Gram - Part 3c

Question 1

Is a small, gram-negative coccobacillus. It is rarely seen in smears of tissue

Answer 1

FRANCISELLA TULARENSIS

Question 2

Growth requires enriched media containing cysteine.

Answer 2

FRANCISELLA TULARENSIS

Question 3

Grows on commercially available hemin-containing media such as chocolate agar, modified ayer-Martin agar, and buffered charcoal yeast extract (BCYE) agar used to grow Legionella species.

Answer 3

FRANCISELLA TULARENSIS

Question 4

Two major biogroups of strains of FRANCISELLA TULARENSIS

Answer 4

Jellison type A and type B

Question 5

Occurs only in North America, is lethal for rabbits, produces severe illness in humans, ferments glycerol, and contains citrulline ureidase.

Answer 5

Type A

Question 6

Lacks these biochemical features, is not lethal for rabbits, produces milder disease in humans, and is isolated often from rodents or from water in Europe, Asia, and North America.

Answer 6

Type B

Question 7

Is highly infectious: Penetration of the skin (skin abrasion) or mucous membranes or inhalation of 50 organisms can result in infection.

Answer 7

FRANCISELLA TULARENSIS

Question 8

An inflammatory, ulcerating papule develops.
• Regional lymph nodes enlarge and may become necrotic, sometimes draining for weeks (ulceroglandular tularemia).
• Inhalation of an infective aerosol results in peribronchial inflammation and localized pneumonitis (pneumonic tularemia).
• Oculoglandular tularemia can develop when an infected finger or droplet touches the conjunctiva

Answer 8

FRANCISELLA TULARENSIS

Question 9

Lesions on the eyelids may be accompanied by preauricular adenopathy in FRANCISELLA TULARENSIS infection

Answer 9

Yellowish granulomatous lesions

Question 10

Is the standard form of testing of FRANCISELLA TULARENSIS

Answer 10

Agglutination testing either in a tubed format or in microagglutination

Question 11

Are highly suggestive if the history and physical findings are compatible with the diagnosis.

Answer 11

A single-tubed agglutination serum titer greater than 1:160 or a microagglutination titer of greater than 1:128

Question 12

Therapy for 10 days almost always

produces rapid improvement for FRANCISELLA TULARENSIS infection

Answer 12

• Streptomycin or gentamicin therapy

* Flouroquinolones

Question 13

May be equally effective, but relapses occur more frequently in FRANCISELLA TULARENSIS infection

Answer 13

Tetracycline

Question 14

Are nonmotile, Gram-negative coccobacilli with a bipolar appearance on stained smears.
• They are aerobes or facultative anaerobes that grow readily on ordinary bacteriologic media at 37°C

Answer 14

PASTEURELLA MULTOCIDA

Question 15

Oxidase positive and catalase positive but diverge in other biochemical reactions.

Answer 15

Pasteurellae

Question 16

Occurs worldwide in the respiratory and gastrointestinal tracts of many domestic and wild animals.
• It is perhaps the most common organism in human wounds inflicted by bites from cats and dogs.

Answer 16

P multocida

Question 17

The most common presentation is a history of animal bite followed within hours by an acute onset of redness, swelling, and pain

Answer 17

P multocida

Question 18

Considered the drug of choice for P multocida infections resulting from animal bites.

Answer 18

Penicillin G
Tetracyclines
Fluoroquinolones