Anaerobic gram positive rod bacteria

Question 1

Where can Clostridium be found

Answer 1

There are found in the soil, water, and the intestinal tracts of humans and other animals. Because it has spores it can be found exogenously

Question 2

List the genus of Clostridium

Answer 2

Clostridium tetani= tetanus
C.botulinum
C.perfringens
C.difficile

Question 3

C.tetani

Properties
Morphology
Epidemiology
Clinical disease
Diagnosis
Treatment

Answer 3

Properties= produces neurotoxin; tetanospasmin which interferes with neurotransmission, belongs to the A-B toxin. Responsible for side effects associated with Clostridium

Morphology= Gram-positive, anaerobic, rods produce spores

Epidemiology= Ubiquitous, not a risk to those who are vaccinated, the disease does not induce immunity

Clinical disease= causes muscle spasms, Dysregulatory disorder of alveolar ventilation

Diagnosis= Spatula cannot be tested laboratory as it dies immediately in presence of oxygen.

Question 4

C.Botulinium

Properties
Morphology
Epidemiology
Clinical disease
Diagnosis
Treatment

Answer 4

Properties= Botulinum toxin block the neurotransmitter acetylcholine at the motor nerve synapse .

Morphology= Gram-positive, anaerobic, rods produce spores

Epidemiology= Found in soil. Botulinium toxin is sensitive to heating but resistant to gastric acids.

Clinical disease= Food-borne botulism: initial presentation of blurred vision, dry mouth, constipation, and abdominal pain; progresses to bilateral descending weakness of the peripheral muscles with flaccid paralysis
• Infant botulism: initially nonspecific symptoms (e.g., constipation, weak cry, failure to thrive) that progresses to flaccid paralysis and respiratory arrest
• Wound botulism: clinical presentation same as with food-borne disease, although the incubation period is longer and fewer gastrointestinal symptoms are reported
• Inhalation botulism: rapid onset of symptoms (flaccid paralysis, pulmonary failure) and high mortality from inhalation exposure to botulinum toxin

Diagnosis= Cannot perform a laboratory test as due to the classification being anaerobic it will die in presence of oxygen. However you can perform an A-B toxin test as it produces Botulinum toxin belonging to that family. Sample are detected from feces, serums or the organism is cultured in feces or wounds.

Treatment= antibiotics. toxins are killed by heat so therefore can be destroyed by heating the food for 10 minutes at 60°C to 100°C
• Infant botulism associated with ingestion of contaminated soil or consumption of contaminated foods (particularly honey)

Question 5

C. Perfringens

Properties
Morphology
Epidemiology
Clinical disease
Diagnosis
Treatment

Answer 5

Properties= Produce several types of toxins such as; Alpha toxin is a lecithinase that lyses erythrocytes, platelets, leukocytes, and endothelial cells;

• Beta toxin is responsible for intestinal stasis, loss of mucosa with
formation of necrotic lesions, and progression to necrotising enteritis

• Epsilon toxin increases vascular permeability of the gastrointestinal wall • Iota toxin has necrotic activity and increases vascular permeability acts as a super antigen, stimulating T-lymphocyte activity and massive release of cytokines

Morphology= Gram positive, large rectangle rods, anaerobic , does not contain a lot of spore. This will not be observed.

Epidemiology= Ubiquitous (found in soil, water, GI tract of human and animals )
Type A strains are responsible for human infections
Soft-tissue infections typically associated with bacterial contamination of
wounds or localised trauma
• Food poisoning associated with contaminated meat products (beef, poultry,
gravy) held at temperatures between 5°C and 60°C, which allows the organisms to grow to large numbers

Clinical disease= Localised oedema, accumalation of pus in muscle planes, without muscle necrosis, painful, rapid destruction of muscle tissue with rapid systemic spread and high mortality
• Food poisoning: rapid onset of abdominal cramps and watery diarrhea with no fever, nausea, or vomiting; short duration and self-limited
• Necrotizing enteritis: acute, necrotizing destruction of jejunum with abdominal pain, vomiting, bloody diarrhea, and peritonitis

Diagnoses= • Grows rapidly in blood agar culture as a large, spreading colony surrounded by a zone of β-hemolysis (as it hemolysis the most) and an outer zone of partial hemolysis.

Treatment= If severe should be treated with penicillin. if wound then provide wound care

Question 6

C. difficile

Properties
Morphology
Epidemiology
Clinical disease
Diagnosis
Treatment

Answer 6

Properties = enterotoxin (toxin A) and a cytotoxin (toxin B). he entero- toxin is chemotactic for neutrophils, stimulating the iniltration of polymorphonuclear neutrophils into the ileum with release of cytokines. he cytotoxin causes destruction of the epithelial cytoskeleton.

Morphology= Gram positive rods produce spores

Epidemiology= found in the intestine, Antibiotics reduces the population, the spores can be detected in hospital rooms for infected patients. Highly virulent stains can circulate the hospital and community

Clinical disease= Diarrhea
and Pseudomembranous colitis: most severe form of C. difficile disease with profuse diarrhea, abdominal cramping, and fever; whitish plaques (pseudomembranes) form over intact colonic tissue (seen on colonoscopy)

Diagnosis= Use of culture is slow, and isolation of C. difficile must be further validated by demon- strating that the isolate produces toxin B, so culture is rarely done for routine diagnostic purposes
• Immunoassays for toxins in stool specimens are insensitive and not reliable
• Tests for detection of C. difficile cytoplasmic antigens (i.e., glutamine
dehydrogenase) is sensitive but not specific so should only be used as a
screening assay
• Nucleic acid amplification tests for the toxin genes are the most sensitive and specific
diagnostic tests

Treatment= Antibiotics