CORYNEBACTERIUM

Question 1

CORYNEBACTERIUM MORPHOLOGY AND IDENTIFICATION

1. With irregular swellings at one end (__________)
2. • ________ (beaded appearance

Answer 1

club shaped
beaded appearance

Question 2

CORYNEBACTERIUM
PATHOGENESIS
Respiratory tract in wounds, or on the skin of infected persons or normal carriers (nasopharynx)

MOT: __________ or contact with susceptible individuals

Answer 2

droplets

Question 3

CORYNEBACTERIUM
DIPTHERIA TOXIN

1. ___________ – bind to receptor (CD-9 & heparin-binding EGF); triggers entry of toxin into cell via receptor-mediated endocytosis
2. ____________ – inactivate EF-2 (in presence of NAD) inhibiting polypeptide chain elongation

Answer 3

1. Fragment B
2. Fragment A

Question 4

CORYNEBACTERIUM
PATHOLOGY
Destruction of epithelium + superficial inflammation becomes necrotic epithelium embedded in exuding fibrin, RBC, and WBC forming grayish __________

Answer 4

pseudomembrane

Question 5

CORYNBACTERIUM DIPTHERIAE
DIAGNOSTIC LAB TEST
1. ________ - detects diptheria bacilli with high accuracy and useful for early diagnosis and surveillance

2. __________ - rules out hemolytic streptococci
3. __________ - selective media and detects isolates bacteria (black colonies with brown halo)

Answer 5

1. Dacron swab
2. Culture on BAP
3. Culture in CTBA or modified Tinsdale’s medium

Question 6

CORYNEBACTERIUM TREATMENT

1. _______ & ______ - inhibits growth of bacilli and help eliminate co-existent strep and C. diphtheriae from respiratory tract of patients or carriers
2. ___________ _ early administration against toxin formed at site of entry and multiplication

Answer 6

1. Penicillin and Macrolides
2. Diptheria Antitoxin

Question 7

OTHER CORYNEFORM BACTERIA
1. _________ - can cause disease similar with clinical diptheriae ; (+) carriage in domestic pets
2. ____________ - carry diptheria tox gene; rarely cause disease in humans
3. ___________- (+) beta hemolysis on blood agar; catalase negative; grow in media selective for streptocci; associated with pharyngitis in adolescent and adults

Answer 7

1. C. ulcerans
2. C. pseudotuberculosis
3. Arcanobacterium haemolyticum

Question 8

LISTERIA MONOCYTOGENES
VIRULENCE FACTORS
1. ________ - facilitate bacterial binding to host cells
2.________ interact with E-cadherin (receptor on epithelial cells) promoting phagocytosis into epethelial cells
3. _________ - released due to low pH inside phagolysosomes; disrupts phagosome membrane

Answer 8

1. adhesins
2. cell wall surface proteins 3. (internalins A and B)
   listeriolysin o (LLO)

Question 9

LISTERIA MONOCYTOGENES
VIRULENCE FACTORS
4. __________ - together with listeriolysin O, lyses membrane of phagolysosome
5. ________ - surface protein induce cell actin polymerization propelling listeriae to the cell membrane
6.____________- elongated protrusions ingested by adjacent epithelial cells, macrophages, and hepatocytes and then released
7.___________- obtain iron from transferrin

Answer 9

4. Phospholipases
5. Act A (Actin Assembly inducing protein)
6. Filopods
7. Siderophores

Question 10

LISTERIA MONOCYTOGENES
CLINICAL FINDINGS
Early-onset syndrome
Result of in utero infection;
disseminated form of the disease
Death may occur before or after
delivery

Answer 10

Granulomatosis Infantiseptica

Question 11

LISTERIA MONOCYTOGENES
CLINICAL FINDINGS
In immunocompromised persons
Meningoencephalitis
Insidious to fulminant
Bacteremia
Focal infection

Answer 11

Food Borne Listeriosis

Question 12

LISTERIA
TREATMENT
Ampicillin, erythromycin or IV trimethoprim-sulfamethoxazole

Recommendation: _____________ + _______

____________ is the Drug of choice for CNS infection in patients allergic to PEN

Answer 12

Recommendation: Ampicillin and Gentamicin
Drug of choice for allergic to PEN: Trimethoprim

Question 13

BRUCELLA
GENERAL CHARACTERISTICS
1. Gram-negative _______, often poorly or irregularly staining

2. Aerobic, nonmotile, non-
   spore forming

Answer 13

coccobacilli

Question 14

BRUCELLA
VIRULENCE FACTORS
1. _________ - Inhibit phagosome-lysosome fusion & complement deposition – allows intracellular survival
2. _________ - Defense against oxidative burst activity – allows intracellular survival
3. ________- Allows Brucella to reach and replicate within a cell’s endoplasmic reticulum
4. __________ - Help release bacteria from a cell & induce cell necrosis

Answer 14

1. Lipopolysaccharide
2. Superoxide dismutase & catalase
3. Type IV secretion system
4. Hemolysin

Question 15

BRUCELLA
PATHOLOGY
___________ to abscesses in lymphatic tissue,
liver, spleen, bone marrow & other parts of RES
-> Epithelioid cells, giant cells, central necrosis, peripheral
fibrosis

Answer 15

granulomatous nodules

Question 16

PASTEURELLA
Characteristics
1. Non-motile
2. Gram (-) _______ with _______- bipolar appearance
3. oxidase and catalase (+)

Answer 16

coccobacilli with bipolar appearance

Question 17

PASTEURELLA
Pathogenesis and Clinica
1. Most common organism in human wounds due to bites from _____ and ______
2. May be part of normal human microbiota

Answer 17

wounds due to bites from cats and dogs

Question 18

PASTEURELLA
Animal bite within hours becomes Redness, swelling and pain__________ and
Regional LAD (variable)

Answer 18

low-grade fever