Clostridium Botulinum

Clostridium Botulinum


INTRODUCTION:

  • Category A Bioterrorism’s agent
  • Causes a disease of Neuromuscular transmission called botulism
MORPHOLOGY:
  • It is a rod-shaped microorganism.
  • Obligate anaerobe.
  • Tolerates traces of oxygen due to the enzyme called superoxide dismutase (SOD) 
  • Antioxidant defense in cells exposed to oxygen. 
  • Form endospores as a mechanism to produce the neurotoxin. 
  • Neurotoxin production  during sporulation(anaerobic environment).

TOXINS:

  • Eight antigenic varieties of toxin (A–G) are known.
  • Gene for botulinum toxin is encoded by a bacteriophage
  • All varieties neuotoxic except C2 cytotoxic.

Site of action:

  • Peripheral cholinergic nerve endings.
  • Blocks release of Acetylcholine.
  • Principal causes of human illness.
  • A, B, and E
  • Rarely F
  • Poisoning can be prevented by an antitoxin
  • Types A and B have been associated with a variety of foods.
  • Type E predominantly with fish products.
  • Type C(non-neurotoxin) produces limberneck in birds.
  • Type D causes botulism in mammals.
CLINICAL FINDINGS:
Food borne botulism

Pathogenesis

  • Preformed toxin is important in food poisoning.
  • Canned food eaten without cooking.
  • In such foods, spores of C botulinum germinate under anaerobic conditions
  • Vegetative forms grow and produce toxin.

Symptoms

  • Begin 18–24 hours after ingestion of the toxic food
  • Cranial Nerve involvement
  • Dysphagia, diplopia, dysarthria are seen
  • Signs of paralysis are progressive
  • Death occurs from respiratory paralysis or cardiac arrest.
  • Gastrointestinal symptoms are not regularly prominent
  • The patient remains fully conscious until shortly before death.
  • C botulinum and botulinum toxin are found in feces but not in serum.
Infant botulism
  • Due to ingestion of subterminal spores
  • Occur in infant
  • Honey implicated as a possible vehicle for the spores.
  • Sudden infant death syndrome (SIDS) following administration of honey is due to Clostridium botulinum
  • It is assumed that C botulinum spores are in the babies’ food, yielding toxin production in the gut
  • Floppy infant syndrome is seen commonly due to infection with Clostridium botulism
  • poor feeding
  •  weakness
  • signs of paralysis (“floppy baby”).

Wound botulism

  • Toxin is produced in wound.
  • Resembles food bome illness except
  • IP is longer (- 10 days)
  • Gastrointestinal symptoms are lacking.

LAB DIAGNOSIS 

  • The antigenic type of toxin is identified by neutralization with specific antitoxin in mice.
  • C botulinum may be grown from food remains and tested for toxin production.
  • In infant botulism, C botulinum and toxin can be demonstrated in bowel contents but not in serum.
  • Toxin may be demonstrated by passive hemagglutination or radioimmunoassay
  • The electromyogram strength tests are typical.
TREATMENT

Food borne Botulism

No antibiotics

Guanidine hydrochloride and bivalent antitoxin given

Infant Botulism

Supportive care

Human botulism immunoglobulin

Wound Botulism

Antitoxin given

Exam Question
 

INTRODUCTION:

  • Category A Bioterrorism’s agent
  • Causes a disease of Neuromuscular transmission called botulism

TOXINS:

  • Gene for botulinum toxin is encoded by a bacteriophage
  • All varieties neuotoxic except C2 cytotoxic.

Site of action:

  • Peripheral cholinergic nerve endings.
  • Blocks release of Acetylcholine.

Principal causes of human illness.

  • A, B, and E
  • Rarely F

Type C(non-neurotoxin) produces limberneck in birds.

CLINICAL FINDINGS:
Food borne botulism

Source

  • Preformed toxin is important in food poisoning.
  • Canned food eaten without cooking.

Symptoms

  • Begin 18–24 hours after ingestion of the toxic food
  • Cranial Nerve involvement
  • Dysphagia, diplopia, dysarthria are seen
  • Signs of paralysis are progressive
  • Death occurs from respiratory paralysis or cardiac arrest.
Infant botulism
  • Due to ingestion of subterminal spores
  • Sudden infant death syndrome (SIDS) following administration of honey is due to Clostridium botulinum
  • Floppy infant syndrome is seen commonly due to infection with Clostridium botulism
  • poor feeding
  •  weakness
  • signs of paralysis (“floppy baby”).

Wound botulism

  • Toxin is produced in wound.
Don’t Forget to Solve all the previous Year Question asked on Clostridium Botulinum

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this:
WordPress