med micro microbial disease of the cardiovascular and lymphatic systems

cardiovascular system

circulates blood through the bodys tissues

cardiovascular system includes what?

heart and associated arteries, veins, and capillares

cardiovascular system delivers...

substances to and removes substances from the cells

-emia

infection of the blood

viremia

viruses that cause meningitis

fungemia

fungi in the blood

bacteremia

presence of bacteria in the blood

septicemia

flourishing/growing bacteria in the blood; can lead to decreased blood pressure and septic shock

toxemia

toxins in the blood; intoxication

what are the 3 layers of the heart?

endocardium, myocardium, epicardium

whats the inner layer of the heart?

endocardium

whats the outer layer of the heart?

epicardium

plasma leaves blood capillaries becoming ___________ _________

interstitial fluid

lymph capillaries

transport interstitial fluid (lymph) to lymph vessels (lymphatics) and lymph nodes

lymph nodes have fixed ________, ________, ________

macrophages, B cells, T cells

buboes

swollen lymph nodes

the thoracic duct from the lymphatic system intersects what from the cardiovascular system?

left subclavian vein

septicemia

acute illness due to the presence of pathogens or their toxins in the blood

sepsis

systemic inflammatory response syndrome (SIRS)

lymphangitis

inflamed lymph vessels

severe sepsis

decreased blood pressure and dysfunction of at least one organ

septic shock

sepsis and uncontrollable decreased blood pressure; high mortality if patient progresses to this state

gram negative sepsis

also called endotoxin shock; endotoxins (LPS) cause a serve drop in blood pressure

what are 3 bacteria that are most frequently involved in gram negative sepsis?

Klebsiella spp, E. coli, Pseudomonas aeruginosa

antibiotics can worsen gram negative sepsis by killing bacteria t/f

true

treatment for gram negative sepsis

neutralizing the LPS components and inflammatory causing cytokines

gram positive sepsis

potent exotoxins that cause toxic shock syndrome; hospital acquired infections

potent exotoxins that cause toxic shock syndrome

superantigen exotoxin (TSST)

what are 2 superantigen exotoxin bacteria that cause gram positive sepsis?

Streptococcus pyogenes, Staphylococcus aureus

what are 3 bacteria that are hospital acquired infections that cause gram positive sepsis?

Enterococcus faecium, Enterococcus faecalis, Streptococcus agalactiae

Enterococcus faecium and Enterococcus faecalis

inhabit the colon; colonize wounds and the urinary tract; resistant to many antibiotics

Streptococcus agalactiae

neonatal sepsis

puerperal sepsis

also called puerperal fever and childbirth fever; caused by Streptococcus pyogenes; transmitted to the mother during childbirth

puerperal sepsis infects the ________ and progresses to an infection of the abdominal cavity called _________

uterus; peritonitis

endocarditis

inflammation of the endocardium

subacute bacterial endocarditis

impairs the function of the heart values; caused by alpha-hemolytic streptococci from an oral infection

acute bacterial endocarditis

caused by Staphylococcus aureus

pericarditis

inflammation of the sac around the heart; Streptococci

subacute bacterial endocarditis causes what caused by the immune system response to bacteria?

fibrin platelet vegetations

rheumatic fever

autoimmune complication of S. pyogenes infections

rheumatic fever initially starts as what then subsequentally what?

initially streptococcal sore throat; subsequentally inflammation of the heart valves from an immune reaction against streptococcal M protein

whats a key sign of rheumatic fever?

subcutaneous nodules at the joints

tularemia

caused by Francisella tularensis; zoonotic disease

tularemia transmission

rabbits, ticks, deer flies

tularemia creates an ______ at the site of entry

ulcer

where do bacteria reproduce and what does this cause in tularemia?

bacteria reproduce in phagocytes which enlarges the regional lymph nodes (pus filled)

parenteral skin infection tularemia mortality rate

3%

respiratory infection tularemia (tularemia pneumonia) mortality rate

30%

A 27 year old women has a fever and cough for 5 days. She is hospitalized when her blood pressure drops. Despite aggressive treatment with fluids and massive doses of antibiotics, she dies 5 hours after hospitalization. Catalase negative, gram positive cocci are isolated from her blood. what infections could cause these symptoms?

gram positive sepsis from S. pyogenes

Brucellosis

caused by Brucella spp; undulant fever

Brucella spp.

aerobic gram negative coccobacilli; Brucella abortus, Brucella suis, Brucella melitensis

Brucella abortus

elk, bison, cows

Brucella suis

swine

Brucella melitensis

goats, sheep, camels

Brucellosis transmission

transmitted via milk from infected animals or contact with infected animals

Brucellosis persists where and evades what?

in the reticuloendothelial system; evades phagocytes

symptoms of undulant fever

malaise, night sweats, muscle aches

is undulant fever usually fatal?

no

anthrax

caused by Bacillus anthracis

Bacillus anthracis

gram postive, endospore forming aerobic rod; found in soil

anthrax primarily affects what?

grazing animals

anthrax spores introduced into the body are taken up by __________ and germinate. bacteria enter the bloodstream and release _______.

macrophages; toxins

Bacillus anthracis virulence factors

protective antigen, edema toxin, lethal toxin, amino acid capsule

protective antigen

binds the toxins to target cells, permitting their entry

edema toxin

causes local swelling and interferes with phagocytosis

lethal toxin

targets and kills macrophages

amino acid capsule

avoids an immune response

cutaneous anthrax

endospores enter through a minor cut; sign: depressed, black papule

gastrointestinal anthrax

ingestion of undercooked, contaminated food

inhalational (pulomnary) anthrax

inhalation of endospores, bacteremia/toxemia drives septic shock, death within 36 hours of septic shock

cutaneous anthrax mortality rate

20%

gastrointestinal anthrax mortality rate

50%

inhalational anthrax mortality rate

100%

ischemia

loss of blood supply to tissue

necrosis

death of tissue

gangrene

death of soft tissue

gas gangrene

caused by Clostridium perfringens

Clostridium perfringens

gram positive, endospore forming anaerobic; grows in necrotic tissue, produces toxins that move along muscle bundles

gas gangrene treatment

surgical removal of necrotic tissue and/or use of a hyperbaric chamber

hyperbaric chamber

floods area with oxygen

what are 1% of ER visits annually?

animal bites and scratches (dogs make up 80% of reported bites; cats about 10%)

Pasteurella multocida

gram negative rod; causes severe swelling and pain; pneumonia and sepsis may result

cat scratch disease

caused by Bartonella henselae

Bartonella henselae

aerobic, gram negative; inhabits cat RBCs; multiplies in the digestive system of cat fleas

Bartonella henselae is carried in the blood of what percent of cats?

50%

in cat scratch disease cat claws or mouth get contaminated with what

flea feces

cat scratch disease forms a _________ at the infection site and causes what?

papule; swollen lymph nodes

cat scratch disease is self limiting t/f

true

1 multiple choice option

rat bite fever

transmitted via rat bites

what are the 2 types of rat bite fever?

streptobacillary rat bite fever and spirillar fever

streptobacillary rat bite fever

found in north america; caused by Streptobacillus moniliformis

Streptobacillus moniliformis

filamentous, gram negative, pleomorphic, fastidious

symptoms of streptobacillary rat bite fever

fever, chills, muscle pain

mortality rate of streptobacillary rat bit fever

10%

spirillar fever

caused by Spirillum minus; similar to streptobacillary rat bite fever

plague

caused by Yersinia pestis

Yersinia pestis

gram negative rod

plague transmission

rat flea (Xenopsylla cheopis)

plague is endemic to

rats, ground squirrels, prairie dogs

Yersinia _______ blocks the fleas digestive tract so when a flea bites a human host, ingested blood is regurgutated into host

biofilm