Clostridium

Question 1

Are they aerobic

Answer 1

No. They are obligated to anaerobes

Question 2

Are they motile

Answer 2

Yes. Except for C per fingers , c Ramosum and C tetani.

Question 3

Are they spore forming.

Answer 3

Yes.

Question 4

Are they capsulated.

Answer 4

No. Excpt for c perfinges and c butyrium.

Question 5

What causes gas gangrene

Answer 5

C perfinges
C septicus
C sporogenes
C histolytica

Question 6

Tetanus

Answer 6

C tetani

Question 7

Botulism

Answer 7

C botulinum

Question 8

Antibiotics associated diarrhoea

Answer 8

C. difficile.

Question 9

Culture media for c perfinges

Answer 9

Naegler’s reaction - alpha toxin produces opalescent near the streak line of egg yolk agar
Blood agar- target hemolysis
Mc conkey agar - pink
Litmus milk - stormy fermentation.

Question 10

What is target hemolysis

Answer 10

Inner complete hemolysis surrounded by incomplete hemolysis specific to C perfinges.

Question 11

Toxins produced by c perfinges

Answer 11

Major toxins - alpha beta epsilon and iota
Minor toxins - gamma delta ….
Neuraminidase
Histamine bursting factor
Circulating factor.
Enterotoxin

Question 12

How many major and minor toxins?

Answer 12

4- major
8- minor.

Question 13

Types of clostridia’s wound infections

Answer 13

Simple wound infection
Anaerobic cellulitis
Anaerobic myositis.

Question 14

Treatment of gas gangrene

Answer 14

Penicillin
Clindamycin
Hyperbaric oxygen therapy
Emergency : passive immunisation with anti alpha toxin.

Question 15

Features of gas gangrene

Answer 15

Crepitus
Foul smelling serosanguinous exudate
Shock and organ failure . Therefore it has a high mortality rate.

Question 16

Other infections caused by c perfinges.

Answer 16

Enterotoxin causes food poisoning
Skin and soft tissue infections
Infection of endometrium leading to toxic shock syndrome.

Question 17

Enterotoxin clostridial infection is produced by which type

Answer 17

C perfinges type c producing beta toxin.

Question 18

Main source of infection for clostridium

Answer 18

Soil

Question 19

Is clostridium tetani motile

Answer 19

No

Question 20

Is c tetani capsulated

Answer 20

No

Question 21

Are they spore forming

Answer 21

Yes

Question 22

Toxins of c tetani

Answer 22

Exotoxins -
Tetanolysin
Tetanospasmin

Question 23

Tetanolysin features

Answer 23

They are heat labile and oxygen labile. They are not pathogenic

Question 24

Tetanospasmin features

Answer 24

They are heat labile but oxygen stable. They inhibit the inhibitory neurotransmitter such as GABA and glycine.

Question 25

Features of tetanus

Answer 25

It first affects the facial muscles and jaws because of shorter neural distance It causes neck rigidity and trismus. Complications- risus sardonicus - constant grinning Opisthotonus - posture complications Respiratory muscle spasm - airway obstruction

Question 26

How do you detect Tetanolysin

Answer 26

In vitri hemolysis inhibition test

Question 27

Tetanospasmin detection

Answer 27

In Vigo mouse inoculation test

Question 28

How do you know if it is proteolytic

Answer 28

RCM broth turns black and has a foul odour

Question 29

Blood agar findings for c tetani

Answer 29

Alpha hemolysis that later turns to beta hemolysis.

Question 30

Why is antibiotics not suggested for tetani

Answer 30

Even though metronidazole is recommended , it is of no use because it does not act against the toxins produced. Antibiotic are useful only to reduce the number of organisms and prevent further release of toxins.

Question 31

Passive Immunisation for tetani

Answer 31

Human tetanus immunoglobulin ( more preferred) Anti tetanus serum ( may produce serum sickness and anaphylaxis )

Question 32

Active immunisation for tetani

Answer 32

Tetanus toxoid. Can be adsorbed or plain. Adsorbed increases the time of immunity.

Question 33

Tetanus immunisation dosage

Question 34

Is c botulinum motile

Answer 34

Yes

Question 35

Is cbitulinum capsulated

Answer 35

No

Question 36

Toxin name and MOA

Answer 36

botulinum toxin. They inhibit acetylcholine release leading to flaccid paralysis. However it recovers after 2-4 months as new neuronal terminals develop.

Question 37

Can botulinum toxin be used in treatment

Answer 37

Yes. In TGN , myoclonus, blepharospasm.

Question 38

Types of botulism

Answer 38

Food borne( canned food) Wound borne Infants ( honey given to children less than 1 yr ) Iatrogenic ( overdose of toxin)

Question 39

Treatment of C. difficile

Answer 39

Metronidazole

Question 40

Antibiotics causing clostridial diarrhoea

Answer 40

Cephalosporins Clindamycin Fluoroquinones Ampicillin