clostridium - prac. microbiology

Members of genus Clostridium are relatively large,

anaerobic, Gram-positive, spore forming rods

Many clostridia are members of the normal flora of

the gastrointestinal tracts of humans and animals

Morphology

Thioglycolate broth

Clostridium tetani

Morphology• Gram positive bacilli• Spores (terminal & bulging) Drumstick appearance• Non capsulated• Motile

Culture• Strict anaerobe• Complete haemolysis

C. tetani produces two toxins:

1.Tetanolysin

2.Tetanospasmin

A neurotoxin responsible for the symptoms of

tetanus and is encoded on a plasmid .

Pathogenesis

Treatment:

Human Tetanus Immunoglobulin (HTIG) given IM (human better than horse) - Wound debridement - Metronidazole

Prevention:DPT Vaccine 2, 4 & 6 months & booster doses

1) C. tetani has the following morphology:

a)Gram negative cocci arranged in pairs

b)Gram positive cocci arranged in chains

c) Gram positive club-shaped bacilli

d)Gram positive bacilli with terminal bulging

spores

e)Gram positive capsulated diplococci

2) All of the following are methods of

anaerobic culture EXCEPT:

a)Robertson cocked meat media

b)Anaerobic jar

c) Thioglycolate broth

d) Deep agar

e)Blood agar

3) Clostridium tetani causes:

a) Gas gangrene

b) Tetanus

c) Botulinum food poisoning

d) Antibiotic associated diahrrea

e) Scarlet fever

4) Clostridium tetani:

a) Causes flaccid paralysis

b) Is an aerobic bacillus

c) Has two toxins: tetanolysin and tetanospasmin

d) Produces an enterotoxin as the virulence factor

e) Is treated by a toxoid