Non-Fermenters and Gram Negative Cocci (Exam 1) Flashcards
How will pseudomonas aeruginosa appear on gram stain
gram negative rod
What are the growth requirements for pseudomonas aeruginosa
temperature 4-42C
Aerobic
Where is pseudomonas aeruginosa found
ubiquitos
What is significant about Pseudomonas aeruginosa capsule
alignate capsule
What does the alignate capsule of pseudomonas aeruginosa form
biofilm
What is the lactose fermentation of pseudomonas aeruginosa
negative
What is the glucose fermentation of pseudomonas aeruginosa
glucose negative
What is the most common infection in cystic fibrosis patients
pseudomonas aeruginosa
Describe the mechanisms for motility in pseudomonas aeruginosa
flagella and pili
What is the oxidase result of pseudomonas aeruginosa
positive
How are pseudomonas aeruginosa infections acquired
opportunistic or nosocomial infections
What is the characteristic color of pseudomonas aeruginosa
green
What is the characteristic smell of pseudomonas
artificial grape scent
How will enterics oxidase test
positive
What are common presentations of pseudomonas aeruginosa infections
pneumonia
folliculitis
swimmers ear
corneal infections
Who gets pneumonia pseudomonas aeruginosa infections
venitlators and CF patients
How do you get pseudomonas aeruginosa folliculitiis
hot tubs
How do you get pseudomonas aeruginos ear inffections
spending a lot of time in water that is contaminated
How do you get corneal infections of pseudomonas aeruginos
contact causes microscopic scratches in the cornea which allows microbes to enter
What type of toxin is seen in pseudomonas
exotoxin A
What is the MOA of the pseudomonas toxin
Ribosyl transferase; Ribosylates EF2 to inhibit protein synthesis which will then kill the cell
What are siderophores
proteins secreted by pathogens that bind iron more tightly that host cells and bring them back to the organism
What enzyme helps pseudomonas move throughout the blood stream
elastase
What is the funciton of elastase
degrades elastin and collagen
What does degredation of elastin and collagen result in
inactivates IgG
inactivates several complement components
inhibits neutrophil function
What type of capsule is seen in pseudomonas aeruginosa
alignate
What is the function of having an aliginate capsule
contributes to biofilm formation
How will phenotypes of pseudomonas aeruginosa change in vivo and in vitro
fresh isolates are mucoidy
within 2 subcultures it will lose the alginate and becomes dry culture
Why does the pseudomonas aeruginosa lose alginate capsule in vivo
to conserve energy and it doesn’t need to survive on the blood agar
Why are CF patients more susceptible to pseudomonas infections in the lungs
CFTR ion channel is not working properly in CF patients
What results in not having a properly functioning CFTR ion channel
mucus becomes very thick, making it harder for cilia to move mucus
What happens because cilia cannot ove the mucus
infections are trapped in the lung
What is the treatment for CF patients
lung transplant
What populations are at risk of pulmonary infections from pseudomonas aeruginosa
cystic fibrosis
ventilator associated pneumonia
those on broad spectrum antibiotics
What population is susceptible to pseudomonas aeruginosa wound infections
impaired immune system, moist surface
burn wounds
surgical wounds
diabetic wounds
What is the main contributor to the antibiotic resistance of pseudomonas aeruginosa
cystic fibrosis patients will have chronic infections that will contribute to antibiotic resistance
What causes the damage to the lungs in cystic fibrosis patients by P. aeruginosa
immune response causes the damage
What are common non-pneumonia infections associated with P. aeruginosa
swimmers ear
folliculitis
eye infections
UTIs
What organism is associated with folliculitis from swimming pools or hot tubs
P aeruginosa
What is bacteremia
bacteria in the blood
What patients are at risk of getting P aeruginosa associated bacteremia
neutropenic patients
diabetics
burned patients
hematologic malignancies
What is the characteristic lesion of bacteremia associated with P aeruginosa
ecthyma gangrenosum
Describe the characteristic lesion of P. aeruginosa
center is necrotic due to elastase encircling blood vessels and making them necrosic
How will Burkholderia cepacia gram stain
gram negative rod
What type of infections will burkholderia cepacia cause
opportunistic and nosocomial infections
lung infections
UTI
What patients are at more risk for lung infections associated with burkholderia cepacia
patients with CF
chronic granulomatous disease
What infection is commonly seen in associateion with pseudomonas aeruginosa
Burkholderia cepacia
Where is bukholderia pseudomallei found
Soil, water, vegetation
What geography is burkholderia pseudomallei found
aoutheast asia, india, africa, australia
What population is at risk of burkholderia pseudomallei
alcoholics
diabetics
chronic renal or lung disease
What disease is associated with Burkholderia pseudomallei
melioidosis
How will melioidosis present
percutaneous infection
pulmonary infection
What are the symptoms of percutaneous melioidosis
suppurative, fever, malaise, lymphadenitis
resolves or potentially sepsis
What are the symptoms of pulmonary meliodosis
mild bronchitis to necrotizing pneumonia
How will acinetobacter baumanni appear on gram stain
gram negative short fat rod “coccobacilli”
Where is acinetobacter baumanni found
ubiquitous: nature and hospital
normal oropharyngeal flora of small % of healthy individuals
What is the oxygen sensitivity of acinetobacter baumanni
aerobic
What is the oxidase test of acinetobacter baumanni
negative
What type of infections are associated with acinetobacter baumanni
nosocomial opportunistic respiratory tract UTI Wounds Septicemia
What populations are at risk of getting infections of acinetobacter baumanni
ventilators
recent surgery
long term antibiotics
How will moraxella catarrhalis appear on gram stain
gram negative diplococci
What is the oxygen sensitivity of moraxella catarrhalis
aerobic
What infections are associated with moraxella catarrhalis
bronchitis
pneumonia
sinusitis
otitis media
What is penicillin sensitivity of moraxella catarrhalis
resistant to penicillin
Why is moraxella catarrhalis resistent to penicillin
produces beta lactamases
Where are moraxella catarrhalis found normally
normal flora of the URT; causes infections when it gets into the lungs
How will neisseria appear on gram stain
gram negative diplococci
What are the O2 requirements of neisseria
aerobic
What is the CO2 sensitive of neisseria
capnophilic: 5% CO2
What are the two strains of neisseria that are important
gonnorhea
meningitidis
How do you differentiate between N. gonorrhoeae and meningitidis
N. meningitidis metabolize maltose
N. gonorrhoeae and meningitidis both use what
glucose
What allows N. meningitidis to be antiphagocytic
capsule
What are the virulence factors of neisseria
Capsule: only meningitidi IgA1 protease LOS: lipooligosaccharide Pili Opa proteins Outer membrane proteins
What type of porins are seen on neiseria
PorA and Por B= N. m
Por B on N. g.
What is the function of porins on neiseria
promotes invasion of epithelial cells
What is the function of Opa proteins in neisseria
adherence and invasion
Does neisseria have LPS
no
What does neisseria have in place of LPS
LOS, no O antigen
What is the pathogenesis of Neisseria
attaches to mucosal cells and invades, multiplies within mucosal cells and moves into subepithelial space
LOS stimulates TNF alpha symptoms
What is the prevalence of gonorrhea
high prevalence, low mortality
What are the reservoirs for gonorrhea
humans
What population is at risk for gonorrhea
higher in african americans
15-24 year olds
How is gonorrhea transmitted
sexual contact
What are the symptoms of gonorrhea in men
urethra
dysuria, frequency, purulent discharge from penis
What are the symptoms of gonorrhea in women
green and yellow discharge, dysuria
What are the long term complications of gonorrhea in men
epididymitis
prostatitis
What are the long term complications of gonorrhea in women
PID
sterility
Fitz Hugh Curtis syndrome
What is Fitz hugh curtis syndrome
infection of the capsule that surrounds the liver
What is gonococcemia
disseminated infection with gonococcus
What are the symptoms of gonococcemia
fever
migratory joint pain
suppurative arthritis: wrists, knees, ankles
pustular rash on extremities
How will gonorrhea present in infants
opthalmia neonaturm; damage to corneas and blindness
How is opthalmia neonatum treated
erythromycin eye drops
How is N. gonorrhoeae diagnosed
gram stain of exudate
culture on Thayer-Martin agar
What does N. gonorrhoeae look like on blood agar
does not grow
What is Thayer Martin agar
chocolate agar with antibiotics that will prevent growth of other organisms
What grows on Thayer Martin agar
Neisseria
How is N. meningitidis transmitted
respiratory droplets
What season is N. meningitidis more common
winter
What are the high risk groups for N. meningitidis
infants
army recruits
college students
complement deficiency
What are the symptoms of N. meningitidis
sudden onset of severe headache, fever, neck stiffness, irritability, photphobia, malaise, nausea and vomiting
What are the long term complications of N. meningitidis
hearing loss
mental retardation
recurrent convulsions
How is N. meningitis diagnosed
gram stain of CSF or blood
Thayer martin agar
What type of neisseria can be grown on blood agar
n. meningitidis
What is meningococcemia
presence of meningococcal organisms in the blood
What are symptoms of meningococcemia
fever, chills, arthralgia, muscle pain, petechial rash
What is petechial rash
pinpoint dots from where the vasculature is leaking
How is meningococcemia diagnosed
diplococci can be recovered from petechial biopsy; gram stain and culture
What occurs to the petechial rash with time
coalesce and appear as blisters
What is the main complication of meningococcemia
Waterhouse-friderichsen syndrome
How does waterhouse-friderichsen syndrome present
bilateral hemorrhage of adrenal glands; DIC (disseminated intravascular coagulation)
coma
death
What are the vaccines against meningits
meningococcal conjugate vaccine
serotype B recombinant vaccine
