Spore-forming Gram-positive Bacilli Flashcards
are found in the soil
Spores
remain viable in soil for decades. Although spores are naturally in soil from around the world, the organisms are not regularly cultivated from soils.
Spores
Animals, esp. livestock (?), become infected while grazing on grass contaminated with spores which germinate.
goats, sheep, cattle, horses
The vegetative cells multiply and elaborate toxins, which spread in the body cause fatal (?). When the organisms are returned to the soil in animal excrement or carcasses, they sporulate and become a long-term reservoir of infection.
septicemia and toxemia
Transmission to humans is by
direct inoculation, ingestion, or inhalation of spores
Most common form of anthrax in humans, accounting for more than 95% of cases, but the least dangerous form
Cutaneous Anthrax (malignant pustule)
Acquired by inoculation of spores through cut or abrasion of the skin, either from soil or infected animal products
Cutaneous Anthrax (malignant pustule)
begins with a small, itchy lesion resembling an insect bite; in 1-2 days, it develops into a non-painful papule that changes rapidly into a vesicle, then a pustule filled with blue-black edema fluid.
Cutaneous Anthrax (malignant pustule) : Signs and symptoms: Skin infection
blackened crater, typically 1-3 cm in diameter, surrounded by edem.
“black eschar”
Cutaneous Anthrax (malignant pustule) : Signs and symptoms
Lymphangitis and lymphadenopathy
Cutaneous Anthrax (malignant pustule) : Signs and symptoms
fever, malaise, and headache may occur.
is fully developed. Eventually, it dries, loosens, and separates; healing is by granulation and leaves a scar. It may take many weeks for the lesion to heal and the edema to subside.
Eschar
Can lead to sepsis, the consequences of systemic infection—including meningitis—and death in 20% of untreated cases.
Cutaneous Anthrax (malignant pustule)
Extremely rare in humans (accounts for less than 1% of cases)
Gastrointestinal Anthrax (violent enteritis)
Acquired from ingestion of the organism’s spores from contaminated or uncooked meat.
Gastrointestinal Anthrax (violent enteritis)
Characterized by an acute inflammation of the intestinal tract.
Gastrointestinal Anthrax (violent enteritis)
Death occurs in 60% of untreated cases.
Gastrointestinal Anthrax (violent enteritis)
Gastrointestinal Anthrax (violent enteritis) : Signs and symptoms:
- Initially, nausea, loss of appetite, vomiting, and fever
- Followed by abdominal pain, vomiting of blood, and severe (often bloody) diarrhea.
Acquired by inhalation of airborne spores while handling animal products
Pulmonary or Inhalation Anthrax (Woolsorter’s disease)
it develops in handlers of raw animal hair, wool or hides
Pulmonary or Inhalation Anthrax (Woolsorter’s disease)
The incubation period in inhalation anthrax may be as long as 6 weeks.
Pulmonary or Inhalation Anthrax (Woolsorter’s disease)
The fatality rate in inhalation anthrax is high in the setting of known exposure
Pulmonary or Inhalation Anthrax (Woolsorter’s disease)
it is higher when the diagnosis is not initially suspected.
Pulmonary or Inhalation Anthrax (Woolsorter’s disease)
- First symptoms are flu- or common cold-like symptoms including a sore throat, mild fever, and muscle aches.
- Followed by coughing, chest discomfort, shortness of breath, and tiredness — which are manifestations of toxemia, marked hemorrhagic necrosis, edema of the mediastinum, and substernal pain. Sepsis occurs, and there may be hematogenous spread to the gastrointestinal tract, causing bowel ulceration, or to the meninges, causing hemorrhagic meningitis.
Pulmonary or Inhalation Anthrax (Woolsorter’s disease):
Signs and symptoms