MM Chapter 19

Identify the TE disk on the plate and interpret the results. True or False: TE is an effective antibiotic for this infection.

False

Based on the morphological arrangement, to which genera could the bacteria belong? Select all that apply.

-Micrococcus -Staphylococcus

Which of the following factors could have contributed to Barbara's development of shingles? Select all that apply.

-her daughter and grandchildren moving into her house shortly after the death of her husband -her age, 68

Mycobacterium tuberculosis is a serious pathogen with a variety of unusual structural features. Some of these cellular structures contribute to its virulence (pathogenicity) Match the following virulence factors with a structure of Mycobacterium responsible.

1. Cord factor: -Toxicity to infected cells -Resistance to neutrophil attack 2. Mycolic acid: -Transmission in dried respiratory aerosols -Persistence in tubercles 3. Pilus: -Attachment to tissues

Match the following properties of Mycobacterium with the structural feature responsible for each characteristic.

1. DNA structure: -High G+C 2. Mycolic acid: -Slow growth -Desiccation-resistance -Acid-resistance 3. Thick peptidoglycan wall: -Gram-positive -Bacillus shape 4. Pilus: (nothing)

Mandy suspects the infectious agent is Staphylococcus epidermidis, Staphylococcus aureus, or Micrococcus luteum. Since many strains of S. aureus have acquired resistance to various antibiotics, she decides to do a few more tests to differentiate between the three suspected species. She needs to devise the test strategy first. Drag each set of characteristics to the appropriate bacterial species.

1. Staphylococcus epidermidis characteristics include (coagulase-negative, facultative anaerobe). 2. Staphylococcus aureus characteristics include (coagulase-positive, facultative anaerobe). 3. Micrococcus luteum characteristics include (coagulase-negative, obligate aerobe).

What is the correct sequence of events for the replication of a DNA virus? Arrange the following statements in chronological order .

1. Virions attach to the host cells. 2. Viral DNA is released into the nucleus of the host cell 3. Enzymes required for multiplication of viral DNA are produced via transcription and translation 4. A copy of the DNA is made 5. Capsid and other structural proteins are manufactured 6. Virions are assembled to form complete viruses and are released from the host cell

The test results show that the organism is __________.

Coagulase-positive and a facultative anaerobe.

Classify the infectious agent based on the Gram staining.

Gram-positive cocci

Barbara is worried about spending time with her grandchildren while being treated for shingles. Can her grandchildren contract chickenpox or shingles from spending time with their grandmother?

No. Because of their ages, the grandchildren have most likely been vaccinated against the chickenpox. They are also safe from contracting shingles because they are young.

Compare the results with the classification scheme and determine the infectious agent. The infectious organism is __________.

Staphylococcus aureus

Infections with these symptoms are generally caused by which of the following pathogens?

Streptococcus pyogenes

Drag and drop the appropriate label to the indicated area.

a. bacterial lawn b. zone of inhibition c. antibiotic disk

What disease does the human herpesvirus-1 cause?

cold sores or fever blisters

Based on the observations given, what is the probable diagnosis made by the health care provider?

erysipelas

What is one of the virulence factors associated with the causative agent for this infection?

erythrogenic toxin

What should the course of treatments for this infection entail?

oral antibiotics

Which of the following best describes Barbara's condition?

shingles caused by the herpes zoster virus

A chief concern of the health care provider with an infection such as this one would be which of the following?

the bacteria spreading to the blood (bacteremia) and damaging the heart or the kidneys