ID 6 Flashcards
what does E coli produce?
Beta-galactosidase, which breaks down lactose into glucose and galactose.
EMB results..
1) lactose fermenters grow as purple/black colonies.
2) e coli grows as a green sheen.
meningococci vs gonococci fermentation
- meningococci ferment maltose and lactose
- gonococci ferment glucose
meningococci vaccine?
yes but type B not widely available
other route of infection of gonorrhea? presentation?
perinatally (causes neonatal conjunctivitis)
What is Fitz-Hugh-Curtis caused by?
gonorrhea
other presentation of meningococcemia?
gangrene of toes
treatment for gonorrhea conjunctivits?
erythromycin to prevent blindness
neisseria treatment?
ceftriaxone OR *penicillin G
Fitz-Hugh-Curtis syndrome
o Coded character: Chanelle O’conner/seen in women with PID. Ascending, polymicrobial infection of the female genital tract that can involve the endometrium, uterine tube, and/or peritoneal cavity. House is full of adhesions from the roof to a hippo/infection of the liver capsule and “violin string” adhesions of peritoneum to liver. Perihepatitis is a complication that presents with RUQ pain. She’s profusely sweating + has discharge from her vagina/classic triad is fever + abdominal pain + vaginal discharge. Robby Page is licking up the discharge/caused by gonococci.
o Location: Hallweaver’s house on P street.
H flu structure
small gram negative coccobacillary rod
h flu transmission
aerosols
what are h flu infections usually caused by?
nontypeable, unencapsulated strains since the vaccine.
“cherry red epiglottitis” on endoscopy?
epiglottitis
treatment for h flu mucosal infections (otitis media, conjunctivitis, bronchitis)?
amoxicillin +/- clavulante
treatment for h flu meningitis?
ceftriaxone
prophylaxis for h flu meningitis?
rifampin
when do you give h flu vaccine?
between 2 and 18 months
what does h flu vaccine contain?
type b capsular polysaccharide and PRP (polyribosylribitol phosphate)
other pertussis toxin?
tracheal cytotoxin
Why is pertussis commonly mistaken for viral infection?
Lymphocytic infiltrate resulting from immune response
is legionella infectious?
no
common sources of legionella
1) AC systems + *hot water tanks
how do you detect legionella?
Presence of antigen in urine
legionella treatment
macrolide or *quinolone
legionnaires presentation
severe pneumonia (unilateral, lobar) + fever + GI + *CNS symptoms
legionnaires common in…
smokers + chronic lung disease
what is pontiac fever?
mild flu like syndrome caused by legionella
other pseudomonas toxin
phospholipase C (degrades cell membrane)
pseudomonas capsule…significance
1) mucoid polysaccharide capsule
2) may contribute to chronic pneumonia in CF due to biofilm production
pseudomonas treatments
CAMPFIRE carbapenems aminoglycosides monobactams polymyxins (polymyxin B, colistin) fluoroquinolone ThIRd and 4th generation cephalosporins (caftazidime, cefepimp) Extended-spectrum penicillins (piperacillin, ticarcillin).
e coli virulence factor in cystitis and pyelo
fimbriae (P-pili)
e coli virulence factor in pneumonia and meningitis?
K capsule
EIEC MOA
invades intestinal mucosa and causes necrosis and inflammation
EPEC mechanism
no toxin produced. adheres to apical surface, flattens villi, preventing absorption
EPEC presentation
diarrhea in kids (P for pediatrics)
common sources of EHEC/O157:H7
undercooked meat + *raw leafy vegetables
How do you distinguish EHEC from other e coli?
Doesn’t ferment sorbitol.
other common patient for klebsiella
- diabetics
- abscess in lungs and liver
major cause of bloody diarrhea in kids?
campylobacter
campy animals
dogs, cats, pigs
shigella reservoir
humans only
difference between salmonella and shigella in spread
salmonella can disseminate hematogenously; shigella cell to cell, no hematogenous spread
salmonella type and lab characteristic
H2S production
Salmonella type virulence factor
endotoxin + *Vi capsule
salmonella species virulence factor
endotoxin
shigella virulence factor
endotoxin + shiga toxin
shigella ID50
LOW
affect of antibiotics on shigella vs. salmonella
With salmonella and salmonella type, antibiotics will prolong duration. Shorten duration with shigella.
immune response to s typhi
monocytes
immune response to salmonella species
PMNs in disseminated disease
immune response to shigella
primarily PMN infiltration
GI presentation of S typhi
constipation followed by diarrhea
GI presentation of Salmonella
diarrhea (possibly bloody)
S typhi vaccine?
1) oral vaccine contains live attenuated S type
2) IM vaccine contains Vi capsular polysaccharide
typhoid fever presentation
*rose spots on abdomen + constipation + abdominal pain + fever
typhoid fever treatment
ceftriaxone or fluorquinolone
s typhus unique property
carrier state with gallbladder colonization
Common sources of salmonella
poultry, eggs, pets, turtles
more common cause of salmonella gastroenteritis
non typhoidal salmonella
sources of shigella?
4 F’s: fingers, flies, food, feces
order the severity/toxin production of shigella species
s dysenteriae, s flexneri, s boydii, s sonnei
What is the key to pathogenicity of shigella species?
Invasion; organisms that produce little toxin can cause disease due to invasion.
vibrio media?
grows in alkaline media
vibrio and stomach acidity?
acid labile; requires large inoculum unless host has decreased gastric acidity
