Quiz 26 Mycobacterium tuberculosis and Nontuberculous Mycobacteria

What is the optimum culture incubation time for most mycobacteria associated with human disease?

What Mycobacterium spp. fails to grow in vitro?

How are mycobacterial infections transmitted?

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

When designing a mycobacterial laboratory, the designers should build in all the following engineering controls to keep the workers safe except:

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

What is the purpose of the digestion-decontamination processing of specimens submitted for mycobacterial culture?

Decontaminating agents used in the decontamination-digestion process include all of the following except:

All of these stains are commonly used to visualize mycobacteria on a smear except

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

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

Middlebrook 7H10 and 7H11 media are enriched with all of the following except:

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

How long does it take to detectMycobacterium spp. with the BACTEC method?

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?

What are photochromogens?

What are scotochromogens?

What are nonchromogens?

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

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

What component of mycobacteria is used for identification in nucleic acid hybridization assays?

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

What is the antigen used in the purified protein derivative (PPD) skin test?

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?

If a person has had tuberculosis during his or her lifetime, how likely is it that the person will get the disease again?

All of the following are common extrapulmonary infection sites for tuberculosis except:

A 35-year-old man travels on a multidestination vacation over a 2 month period, including lengthy stops in tropical Africa and Southeast Asia. Six weeks after returning come home to the United States, he develops a productive cough, fatigue, weight loss, low-grade fever, and night sweats. What disease should the physician consider as a result of his travel history?

A patient with Hodgkin's disease is feeling bad, so he pays a visit to his physician. The physician's clinical examination reveals submandibular lymphadenitis, subcutaneous nodules, painful swellings, ulcers progressing to abscesses, and draining fistulas. What organism is probably producing these symptoms?

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?

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: