MICROBIOLOGY-NON BRANCHING, CATALASE POSITIVE, GRAM-POSITIVE BACILLI (BACILLUS AND SIMILAR ORGANISMS) Flashcards
o Aerobic
o Facultative or strictly anaerobic
o Gram-positive
o Spore-forming rods
Bacillus
What are the characteristics of Bacillus anthracis?
- Aerobic
- Gram-positive box
car-like rods - Nonmotile
- Spore-forming
(endospores) - Nonhemolytic ”comet
tail or Medusa head”
or ground glass
colonies on 5% sheep
blood agar - Rarely found
HABITAT ni Bacillus anthracis
In soil, contracted by various herbivores
MODE OF TRANSMISSION ni Bacillus anthracis
- Direct contact: animal tissue or
products such as wool or hair - Traumatic or insect bites: organisms
or spores - Injection: contaminated drugs
- Ingestion: contaminated meat
- Inhalation: spores; during exposure
to animal products (wool sorter’s
disease) - Person-to-person transmission (rare)
Virulence Factor ni Bacillus Anthracis
Lethal toxin and Edema Toxin
It is primarily responsible for death.
lethal toxin (LT)
It facilitates the transport of other proteins into the cell.
protective antigen (PA)
It is responsible for edema.
edema toxin (ET)
Name the functional enzymes involved in virulence factors.
Lethal factor (LF) and Edema factor (EF).
What type of anthrax accounts for most human infections?
Cutaneous anthrax.
How is cutaneous anthrax contracted?
Through contact with infected animal products and inoculation of endospores through a break in the skin.
What are the symptoms of cutaneous anthrax?
Papule ring of vesicles leading to ulceration (eschar).
How is cutaneous anthrax treated?
it is effectively treated with antibiotics.
How is gastrointestinal anthrax contracted?
By ingestion of endospores.
What are the two forms of gastrointestinal anthrax?
Oral or oropharyngeal (buccal cavity or tongue, tonsils, or pharyngeal mucosa) and gastrointestinal (mucosa of the terminal ileum).
What was inhalation anthrax previously referred to as?
Pulmonary anthrax.
How is inhalation anthrax contracted?
By inhalation of endospores.
What are the initial symptoms of inhalation anthrax?
Flu-like symptoms: fever, chills, fatigue, nonproductive cough, nausea, and vomiting.
What are the advanced symptoms of inhalation anthrax?
Respiratory distress, edema, cyanosis, shock, and death.
What are the common name for inhalation anthrax?
Woolsorters’ disease and ragpickers’ disease.
What are the chest X-ray findings in inhalation anthrax?
Pleural effusion, infiltrates, and mediastinal widening.
How is injectional anthrax contracted?
Through contaminated drugs of abuse (heroin).
What are the symptoms of injectional anthrax?
Severe soft tissue infection and dissemination leading to septic shock.
How should specimens be collected for laboratory diagnosis of anthrax?
Specimens should be collected in leak-proof containers and placed in a secondary container.
Where should samples be taken from for cutaneous anthrax diagnosis?
Samples should be taken from underneath the eschar.