MICROEX2 Rod Key Terms

Question 1

Bacillus species are (aerobic/anaerobic) and (spore forming/non spore forming)

Answer 1

Aerobic Spore forming rods

Question 2

Listeria monocytogenes are (aerobic/anaerobic) and (spore forming/non spore forming)

Answer 2

Aerobic Non-spore forming rods

Question 3

Corynebacterium sp. are (aerobic/anaerobic) and (spore forming/non spore forming)

Answer 3

Aerobic Non-spore forming rods

Question 4

Eripselothrix, Lactobaccilus, and Gardnerella are (aerobic/anaerobic)

Answer 4

Aerobic

Question 5

This is a gram stain for ____________.

Supporting evidence?

Answer 5

Bacillus anthracis

Large gram positive (or gram variable) rods

Spores appear as holes inside rods

Question 6

What are the characteristics of Bacillus anthracis?

What are the characteristics of Bacillus anthracis spore?

Answer 6

Aerobic or facultatively anaerobic

Grow on Sheep blood agar (medusa head colonies)

Causative agent of anthrax

“string of pears” when grown on media w/ penicillin

Metobolically inactive, resistant to heat and chemicals (sporulates under aerobic conditions)

Question 7

What are some factors which contribute to the virulence of Bacillus anthracis?

Answer 7

Capsules- antiphagocytis properties

Highly resistant spores

Pathogenicity due to overwhelming septicemia- capillary damage and death

Produces toxins composed of multiple coponents

Question 8

Cutaneous anthrax

Answer 8

Formation of a papule to slack scar (Black Eschar) on skin at the site of spore penitration

Generalized hemorrhage and edema

Rarely progresses to meningitis and/or pneumonia

20% mortality

Question 9

Pulmonary anthrax (Wool Sorter’s Disease)

Answer 9

Sever Respiratory Infection

Begins with malaise and mild fever with nonproductive cough

Progresses to respiratory disress, massive chest edema, cyanosis, and death

Nearly 100% mortality Rate

Question 10

Gastrointestinal Anthrax

Answer 10

Rare form of Wool Sorter’s Disease

Contracted by eating raw meat and/or massive number of spores

Most patients dies from toxemia and overwhelming sepsis

Question 11

“Coryne” is greek for __________.

So the gram stain of Corynebacteria would be…

Answer 11

Club

Gram positive short, slightly curved rods with rounded edges

Question 12

Diphtheroids

Answer 12

non pathogenic corynebacterium

Question 13

Corynebacteria and Diptheria Pathology

Answer 13

Man is habitat

Reservoir: mucous membranes or nose and throat, skin, vagina (can be asymptomatic carrier)

Leathery throat leasion

True intoxication- acts on PNS and heart

1-7 day incubation; low fever, pallo, tachycardia, weakness

Question 14

Prevention and Treatment of Diptheria

Answer 14

Prevention: Vaccine using inactivated diptheria toxoid (Diptheria and Tetanus)

Treatment: antitoxin+ penicillin/erythromycin; revaccination

1 in 10 mortality rate (most sever in those under 5 and over 40)

Question 15

How do we test for diptheria?

Answer 15

Biochemical testing

Whole-cell fatty acid analysis

cell wall diamino acid analysis

16srRNA gene sequencing (refrence labs only)

Question 16

Which organism causes neonatal sepsis and death?

Answer 16

Listeria monocytogenes

Can be passed from mother to child

Question 17

A pecular property of Listeria monocytogenes is its ability to _________.

This leads to contamination of __________,

Answer 17

Multiply at low temperatures

refrigerated food (milk, meat, vegitables held in refrigerator for a long time)

Question 18

Listeriolysin allows Listeria monocytogenes to ….

Answer 18

survive inside phagocytes

Question 19

How can Listeria monocytogenes be isolated?

What are the specimens of choice?

Answer 19

Blood agar (beta hemolytic)

Oxford Media (selective agar): forms black colonies

Specimens of Choice: CSF, blood, placenta, fetal tissue, stool

Question 20

How can Listeria monocytogenes be identified?

Answer 20

Gram Stain: small, gram posittive rods which are sometimes arranged in short chains

Smear: may be coccoid (mistake for streptococci, longer celles mistake for corynebacteria)

Direct Mount: end-over-tumbling

Semi-solid media: umbrella shape patter

Catalase: +

Bile Esculin Salt: +

Question 21

What are the treatment options for Listeria monocytogenes?

Answer 21

Ampicillin and Penicillin

Question 22

Overview of Erysipelothrix rhusiopathiae

Answer 22

Reservoir: turkeys, skine (also rabbits, sheep, birds)

Causes cellulitis (skin infection) following animal bite or handeling raw meat

May lead to endocarditis

Question 23

Identification and Treatment of Erysipelothrix rhusiopathiae

Answer 23

Identification: short gram positive rods

Growth on blood agar

Catalase +

commercial systems (API)

Penicillin

Question 24

Lactobacillus

Normal Flora/reservoir:

Pathogen?

Gram Stain:

Media?

Catalase?

Answer 24

Lactobacillus

Normal Flora/reservoir: mouth, GI tract, female genitals

Pathogen? Usually contaminant, may cause infections in immunnocompromised

Gram Stain: gram positive rods in chains

Media? Blood, Chocolate, CNA, MacConkey (neg)

Catalase -

Question 25

These are _____________ which are stipled __________ cells, and indicate and infection by ___________.

Answer 25

Clue cells

epithelial

Gardnerella

Question 26

Gardnerela Overview

Normal Flora?

Diseases?

Media growth?

Gram Stain?

Answer 26

Gardnerela Overview: CLUE CELLS

Normal Flora: vagina

Diseases: bacterial vaginosis, UTI

Media growth: blood agar (beta), Chocolate, CNA, HBT

Gram Stain: pleomorphic gram variable or gram nagative rods and coccobacilli

Question 27

Which media can be used to grow Corynebacterium diptheria?

Colony appearance?

Answer 27

Tinsdale aga: black colonies with dark bron halo

Cystine-tellurite BA: black or gray colonies

Loeffler’s medium: shows metachromatic granules in cells