Question 1

All of the following are traditional characteristics used to identify mycobacteria except:

Accepted Answer

A) rate of growth. 
B) colony morphology. 
C) gram stain results. 
D) pigmentation. 
A) rate of growth. 
B) colony morphology. 
C) gram stain results. 
D) pigmentation.

Question 2

What is the most sensitive and rapid primary isolation liquid media for Mycobacterium spp.?

Accepted Answer

A) Thioglycollate 
B) Cooked meat 
C) 5% NaCl broth 
D) Middlebrook 7H12 
A) Thioglycollate 
B) Cooked meat 
C) 5% NaCl broth 
D) Middlebrook 7H12

Question 3

What media are recommended for routine culturing of specimens for the recovery of acid-fast bacilli?

Accepted Answer

A) Löwenstein-Jensen and liquid-based media 
B) Middlebrook 7H10 and cooked meat broth 
C) Sabouraud dextrose and LIM broth 
D) Thiosulfate-citrate-bile salts-sucrose (TCBS) and thioglycollate broth 
A) Löwenstein-Jensen and liquid-based media 
B) Middlebrook 7H10 and cooked meat broth 
C) Sabouraud dextrose and LIM broth 
D) Thiosulfate-citrate-bile salts-sucrose (TCBS) and thioglycollate broth

Question 4

What classifies an organism as a multidrug-resistant Mycobacterium tuberculosis?

Accepted Answer

A) Organisms resistant to at least isoniazid and rifampin 
B) Organisms resistant to isoniazid, rifampin, ethambutol, and streptomycin 
C) Organisms resistant to streptomycin and rifampin 
D) Organisms resistant to ciprofloxacin and imipenem 
A) Organisms resistant to at least isoniazid and rifampin 
B) Organisms resistant to isoniazid, rifampin, ethambutol, and streptomycin 
C) Organisms resistant to streptomycin and rifampin 
D) Organisms resistant to ciprofloxacin and imipenem

Question 5

All of the following are biochemical tests for the identification of Mycobacterium spp.except:

Accepted Answer

A) niacin. 
B) nitrate. 
C) catalase. 
D) PYR. 
A) niacin. 
B) nitrate. 
C) catalase. 
D) PYR.

Question 6

What constituent of Löwenstein-Jensen (LJ) medium is added to suppress the growth of gram-positives?

Accepted Answer

A) Carbolfuchsin 
B) Malachite green 
C) Gentian purple 
D) Mercurochrome 
A) Carbolfuchsin 
B) Malachite green 
C) Gentian purple 
D) Mercurochrome

Question 7

How has the treatment of mycobacterial disease changed in light of the multidrug-resistant strains of mycobacteria that are being isolated?

Accepted Answer

A) Antibiotic therapy is started sooner in the course of the disease. 
B) More powerful antibiotics are used to treat mycobacterial disease. 
C) Combinations of three or four drugs are used instead of a single drug. 
D) Patients are hospitalized for the duration of their disease. 
A) Antibiotic therapy is started sooner in the course of the disease. 
B) More powerful antibiotics are used to treat mycobacterial disease. 
C) Combinations of three or four drugs are used instead of a single drug. 
D) Patients are hospitalized for the duration of their disease.

Question 8

A microbiologist is checking the mycobacteria cultures.She notices growth in one tube of Löwenstein-Jensen (LJ) that is a buff color, rough, and seems arranged in a cord.It has taken these organisms 4 weeks to grow.What is the most probable organism?

Accepted Answer

A) Mycobacterium leprae 
B) M.avium 
C) M.tuberculosis 
D) M.marinum 
A) Mycobacterium leprae 
B) M.avium 
C) M.tuberculosis 
D) M.marinum

Question 9

The Centers for Disease Control and Prevention (CDC) recommends all the following drugs for the treatment of Mycobacterium tuberculosis except:

Accepted Answer

A) ethambutol. 
B) isoniazid. 
C) rifampin. 
D) ciprofloxacin. 
A) ethambutol. 
B) isoniazid. 
C) rifampin. 
D) ciprofloxacin.

Question 10

This disease is slowly progressive, malignant, and, if untreated, life threatening.It is characterized by skin lesions and progressive, symmetric nerve damage.Lesions of the mucous membranes of the nose may lead to destruction of the cartilaginous septum, resulting in nasal and facial deformities.What disease is this?

Accepted Answer

A) Hansen's disease 
B) Extrapulmonary tuberculosis 
C) Non-Mycobacterium tuberculosis pulmonary disease 
D) M.xenopi 
A) Hansen's disease 
B) Extrapulmonary tuberculosis 
C) Non-Mycobacterium tuberculosis pulmonary disease 
D) M.xenopi

Question 11

What is the single most important piece of equipment in a mycobacterial laboratory?

Accepted Answer

A) Ultraviolet lights 
B) Covered centrifuge 
C) Biological safety cabinet 
D) CO2 incubator 
A) Ultraviolet lights 
B) Covered centrifuge 
C) Biological safety cabinet 
D) CO2 incubator

Question 12

A sputum culture from a patient in Texas has colonies that grow buff colored colonies in approximately 4 weeks.After exposure to light, the colonies turn intense yellow.This isolate is most likely:

Accepted Answer

A) M.scrofulaceum. 
B) M.kansasii. 
C) M.fortuitum. 
D) M.xenopi. 
A) M.scrofulaceum. 
B) M.kansasii. 
C) M.fortuitum. 
D) M.xenopi.

Question 13

A child visits his doctor because he has had a fever and a nonproductive cough.The child is also short of breath.The doctor orders a routine sputum culture and an acid-fast bacillus (AFB) culture and smear.The smear shows red organisms arranged in ropes.What is the most probable cause of this child's fever and cough?

Accepted Answer

A) Mycobacterium leprae 
B) M.avium 
C) M.intracellulare 
D) M.tuberculosis 
A) Mycobacterium leprae 
B) M.avium 
C) M.intracellulare 
D) M.tuberculosis

Question 14

How are mycobacterial infections transmitted?

Accepted Answer

A) By blood 
B) By fomites 
C) By sexual contact 
D) By air 
A) By blood 
B) By fomites 
C) By sexual contact 
D) By air

Exam 26: Mycobacterium Tuberculosis and Nontuberculous Mycobacteria

All of the following are traditional characteristics used to identify mycobacteria except:

What is the most sensitive and rapid primary isolation liquid media for Mycobacterium spp.?

What media are recommended for routine culturing of specimens for the recovery of acid-fast bacilli?

What classifies an organism as a multidrug-resistant Mycobacterium tuberculosis?

All of the following are biochemical tests for the identification of Mycobacterium spp.except:

What constituent of Löwenstein-Jensen (LJ) medium is added to suppress the growth of gram-positives?

How has the treatment of mycobacterial disease changed in light of the multidrug-resistant strains of mycobacteria that are being isolated?

A microbiologist is checking the mycobacteria cultures.She notices growth in one tube of Löwenstein-Jensen (LJ) that is a buff color, rough, and seems arranged in a cord.It has taken these organisms 4 weeks to grow.What is the most probable organism?

The Centers for Disease Control and Prevention (CDC) recommends all the following drugs for the treatment of Mycobacterium tuberculosis except:

What is the single most important piece of equipment in a mycobacterial laboratory?

A sputum culture from a patient in Texas has colonies that grow buff colored colonies in approximately 4 weeks.After exposure to light, the colonies turn intense yellow.This isolate is most likely:

How are mycobacterial infections transmitted?

Bacterial Cell Structure, Physiology, Metabolism, and Genetics

Host-Parasite Interaction

The Laboratory Role in Infection Control

Control of Microorganisms

Performance Improvement in the Microbiology Laboratory

Specimen Collection and Processing

Microscopic Examination of Materials From Infected Sites

Use of Colony Morphology for the Presumptive Identification of Microorganisms

Biochemical Identification of Gram-Negative Bacteria

Immunodiagnosis of Infectious Diseases

Applications of Molecular Diagnostics

Antimicrobial Agent Mechanisms of Action and Resistance

Antimicrobial Susceptibility Testing

Staphylococci

Streptococcus, Enterococcus, and Other Catalase-Negative, Gram-Positive Cocci

Aerobic Gram-Positive Bacilli

Neisseria Species and Moraxella Catarrhalis

Haemophilus and Other Fastidious Gram-Negative Bacilli

Enterobacteriaceae

Vibrio, Aeromonas, Plesiomonas, and Campylobacter Species

Nonfermenting and Miscellaneous Gram-Negative Bacilli

Anaerobes of Clinical Importance

The Spirochetes

Chlamydia, Rickettsia and Similar Organisms

Mycoplasma and Ureaplasma

Medically Significant Fungi

Diagnostic Parasitology

Clinical Virology

Agents of Bioterror and Forensic Microbiology

Biofilms: Architects of Disease

Upper and Lower Respiratory Tract Infections

Skin and Soft Tissue Infections

Gastrointestinal Infections and Food Poisoning

Infections of the Central Nervous System

Bacteremia and Sepsis

Urinary Tract Infections

Genital Infections and Sexually Transmitted Diseases

Infections in Special Populations

Zoonotic Diseases

Ocular Infections

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