MICROBIAL DISEASE OF THE VASCULAR SYSTEMS

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MICROBIAL DISEASE OF THE VASCULAR SYSTEMS

• BLOOD INFECTION SEPTICEMIA
• Blood is normally sterile, but moderate numbers
  of microbes are able to be tolerated and
  destroyed by the immune system.
• If defenses fail and microbes multiply in the
  blood, septicemia, or blood poisoning results
• _________________ - red streaks of inflamed lymph
  vessels
• ______________, constriction of small A V,
  peripheral anoxia, rapid breathing and heart
  rate, lowered B.P. - coma- death
• _______________ are the most frequent bacteria
  symptoms are related to endotoxin release
• Antibiotics may aggravate the problem by killing
  many more bacteria and releasing more endotoxins
• Bacteria are often introduced as nosocomial
  infection, via catheters, feeding tubes
• _________________ infection which may lead to
  septicemia
• Uterine infection after childbirth or abortion,
  due to poor hygiene of medical workers
• Streptococcus pyogenes is the most frequent agent

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HEART DISEASE

• BACTERIAL ENDOCARDITIS
• Inflammation of the inner membrane lining the
  heart muscle and valves
• Streptococcus and Staphylococcus present in
  infections at remote sites are usually
  responsible for these conditions.
• _____________________ are most common
• Bacteria find their way into the blood and then
  attach onto the heart valves
• Commonly, infected valves were already damaged by
  other disease conditions, or congenital defects
  (rheumatic fever, syphilis)
• Penicillin is often given prophylactically during
  tonsil or tooth surgery to try to kill bacteria
  that might enter the blood stream
• PERICARDITIS
• ______________ can also cause this condition

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TULAREMIA/GAS GANGRENE

• TULAREMIA
• First observed in ground squirrels in Tulare
  County in 1911.
• Microbe responsible is __________________
• Gram -ve, facultatively anaerobic pleomorphic
  rod.
• Disease can arise if microbes are
  __________________________________________
• Disease __________ varies with each type of
  introduction of microbes.
• First sign - ulceration and inflammation at the
  site of infection, mouth and throat infections
  are seen if the infection came from eating
  infected meat.
• GAS GANGRENE
• Wounds losing their blood supply ( ischemia)
  become anaerobic
• Ischemia - tissue death or necrosis, when the
  tissue is soft, the process is known as gangrene.
• Dead cells provide a rich nutrient medium for
  anaerobic bacteria
• Clostridium perfringens is a common agent of
  infection
• CO2 and H2 gas may be produced as the bacteria
  ferment CHOs
• Toxins are produced and move down nerves, killing
  more cells and making further necrotic tissue
• Amputation or other forms of removal of the dead
  tissue are required or death will result.
• Internal gas gangrene can sometimes be treated in
  an oxygen-rich hyperbaric chamber
• Wound cleaning and precautionary antibiotic
  treatment are the most effective preventive steps

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PLAGUE

• PLAGUE
• Known as the Black Death because of blackish blue
  hemorrhages seen thru the skin of infected
  individuals
• 14th century - destroyed 25 of the human
  population and 10 million died in India around
  the turn of the century
• 10-15 cases per year in the U.S.A., 25 mortality
  rate
• Gram -ve rod, Yersinia pestis causes the disease
• Rats were the primary reservoir, now the disease
  is endemic in wild squirrels, prairie dogs and
  chipmunks
• Transmission - Bites from fleas feeding on
  infected animals or broken skin contact with
  tissues from the infected animal
• Bacteria multiply in lymph and blood, hiding in
  phagocytic cells and escaping the immune response
• Highly virulent microbes are liberated causing
  overwhelming infection
• Lymph nodes become hugely swollen, known as
  buboes, 50-75 mortality untreated
• Lung infection results in a highly contagious
  form, pneumonic plague, almost 100 mortality and
  death usually within 3 days
• Streptomycin and tetracycline are commonly
  effective treatments if bacteria are isolated and
  identified
• Recovery leads to immunity. Vaccine available for
  health workers only, not very effective
  long-term.