Clostridium

Question 1

Principal Characteristics of Clostridium

Answer 1

Gram positive rods

Question 2

Oxygen requirement & enzyme test results of Clostridium

Answer 2

Anaerobic (some are facultative microaerophilic)
catalase negative
Fermentative

Question 3

Reproduction and motility of Clostridium

Answer 3

Non capsulated
Sporeforming (Location and shape of endospore are consistent with the species
Most are motile (except C. perfringens)

Question 4

Habitat and Ecology of Clostridium

Answer 4

Most are saprophytes
Associated with disease either by direct contamination of wounds or as a transient flora of the GIT
Some species are commensal in the intestinal tract, often causes an oppotunistic infection
Few species are pathogenic

Question 5

Public health aspects of Clostridium

Answer 5

Human botulism is usually traced to improperly processed meat, seafood or canned vegetables

Question 6

Clostridium botulinum

Answer 6

Ruminant, Horse, Fowl - Botulism (Flaccid paralysis)

C & D - cattle
A B E F - humans

Flaccid paralysis
Lamsiekte - cattle
Shaker foal syndrome - horses
limberneck - birds

Question 7

Clostridium chauvoei

Answer 7

Cattle, buffalo, sheep - Blackleg (gangrenous myositis)

Question 8

Clostridium hemolyticum

Answer 8

Cattle - Bacillary Hemoglobinuria

Question 9

Clostridium novyi Type A & B

Answer 9

Type A - Domestic animals - Gas gangrene

Type B - Sheep, cattle - Infectious necrotic hepatitis (black disease)

Question 10

Clostridium perfringens Type A

Answer 10

Animals & man - Gas gangrene; food poisoning

cattle, horses, dog - Hemorrhagic gastroenteritis

Question 11

Clostridium perfringens Type B

Answer 11

Lambs, calves, foals - Lamb dysentery

Question 12

Clostridium perfringens Type C

Answer 12

Calves - Hemorrhagic enterotoxemia

Question 13

Clostridium perfringens Type D

Answer 13

Piglets - Enterotoxemia

Question 14

Clostridium septicum

Answer 14

Domestic animals - Malignant edema

Braxy - scotland
Bradsot - danish

Question 15

Clostridium tetani

Answer 15

Domestic animals - tetanus (spastic paralysis)

Question 16

Clostridium colinum

Answer 16

Quail, young turkey - Ulcerative enteritis

Question 17

Clostridium difficile

Answer 17

Foals - Hemorrhagic necrotizing enterocolitis (pseudomembranous form of colitis)

Question 18

Location and shape of spore of Clostridium tetani

Answer 18

Round & terminally located

distention

Question 19

Location and shape of spore of Clostridium botulinum

Answer 19

subterminally located

distention

Question 20

Location and shape of spore of Clostridium novyi, chauvoei, septicum

Answer 20

oval, eccentric

Question 21

Location and shape of spore of Clostridium perfringens

Answer 21

centrally located

no distention

Question 22

Two modes of toxin production of Clostridium

Answer 22

Extracellular toxins - Readily diffuse out of the cell (almost all clostridial toxins)

Protoplasmic toxins - Released after cell lysis
e.g. C botulinum (A to G), C novyi (alpha toxin) C tetani (tetanospasmin)

Question 23

Two methods of disease production of Clostridium

Answer 23

Intoxication - Ingestion of pre formed toxin or toxins elaborated from a localized lesion
e.g. C botulinum, C hemolyticum, C perfringens

Infection - Infection of the host tissue with subsequent toxin production
e.g. C chauvoei, C novyi, C septicum

Question 24

Subdivisions of Clostridium

Answer 24

Invasive Clostridia - spread from portal of entry causing local and systemic infections
e.g. C perfringens, C novyi, C hemolyticum, C septicum, C chauvoei

Non Invasive Clostridia - little or no power to invade and multiply in living tissue, damage is done after absorption of toxins
e.g. C botulinum, C tetani

Question 25

MOA of botulinum

Answer 25

Blocks the release of neurotransmitter acetylcholine = flaccid paralysis light chain - toxic portion of the toxin, cleaves SNARE protein heavy chain - responsible for internalization and translocation, attachment to susceptible cell

Question 26

Meaning of SNARE and Snap 25

Answer 26

soluble-ethyl-maleimide-sensitive factor attachment protein Synaptosomal associated protein with 25 KD mol wt

Question 27

What part of the SNARE protein does the different type of Clostridium target?

Answer 27

Type C - syntaxin Type A, C, E - Snap 25 Type B D F G - Synaptobrevin

Question 28

MOA of tetanospasmin

Answer 28

Prevents inhibition of contraction = spastic paralysis cleave glutamie 76 & phenyalanine 77of synaptobrevin

Question 29

Resistance of Clostridium

Answer 29

Endospore are resistant to physical influence and disinfectants Killed by boiling for 30 min and autoclaving for 20 min Salt, nitrates and nitrites suppresses germination of C botulinum spores in food

Question 30

Specimen used for Diagnosis of Clostridium

Answer 30

``` Gas gangrene - affected muscles black disease 0 affected liver Enterotoxaemia - small intestinal contents Tetanus - material from wound site Botulism - suspected food, vomitus ```

Question 31

Isolation of Clostridium

Answer 31

anaerobic incubation in BAP Brain heart infusion media Thioglycollate reducing medium