would most likely be diagnosed with which of the following conditions?

Accepted Answer

A)  Granulomatous amebic encephalitis 
B)  Primary amebic meningoencephalitis 
C)  Secondary amebic encephalitis 
D)  Chronic granulomatous meningitis 
A)  Granulomatous amebic encephalitis 
B)  Primary amebic meningoencephalitis 
C)  Secondary amebic encephalitis 
D)  Chronic granulomatous meningitis

Question 12

MATCHING
Match the infectious stage of Toxoplasma gondii with the appropriate description.
-Bradyzoites

Accepted Answer

A) Crescent-shaped 
B) Oocysts from cat feces 
C) Tissue cysts 
A) Crescent-shaped 
B) Oocysts from cat feces 
C) Tissue cysts

Exam 49: Other Protozoa

MATCHING Match the infectious stage of Toxoplasma gondii with the appropriate description. -Sporozoites

Trichomoniasis is the primary nonviral sexually transmitted disease worldwide.One complication of this infection is:

The CSF would reveal which of the following results in infections caused by N.fowleri?

MATCHING Match the infectious stage of Toxoplasma gondii with the appropriate description. -Tachyzoites

Primates, as well as dogs, sheep, and horses, have died of central nervous system (CNS)infections with which organism?

Tissues suspected of containing Acanthamoeba cysts can be observed using various stains.A cyst that stains black has most likely been stained with the __________ stain.

The troph of the motile Trichomonas vaginalis organism measures 7 to 23 microns long and 5 to 15 microns wide.The recommended treatment of choice for this urogenital infection is:

The Acanthamoeba organism is motile and has spinelike pseudopods, a single round nucleus in the cyst form, and a large karyosome in the nucleus of the troph.An estimated 70% of clinical cases of Acanthamoeba keratitis are misdiagnosed as __________ keratitis.

Laboratory diagnosis of Trichomonas gondii is confirmed by:

MATCHING Match the infectious stage of Toxoplasma gondii with the appropriate description. -Bradyzoites

Microbial Taxonomy

Bacterial Genetics, Metabolism, and Structure

Host-Microorganism Interactions

Laboratory Safety

Specimen Management

Role of Microscopy

Traditional Cultivation and Identification

Nucleic Acid-Based Analytic Methods for Microbial Identification and Characterization

Immunochemical Methods Used for Organism Detection

Serologic Diagnosis of Infectious Diseases

Principles of Antimicrobial Action and Resistance

Laboratory Methods and Strategies for Antimicrobial Susceptibility Testing

Staphylococcus Micrococcus and Similar Organisms

Streptococcus Enterococcus and Similar Organisms

Bacillus and Similar Organisms

Listeria Corynebacterium and Similar Organisms

Erysipelothrix Lactobacillus and Similar Organisms

Nocardia Streptomyces Rhodococcus and Similar Organisms

Enterobacteriaceae

Acinetobacter, Stenotrophomonas, and Other Organisms

Pseudomonas, Burkholderia, and Similar Organisms

Rhizobium, Ochrobactrum, and Similar Organisms

Chryseobacterium, Sphingobacterium, and Similar Organisms

Alcaligenes, Bordetella Nonpertussis, Comamonas, and Similar Organisms

Vibrio, Aeromonas, Chromobacterium, and Related Organisms

Sphingomonas Paucimobilis and Similar Organisms

Moraxella and Related Organisms

Eikenella and Similar Organisms

Pasteurella and Similar Organisms

Actinobacillus, Aggregatibacter, Kingella, Cardiobacterium, Capnocytophaga, and Similar Organisms

Haemophilus

Bartonella and Afipia

Campylobacter, Arcobacter, and Helicobacter

Legionella

Brucella

Bordetella Pertussis, Bordetella Parapertussis, and Related Species

Francisella

Streptobacillus Moniliformis and Spirillum Minus

Neisseria and Moraxella Catarrhalis

Overview and General Considerations

Overview of Anaerobic Organisms

Mycobacteria

Obligate Intracellular and Non-culturable Bacterial Agents

Cell Walldeficient Bacteria: Mycoplasma and Ureaplasma

The Spirochetes

Laboratory Methods for Diagnosis of Parasitic Infections: Overview

Intestinal Protozoa

Blood and Tissue Protozoa

Intestinal Nematodes Roundworms

Tissue Nematodes Roundworms

Blood and Tissue Filarialnematodes

Intestinal Cestodes

Tissue Cestodes

Intestinal Trematodes

Liver and Lung Trematodes

Blood Trematodes

Overview of Fungal Identification Methods and Strategies

Hyaline Molds, Mucorales Zygomycetes, Dermatophytes, and Opportunitistic and Systemic Mycoses

Dematiaceous Melanizedmolds

Opportunistic Atypical Fungus: Pneumocystis Jiroveci

The Yeasts

Anti-fungal Susceptibility Testing, Therapy, and Prevention

Overview of the Methods and Strategies in Virology

Viruses in Human Disease

Antiviral Therapy, Susceptibility Testing, and Prevention

Bloodstream Infections

Infections of the Lower Respiratory Tract

Upper Respiratory Tract Infections and Other Infections of the Oral Cavity and Neck

Meningitis, Encephalitis, and Other Infections of the Central Nervous System