Corynebacterium

Question 1

Yes or no

Gram _______ ________
Motile?
Non sporing?
Capsulated?
Fastidious?

Answer 1

Gram positive rod
No
Yes
No
Yes

Question 2

Whats special about arrangement and appearance

Answer 2

Chinese letter due to snapping division
Metachromatic

Question 3

Babes ernst granules? Mechanism
Demo by which stain

Answer 3

-Metachromatic granules
-Bacteria take up colour different from colour of stain
- Energy stores (polymetaphosphate)

• Alberts stain (toluidine blue+ malachite green+ iodine)
  Neissers stain
  Ponders stain

Question 4

Culture in which medium

Selective medium?

Resistant to?

Answer 4

Loflers enriched medium

Selective:
Macleods medium
Tinsdale medium

Resistant to potassium tellurite (0.03 to 0.04%)

Question 5

Potassium tellurite Agar gives what colour

Answer 5

Black sheen to colonies

Question 6

Biotyping different strains
Whats the colony morphology

Gravis
Intermedius
Mitis
Belfanti

Answer 6

Gravis : Daisy head
Intermedius: Frogs egg
Mitis and belfanti : poached egg

Question 7

Diptheria toxin is susceptible to all cells of body except
Most sensitive to which organs

Answer 7

RBC ( lacks receptor for DT toxin)
Sensitive to Myocardium, Adrenals and Nerves

Question 8

How is toxin produced
What regulates toxin production

Answer 8

Beta phase mediated(lysogenic conversion) production
Iron (Fe) regulates

Question 9

Mechanism of toxin

Answer 9

Inhitibs protein synthesis
Receptors: HB EGF (elongation factor)

Question 10

Vaccination
Inchildren
Adults

Answer 10

Children <7 years : D
Adults and children >7 years: d

Question 11

Diptheria
Transmission?
Clinical features

Answer 11

Droplets
Faucial diphtheria is m/c
Fts: fever, sore throat, white to grey pseudomembrane over tonsil
Cervical lymphadenopathy
Bullet neck (submandibular edema)

Question 12

Complications

Answer 12

1. Asphyxia
2. Myocarditis ( av block, arrythmias) : Circulatory failure (m/c of death)
3. Polymeuropathies (demyelination)

Question 13

Diagnosis

Answer 13

Swabs
- Staining grams and alberts
- Culture : loeflers serum slope, pottasium telurite
- Toxigenicity : Elisa, Elks gel precipitate

Question 14

Elks gel precipitate test is what type of

Answer 14

Double diffusion in 2 dimension

Question 15

Treatment

Answer 15

Antitoxin+ antibiotics + droplets precautions

Antibitocs ( Erythromycin or penicillin for 10-14 days)

Question 16

Antitoxin units for

.1 Pharyngeal/laryngeal disease
2. Nasopharyngeal disease
3. Extensive disease with neck swelling

Answer 16

1. 20k to 40k
2. 40,k to 60k
3. 80k to 1,00,000 / 1,20,000

Question 17

Toxoid administration
Adult /child>7 y
Child < 7 y

Answer 17

1. 3 doses of Td 0,6 weeks, 6 months
2. 3 doses of DT 0, 4 weeks, 8 weeks

Question 18

Vaccination status

Answer 18

• Last dose < 5 yrs back : Toxoid needed only in children in need of 4th dose of DTap
• Uptodate last dose > 5 yrs back : One booster dose
• Not upto date or unkown: Primary vaccine series

Question 19

Schick test

Answer 19

Test susceptibility to diphtheria
Intradermal test: erythema /induration

Question 20

Diphtheroids staining and arrangment

Answer 20

Uniform staining
Pallisade arrangment

Question 21

M/c of diptheria infvetion

Answer 21

C. Ulcerans

Question 22

Phage mediated toxins

Answer 22

A : Shiga toxin
B : Botulinim toxin C and D
C : Cholera toxin
D : Diptheria toxin
E : Erythrogenic toxins A and C