Acinetobacter, Franciesella, Coxiella, Legionella, and Helicobacter

Question 1

Acinetobacter species generally are generally _______ and only effect __________ patients

Answer 1

Acinetobacter species generally are generally opportunistsand only effect immunocompromised patients

Question 2

What is the morphology of Acinetobacter sp.?

Answer 2

Gram (-)

rod

May pair or chain

Twitiching motility

Question 3

1. What do colonies of Acinetobacter sp.​ look like?
2. How about their biochemical nature?

Answer 3

1. May be large and mucoid or small and non-pigmented.
2. Oxidase negative. Obligate aerobes.

Question 4

Where are Acinetobacter spp. found in nature?

Answer 4

Widespread in soil, water, sewage, feces or colonizing on the skin.

Question 5

List some predisposing factors that may lead to an individual to be more likely to be susceptible to a Acinetobacter infection

Answer 5

• Immunocompromised humans
• Patients on ventilators
• Prior use of broad-spectrum antibiotics
• Use of a urinary tract catheter
• Prior surgery

Question 6

Name the important species which we talked about in class belonging to the genus Francisella?

Answer 6

Francisella tularensis

Question 7

What Dz does Francisella tularensis cause?

Answer 7

Tularemia or “rabbit fever”

Question 8

What are the three biovars of Francisella tularensis

Answer 8

Biovar tularensis

Biovar palaearctica

Biovar novicida

Question 9

Where is Francisella tularensis biovar tularensis found?

Answer 9

Only in North America

Question 10

1. Where is Francisella tularensis biovar palaearctica found?
2. What is the common name for this biovar?

Answer 10

1. distributed widely and is reported primarily from Russia and the Scandinavian countries
2. “Beaver strain”

Question 11

What does Francisella tularensis biovar novicida cause?

Answer 11

Human Dz of tularemia

Question 12

What is the general morphology of Francisella tularensis.

Answer 12

Gram negative

Short rod

Very small (0.2 X 0.7 μm)

Non-motile

Non-encapsulated

May become pleomorphic.

Question 13

What nutrient does Francisella tularensis require to grow?

Answer 13

Cysteine

Question 14

Where would one find Francisella tularensis in nature

Answer 14

Inside ticks, wild rodents and rabbits for biovar tularensis

Inside water rodents and beavers for biovar palaearctica

Question 15

How is Francisella tularensis spread to humans?

Answer 15

Spread is often by contact with infected rabbits or rodents (skinning of infected rabbits is an important source) and via infected ticks.

Gains entry through skin abrasion, conjunctivae, ingestion, or aerosol.

Question 16

Why is Francisella tularensis so dangerous to work with even in the laboratory?

Answer 16

Infectious dose is very low

Organism is one of the most highly infectious known

Question 17

What does the Francisella tularensis Dz cause in rabbits?

Answer 17

Small, necrotic, granulomatous foci in the liver, spleen, and lymph nodes

Question 18

What does the Francisella tularensis ​Dz cause in humans?

Answer 18

Site of entry to the lymph nodes and then to the liver, spleen, bone marrow, and lymphoid tissues, forming granulomatous nodules which ulcerate along the way.

(Ouch.)

Question 19

What are the two forms of Francisella tularensis which you see in humans and how are they contracted?

Answer 19

Pneumonic form - organism is inhaled

Typhoidal form - organism is ingested

Question 20

True or False

Once infected with Francisella tularensis CMI is activated, however infected individuals can relapse.

Answer 20

True

Infected individuals can relapse because of the intracellular organism nature of F. tularensis

Question 21

A human infected with Francisella tularensis is commonly treated with what?

Answer 21

Streptomycin but, Gentamicin is also used effectively

Question 22

To confirm a diagnosis of an animal infected with Francisella tularensis one must?

Answer 22

• Perform an agglutination test on patient serum
• Biopsy specimens of infected soft tissue or lymph nodes and culture
• Blood cultures can be performed if the septicemic form suspected, difficult and dangerous however
• Fluorescent antibody test used to identify the organism itself.

Question 23

What is the primary species of Coxiella which we covered in class?

Answer 23

Coxiella burnetii

Question 24

What are some common morphological features of C. burnetii?

Answer 24

• Small
• Pleomorphic
• Gram-negative
• Obligate intracellular organism
• Forms spore-like structures
• It exists in two antigenically distinct phases that are morphologically identical. Phase I and Phase II

Question 25

What is the common Dz name for which is caused by *Coxiella burnetii*

Answer 25

Q-fever

Question 26

What types of Dz does Q-fever (C. burnetii) cause in rumniants?

Answer 26

Abortions and respiratory tract infections

Question 27

What is the the difference in Phase I vs. Phase II *Coxiella* *burnetii*?

Answer 27

Phase I organisms are highly infectious Phase II organisms are less infectious and arise when cultures are passed repeatedly through eggs or tissue culture

Question 28

When animals are infected with *Coxiella burnetii* an antibody to which phase will be made first?

Answer 28

Phase II

Question 29

What is the primary importance of the Dz C. burnetii?

Answer 29

Infection of humans from contaminated animal products

Question 30

List some ways to treat a C. burnetii infection?

Answer 30

Tetracycline If chronic valvular endocarditis occurs then surgical correction is required

Question 31

What are the signs of Acute Q-fever?

Answer 31

Fever Myalgia Headache Sweating

Question 32

What is the main complication of a chronic Q-fever?

Answer 32

Vegatative valvular endocarditis

Question 33

True or False To prevent *Coxiella burnetii* infection from occuring an inactivated Phase I product is available as a immunization for at risk populations.

Answer 33

True ## Footnote However, before the bacterin can be used in humans, they need to be tested for prior infection. Adverse skin reactions were a problem in humans that were already infected.

Question 34

What is the species name of the *Legionella* genus which we talked about in class?

Answer 34

*Legionella pneumophila*

Question 35

What Dz does *Legionella pneumophila* cause?

Answer 35

**Legionaire's Dz** Pneumonia like Dz (If desseminates infected patients may become delirious, confused and develop an encephalopathy)

Question 36

How does one become infected with *Legionella pneumophila?*

Answer 36

Airborne droplets or water contamination (Think small, crowded spaces like a submarine)

Question 37

List the species of Helicobacter which we covered in class

Answer 37

*Helicobacter pylori* In the lecture notes he mentions: * Helicobacter heilmanni* (humans, cats, dogs) * Helicobacter mustelae* (ferrets)

Question 38

What is the general morphology of *Helicobacter sp.*

Answer 38

Gram-negative Often assume U-shapes, rods, or a rounded form Motile via a tuft of polar flagella and via a corkscrew activity in highly viscous material.

Question 39

List the common Dz caused by *Helicobacter pylori.* (include species its found in)

Answer 39

Acute gastritis and gastric and duodenal ulcers in humans

Question 40

What percent of humans are thought to carry *Helicobacter pylori*

Answer 40

50%

Question 41

What is responsible for the majority of the tissue damage associated by a *Helicobacter sp.*

Answer 41

The urease enzyme generating ammonium ions and CO2

Question 42

How does one diasnose a *Helicobacter pylori* infection

Answer 42

Histology Culture PCR Stool antigen test Serologic test Carbon-labelled urea breath test