Bacteroides and Abscesses Flashcards
what are the characteristics of bacteroides and where can the typically be found
gram negative, anearobes, metabolize complex carbs, found in intestinal flora
what is the predominant member of bacteroides in intra-abdominal absecess
B. fragilis
what is the effect of high amounts of oxygen on beacteroides
toxic and will damage cell wall (aneorbes so only tolerate little o2)
what cavity is the most susceptible to bacteroides of intestinal spillage occurs
the peritoneal cavity
intra-abdominal infections from intestinal spillage result in what type of disease
biphasic disease
why is B. fragilis the most common bacteroide species found in intra-abdominal abscesses
- evades phagocytes
- tolerates initial O2 environment of peritoneal cavity
- thrives once the cavity becomes anaerobic
what are the potential damages caused by intra-abdominal abscesses
- necrosis of neiboring tissues
- reservoirs for bacteria causing sepsis/shock
how do you diagnose an intra-abdominal infection of bacteroides
CAT scan then culture the fluid drained from abscess
how do you treat intra-abdominal abscesses
surgical removal and antibiotics
what enzymes do bacteroides use to tolerate short exposure to O2
superoxide dismutase, catalase
what is the difference b/w sepsis and bacteremia
sepsis is severe systemic illness brought about by microbes, bacteremia is simply prescence of microbes in blood
what are the bodies primary mediators of sepis
- cytokines IL-1 and TNF-x (most important)
- Gram (-) bacteria LPS
- Gram (+) bacteria peptidoglycan
what are the effects of cytokines on vasculature
- vasodilation of vessels
- vascular leakage causing edema
- coagulation
- increase neutrophil expression
hemodynamic derangement eventually causes ?
organs to fail
-MODS or multi-organ dysfunction syndrome known as “shock” phase
what are the physiological characteristics that hemodynamic derangement is in process
decreases blood pressure
increased cardiac output
low organ perfusion
how do you treat sepsis
Antibiotics along with …
- ventilator for O2
- IV fluids fro blood pressure
- adrenergic drugs for increase tissue perfusion
what are the general characteristics for spirochetes
long thin and helical shaped
-cause syphilis and lyme disease
what is the specific sprirochete that causes syphillis
trepona pallidum
what are the 2 major routes for transmission o ftrepona pallidum causing syphillis
transplacental and mucous membranes during sex
what is a syphylitic chancre
initial lesion in primary syphillis
what does trepona pallidum spread systemically
through lymphatic channels
in what stage of syphilis does the bacteria replicate intracellularly and called the “great imitator”
secondary syphillis
treatment of secondary syphilis with penicillan can result in fever and shock called ?
Jarisch-Herxheimer r/x
what stage of syphilis can the bacteria become latent
secondary syphilis
what is the general outcome for tertiary syphilis
destruction of host tissue due chronic inflammation and vasculitis
what is a gummas and what stage of syphilis are they
treponemes+ inflammatory cells in tertiary syphilis
how does tertiary syphilis affect the CNS
ataxic gait, general paresis
how is syphilis diagnosed
detecting antibodies
how do you treat syphilis
penecillan in all stages
what is the specific spirochete that causes lyme disease
borrelia burgdorferi
what is the vector of borrelia burgdorferi, and what triggers the bacteria after being dormant
ticks(bacteria hides in midgut of ticks until triggered), mammal blood is the trigger
how is borrelia burgdorferi spread once the body has an infection
spread via binding to plasminogen and converting it to plasmin
what is erythrema migrans
lesion that forms in localized infection of stage 1 lyme disease
what type of infection is stage 2 lyme disease and what is the mechanism of damage
desseminated infection
-damage caused by hosts response to bacteria via cytokines IL-1 and TNF-x
what are the initial symptoms of stage 3 lyme disease
arthritis
stage 3 lyme disease effects CNS and skin how ?
affects CNS memory, mood, and sleep
-casuse atrophy of skin called acrodermatitis chronica atrophicans
how is lyme disease diagnosed
detecting antibodies
what specific antibiotic is not effective against lyme dieases
penicilan
