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Bug Parade
Toxigenic and Extracellular Bacteria
181
Microbiology
Professional
03/11/2014

Additional Microbiology Flashcards

 


 

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Term
Vibrio cholerae biology
Definition
comma-shaped, G- rod, 2 chromosomes, oxidase+, single polar flagellum, akali tolerant, O1 and O139 strains cause disease
Term
Vibrio cholerae virulence factors
Definition
mucinase, flagellum, pili (adherence and prevent elimination)
cholera toxin and regulation by ToxR
Term
Vibrio cholerae pathogenesis
Definition
entry: fecal-oral, large inoculum
attach: epithelial of small intestine, no invastion
incubate: 2-3 days
Symp: abrupt onset, non-inflammatory diarrhea and vomit, "rice water" stool, rapid fluid loss, dehydration
Resolve: self-limiting if dehydration controlled, 60% mortality w/o tx
Term
Vibrio cholerae epidemiology
Definition
underdeveloped countries due to poor sanitation
U.S.: contaminated seafood, travel to endemic areas
Term
Vibrio cholerae diagnosis
Definition
culture stool: grows on alkaline pH
clinical: exposure, diet, diarrhea volume and description, outbreak detection
Term
Vibrio cholerae treatment
Definition
fluid and electrolyte replacement
antibiotics: erythromycin, (tetracylcine)
Term
Vibrio cholerae prevention
Definition
no vaccine available
sanitary water sources
don't eat poop
Term
Vibrio parahaemolyticus biology
Definition
curved, G- rod, halophilic, motile
Term
Vibrio parahaemolyticus virulence factors
Definition
cytotoxins with enterotoxic activity
Term
Vibrio parahaemolyticus pathogenesis
Definition
self-limiting gastroenteritis
incubate: 5-72 hours, abrupt onset
watery diarrhea and vomiting
Term
Vibrio parahaemolyticus epidemiology
Definition
seafood-associated diarrhea (summer)
case clusters (common source)
Term
Vibrio parahaemolyticus therapy
Definition
supportive only
antibiotics - only if severe, doxycycline, criprofloxacin
Term
Vibrio vulnificus biology
Definition
curved, G- rod, halophilic, motile
Term
Vibrio vulnificus virulence factors
Definition
acidic polysaccharide capsule (antiphagocytic, resist C')
pore-forming cytotoxin, proteases
Term
Vibrio vulnificus pathogenesis
Definition
primary sepsis: contaminated seafood causes invasive gastroenteritis, invades gut wall to blood stream, mortality >40% w/ tx
rapid progress cellulitis: contaminated wound, inflammation of skin and subcutaneous tissue, rapid spread causes blisters and bullae (flaccid), bloodstream access, sepsis
Term
Vibrio vulnificus epidemiology
Definition
U.S.: costal waters, contaminated seafood or water
Increased risk: liver disease, alcoholism, hermochromatosis, hematopoietic disease, or other chronic diseases
Term
Vibrio vulnificus treatment
Definition
antibiotics: doxycyline, cirprofloxacin
support for sepsis
Term
Vibrio vulnificus prevention
Definition
avoid undercooked seafood
proper wound care
Term
Helicobacter pylori biology
Definition
spiral/S-shaped G-, motile, microaerophile, oxidase+, catalase+
Term
Helicobacter pylori virulence factors
Definition
flagella (polar tuft)
mucinase, adhesions (non-pilus)
hemagglutinin, sialic acid-binding protein, Lewis blood group adhesion, cytotoxins, urease (breaks urea to CO2 and NH4)
Term
Helicobacter pylori pathogenesis
Definition
entry: fecal-oral
target: stomach
disease: chronic gastritis
90% of duodenal ulcers, 50-80% of gastric ulcers
predisposes to gastric carcinoma and gut-associated lymphoma
Term
Helicobacter pylori epidemiology
Definition
50% of U.S. population has
Term
Helicobacter pylori diagnosis
Definition
non-invasive: urea breath test, serology, stool Ag test
invasive: biopsy for histology and rapid urease test
Term
Helicobacter pylori treatment
Definition
cocktail antibiotics (metronidazole + tetracyline or macrolide), acid-inhibitor, anti-inflammatory med
Term
Campylobacter jejuni biology
Definition
curved, G- rod, motile, microaerophilic, oxidase+, catalase+, grows at 42* but not at 25*C
Term
Campylobacter jejuni virulence factors
Definition
toxins, adhesins
LPS O-Ag sialic acid mimices ganglioside on neural tissue (Abs to will cause autoimmunity)
Term
Campylobacter jejuni pathogenesis
Definition
entry: oral
disease: invasive, inflammatory gastroenteritis
incubate: 1-7 dyas
symps: fever, chills, myalygia, headache, then acute onset of watery diarrhea (+/- blood), cramps
mild to severe
sequelae: Guillan-Barre syndrome (nerve autoimmune disease)
Term
Campylobacter jejuni epidemiology
Definition
leading cause of bacterial-food poisoning
undercooked/raw poultry and unpasteurized milk
Term
Campylobacter jejuni diagnosis
Definition
stool culture, selective media: grows at 42* but not 25*C
gram-stain (G- rod)
Term
Campylobacter jejuni treatment
Definition
supportive
severe, antibiotics: tetracycline, macrolides, quinolones
Term
Campylobacter fetus biology
Definition
curved, G- rod, motile, microaerophilic, oxidase+, catalase+, grows at 25* but not 42*C
Term
Campylobacter fetus virulence factors
Definition
protein capsule (S-layer)
Term
Campylobacter fetus pathogenesis
Definition
entry: oral route
disease: systemic infections (sepsis) that follow gastroenteritis episodes
Term
Campylobacter fetus epidemiology
Definition
rare in U.S., usually only immunocompromised
contaminated food (undercooked) or water
Term
Campylobacter fetus diagnosis
Definition
stool culture, selective media: grows at 25* but not 42*C
gram-stain (G- rod)
Term
Campylobacter fetus treatment
Definition
antibiotics: tetracyclines, macrolides, quinolones
support for sepsis
Term
Clostridium perfringens biology
Definition
large, G+ bacilli, spore forming, anaerobes, hisototoxic, non-motile, aerotolerant, 5 types (A-E) based on toxins, Type A is most human infections
Term
Clostridium perfringens virulence factors
Definition
major toxins: alpha, beta, epsilon, iota
enterotoxin is superantigen for T cells
Term
Clostridium perfringens pathogenesis
Definition
Gastroenteritis: oral entry, large inoculum, target small intestine, heat-labile enterotoxin from spores, adominal cramps, watery diarrhea

Cellulitis: subcutanenous tissue infection, multiply and release toxins, discoloration, gas formation, bullae, edema, non-pain, no necrosis
Supprative myositis: faciitis, wound contam with spores, toxin release, accumulation of pus, no necrosis or systemic involvement

Clostridial myonecoris: gas gangrene, wound with spores, toxin release, acute onset, severe pain, extensive muscle necrosis, skin discoloration, tachycardia, fever, intravascular hemolysis, shock, organ failure, 40-100% mortality

Necrotizing Enteritis: caused by Type C, necosis in jejunum, Beta-toxin, acute abdominal pain, vomiting, bloody diarrhea, perforation -> peritonitis and shock
Term
Clostridium perfringens epidemiology
Definition
soft tissue: wound, trauma, surgery, vascular insufficiency increases risk

gastro: comtaminated meats, cook then cooling period (spores germinate and multiply)
Term
Clostridium perfringens diagnosis
Definition
soft tissue: large G+ rods, lack of WBC invasion, gas in tissues (Xray or palp)

gastro: recovery from food or feces
Term
Clostridium perfringens treatment
Definition
soft tissue: penicillin

gas gangrene: surgical debridement, amputation, penicillin, clindamycin, metronidazole

gastro: supportive, no antibiotics
Term
Clostridium perfringens preventation
Definition
proper wound care
judicious prophalaxis
refrigerate food quickly, heat leftovers thoroughly
Term
Clostridium difficile biology
Definition
large, G+ bacilli, spore forming, strict anaerobes, hisotoxic, oxidase+, catalase+, motile
Term
Clostridium difficile virulence factors
Definition
adhesins for colonic epithelial
toxin A: damage tight junctions, increase permeability of gut, chemoattract for PMNs
toxin B: cytotoxin, destroys cytoskeleton, kills enterocytes
spores: longer survival in hospital setting
Term
Clostridium difficile pathogenesis
Definition
disease: antibiotic associated colitis
endogenous or exogenous infectio bns
entry: oral-fecal (spores or germination)
bacteria adhesins and toxins cause local damage with inflammation, self-limiting

Pseudomembranous colitis: fever, abdominal pain, bloating, cramping, fulminant watery diarrhea with WBC, inflammatory plaques
can progress to Toxin Megacolon
Term
Clostridium difficile epidemiology
Definition
high association with antibiotic use (5-10 d after start or 2-10weeks after finish)
hospitalized and elderly
Term
Clostridium difficile diagnosis
Definition
detect toxin A or B in stool (immunoassay)
Term
Clostridium difficile treatment
Definition
discontinue causitive antibiotic
tx antibiotic: metronidazole or ORAL vancomycin
Term
Clostridium difficile prevention
Definition
rapid diagnosis
contact precautions
rigorous hospital room cleaning
Term
Clostridium botulinum biology
Definition
large, G+ bacilli, spore forming, strict anaerobes, neurotoxic, motile, 7 serotypes (A-G)
Group I: A, B or F
Group II: B, E or F
produce botulinum toxin
Term
Clostridium botulinum virulence factors
Definition
spore formation
botulinum toxin: flaccid paralysis, heat-labile, AB toxin
B toxin - protects from degradation in gut
A - Zn-dependent endopeptidase; targets NMJ, no ACh release, flaccid
Term
Clostridium botulinum pathogenesis
Definition
Food-borne: intoxication; ingestion of toxin, enters blood stream, goes to peripheral nerves; incubate 12-71 hrs; dry mouth, diplopia, ptosis, pupil dilation, dyphagia, nausea, vomit; progresses to bilateral, descending wekanes; death from resp. failure; toxin binds irreversible, long reovery

Infant: infection; ingest spores, infects gut (poor NF); initially: constipation, weak cry, lethargy, poor feed/drink; progress: flaccid paralysis, floppy baby, respiratory distress; 1-2% die, in SIDS

Wound: infection; spores contaminate wound, produce toxin; incubate 4-14 days; similar to food-borne plus fever, leukocytosis, and co-infections
Term
Clostridium botulinum epidemiology
Definition
Food-borne: canned food, preserved fish
Infant: honey, dust
Wound: IV drug users
Term
Clostridium botulinum diagnosis
Definition
Food-borne: bioassay for toxin activity (serum, feces, gastric fluid, and implicated food)

Infant: culture from feces
Term
Clostridium botulinum treatment
Definition
respiratory support
antitoxin (equine >1y/o, human <1y/o)

wound only: penicillin metronidazole to follow antitoxin
Term
Clostridium botulinum prevention
Definition
heat food >60*
avoid honey for infants, breast feeding can be protective
proper wound care
Term
Clostridium tentani biology
Definition
large, G+ bacilli, spore forming, strict anaerobes, neurotoxin, motile, round terminal spores (tennis racket)
Term
Clostridium tentani virulence factors
Definition
spore formation
tetanolysin (oxygen-labile hemolysin)
tetanospasmin - heat-labile, AB toxin, B binds motor neurons, A is Zn-dependent endopeptidase
Term
Clostridium tentani pathogeneis
Definition
Tetanus: spastic paralysis; infection of spores in wound; incubate 1-21days, usually <8days; anaerobic causes germination, vegatative bacteria produce tetanospasmin, travels to blood, binds motor nerve endings, travels to CNS, blocks release of GABA, unregualted spastic activity; binds irreversibly, long recovery

Generalized: most common, trismus, risus sardinocus, body-wide spasms, opisthotonos, can progress to autonomic nerves

Localized: spasms at 1* infection site, indicates partial immunity or is the prodrome of generalized

Cephalic: head is 1* infection site

Neonatal: 1* infection at umbilical cord, becomes generalized, >90% mortality from apnea or sepsis
Term
Clostridium tentani epidemiology
Definition
rare in U.S., developing countries more prevalent
30-50% mortality
Term
Clostridium tentani diagnosis
Definition
clinical presentation, history of wound or prior vaccination
Term
Clostridium tentani treatment
Definition
debride 1* wound
passive immunization (TIG)
metronidazole
vaccinate with tetanus toxoid
supportive therapy until recovery
Term
Clostridium tentani prevention
Definition
vaccine: DTAP, 5 childhood, booster/10yr
prophilaxis: depends on vaccine hisotry
educate: about hygiene for cutting and cleaning umbilical cord
Term
Corynebacterium diphtheriae biology
Definition
G+ rod, nonmotile, aerobic, normal flora on skin, irregular club-shapted, "chinese leters", short chain myocolic acids in wall
Term
Corynebacterium diphtheriae virulence factors
Definition
diphtheria toxin - AB toxin, encoded on phage (lysogenic conversion), produced at site, travels in blood, targets heart and nerve cells
A - ADP-ribosylation enzyme, shuts down protein synthesis, host cell death
Term
Corynebacterium diphtheriae pathogenesis
Definition
Respiratory: 2-4 day incubate; sudden onset of malaise, low fever, sore throat, exudative pharyngitis (thick pseudomembrane that is adherent); systemic complications include myocarditis (1-2weeks) or neurophathy (10-30days) at oculomotor and ciliary nerves

Cutaneous: asymptomatic on carrier, trans by direct contact; papule --> pustule --> nonhealing ulcer that may have grayish membrane; co-infection with G+ cocci usually
Term
Corynebacterium diphtheriae epidemiology
Definition
Respiratory: poor urban areas around world, seen in elderly
Cutaneous: homeless, alcoholics, poor areas, reservations
Term
Corynebacterium diphtheriae diagnosis
Definition
clincal findings: start intial treatment
Grow on tellurite medium -> black colonies
toxin production (immunoassay, PCR tox gene)
takes a long time for confirmation
Term
Corynebacterium diphtheriae treatment
Definition
Respiratory: keep airway open, antitoxin from CDC

Cutaneous and resp: penicillin, macrolide, tetracycline
after recover, immunize with toxoid
Term
Corynebacterium diphtheriae prevention
Definition
DTaP vaccine
prophylaxis of close contacts
isolate respiratory pts
contact precautions with cutaneous pts
Term
Bordetella pertussis biology
Definition
G- coccobacillus, strict anaerobe, very small, nonmotile
Term
Bordetella pertussis virulence factors
Definition
tracheal cytotoxin (TCT) - disacch tetrapeptide like PG, binds and kills epithelial cells, induces IL-1 and fever
pertussis toxin (PT) - AB5 toxin, ribosylates G-protein, cAMP increase, increase mucus secretion
hemolysin - increases cAMP directly, inhibits chemotaxis and phagocytosis by PMNs
adhesins (ciliated brochial epithelial), filamentous hemagglutinin, pertactin, fibriae
Type III secretion (proctects against host)
Term
Bordetella pertussis pathogenesis
Definition
disease: Whooping cough
entry: respiratory
incubate: 7-10days
Catarrhal stage - 1-2weeks, resembles common cold, most contagious, highest load
Paroxysmal: 1-6 weeks, ciliated cells dying, mucus clearance impaired, deep violent coughing followed by inspiratory whoop and possible vomiting
Convalescent: paroxysms diminish in # and severity, secondary complications still possible (pneumonia)
Term
Bordetella pertussis epidemiology
Definition
endemic worldwide
pretty common, rising incidence in U.S. due to incomplete vaccine regemine
Term
Bordetella pertussis diagnosis
Definition
PCR (culture)
Term
Bordetella pertussis treatment
Definition
supportive b/c recognized after peak load
macrolides if severe
Term
Bordetella pertussis prevention
Definition
DTaP vaccine
prophylaxis to close contacts to reduce carriage
Term
Bacillus antracis biology
Definition
G+ bacillus, pairs or long chains, large, spore-forming, aerobic, nonmotile, nonhemolytic, grow rapidly in culture
Term
Bacillus antracis virulence factors
Definition
Capsule - poly-D-glutamic acid, invasive
Toxins (EF/PA or LF/PA)
Edema factor - adenylate cyclase, increases [cAMP], hypersecretion, edema in tissues
Lethal factor - Zn-dependent endopeptidase, induces apoptosis, necrosis of cells, tissue damage
Protective antigen - binding component, combines with and delivers EF or LF
Term
Bacillus antracis pathogenesis
Definition
Inhalation: spores in, move to LRT, multiply in lymph nodes; incubate 1-7days; initally flu-like, later worse pulm (necrosis, hemorrhage, effusion), elargemetn of lymph nodes, meningitis (50%), high fever, shock; die in 3 days w/o tx

Cutaneous: spores in cut, painless pustule surrounded by vesicles, regional lymphadenopathy, black/painless eschar with massive edema; 20% die w/o tx, rare with tx

GI: enter oral route; incubate 2-5days; abdominal pain, messenteric lymphadenopathy, nausea, vomit, diarrhea, GI necrosis, ulcer of mouth/throat, progresses to sepsis and shock; mortality 100% w/in few days
Term
Bacillus antracis epidemiology
Definition
Inhalation: rare in U.S., bio-terrorism organism, wool-sorters

Cutaneous: 95% of natural cases of this microbe

GI: very rare, herbivores
Term
Bacillus antracis diagnosis
Definition
microscopy/culture: grows fast to high numbers, motile, hemolytic
PCR - new, faster
Term
Bacillus antracis treatment
Definition
1st line: penicillin, doxycyline, ciprofloxacin
combo with other antibiotics
Term
Bacillus antracis prevention
Definition
Vaccine: for animals, humans in military and handling imported animal products
prophylaxis for 60days if exposed
Term
Bacillus cereus biology
Definition
G+ bacillus, large, spore-forming, aerobic, hemolytic, transient colonize skin
Term
Bacillus cereus virulence factors
Definition
heat-stable and heat-labile toxins
Term
Bacillus cereus pathogenesis
Definition
Emetic food: ingest contaminated rice; spores survive cook, germinate during cooling, produce toxins; incubate 30min-6hrs, heat-stable enterotoxin inudces nauesea, vomiting, abdominal cramps; duration 8-12 hours

Diarrheal Food: ingest contaminated meat, vegetables, sauces; spores survive cooking, germinate in gut; incubation 9-18hrs; heat-labile toxin acts like cholera toxin, induces [cAMP] causing water diarrhea, duration 20-36 hrs
Term
Bacillus cereus treatment
Definition
supportive no antibiotics
severe: vancomycin or clindamycin
Term
Bacillus cereus prevention
Definition
proper food handling and storage
Term
Pseudomonas aeruginosa biology
Definition
G- rod, aerobic, non-fermentative, oxidase+, fluorescein pigments: pyocyanin and pyoverdin, sweet culture odor; forms clear colony on MacConkey
Term
Pseudomonas aeruginosa virulence factors
Definition
multi-drug resistant, simple growth requirements, versatile
pilus, flagella
ETA - inhibits protein synthesis
S and T exoenzymes - cytotoxic, manipulate actin rearrangment, secreted by T3SS
elastase, protease, hemolysins, pyocyanin, pyoverdin, quorum sensing, capsule, biofilm
Term
Pseudomonas aeruginosa pathogenesis
Definition
Normal hosts: foliculitis, otitis externa, eye infections, endocarditis (IV drug users), pneumonia (ventilator, high mortality), UTIs, IV-line sepsis

Abnormal hosts:
Chronic colonization: pulmonary infection; increased mucus secretion from CF pts, long-term infection; loses pili, flagella and O antigesn, upregulates biofilm w/ quorom sensing; loss of lung function from inflammatory destruction

Invasive mode: malignant otitis externa (diabetics)

Systemic infection: ecthyma gangrenosum, hemorrhagic lesions on skin due to elastase production
Term
Pseudomonas aeruginosa epidemiology
Definition
Oppportunistic: antibiotic treatment, foreign body, VAP, IMC, burn pts, CF pts

Chronic - cystic fibrosis
Invasive - diabetes mellitus
Systemic - neutropenic, burn pts, pneumonia, and CF pts
Term
Pseudomonas aeruginosa diagnosis
Definition
green pigmentation of culture
fruit odor
oxidase+
clear growth on MacConkey
Term
Pseudomonas aeruginosa treatment
Definition
aminoglycoside + anti-pseudomonas B-lactam
Term
Pseudomonas aeruginosa prevention
Definition
avoid broad spectrum antibiotics in general
prevent contamination of sterile objects
Term
Escherichia coli biology
Definition
G- rod, oxidase-
Term
Escherichia coli virulence factors
Definition
O antigen, H antigen, K/Vi antigen, endotoxin, capsule, antigenic phase variation, T3SS, antibiotic resistance plasmids
Term
Escherichia coli pathogenesis
Definition
UTI: normal flora of GI travel up to kidney, uropathogenic E coli more virulent (P pili and HlyA)

Neonatal: 2nd most common cause of meningitis, K-1 capsular antigen strain, not normal flora but found in pregger GI, high mortality

Bacteremia and sepsis
Term
Escherichia coli epidemiology
Definition
UTI - women, newly married, elderly, urinary catheters
Term
Escherichia coli diagnosis
Definition
UTI - gram stain, oxidase test (-)

Neonatal - ultrasound, showing brain abnormality
Term
Escherichia coli treatment
Definition
UTI - trimethoprim
Term
Escherichia coli prevention
Definition
UTI - cleaning urethral meatus, cranberries, blueberries
Term
Enteropathogenic E. coli (EPEC) virulence factors
Definition
T3SS, intimin, Tir, pili
Term
Enteropathogenic E. coli (EPEC) pathogenesis
Definition
loose attachment by pili, pestal formation induced by T3SS: injects Tir which is expressed by host then and is receptor for intimin adhesin on bacterium

attaches to epithelial cells of small intestine, destroys microvilli, cause watery diarrhea, incubates 2-6days, acute onset, lasts 1-3 weeks
Term
Enteropathogenic E. coli (EPEC) epidemiology
Definition
developing countries, esp. infant diarrhea
Term
Enteropathogenic E. coli (EPEC) diagnosis
Definition
lactose fermentation, green sheen on EMB agar, culture, serotype, probe for exotocins
Term
Enteropathogenic E. coli (EPEC) treatment
Definition
treat symptoms
disseminated: fluoroquinolone and susceptibility testing
Term
Enterotoxigenic E. coli (ETEC) virulence factors
Definition
high ID(50);
heat-labile (LT-I and LT-II) - like cholera, increases cAMP -> increase solute secretion
heat-stable (STa and STb) - cGMP mediated fluid secretion
Term
Enterotoxigenic E. coli (ETEC) pathogenesis
Definition
1-2 day incubation
diarrhea for 3-4 days
Term
Enterotoxigenic E. coli (ETEC) epidemiology
Definition
developing coutries, traveler's diarrhea, feces-contaminated food or water
Term
Enterotoxigenic E. coli (ETEC) diagnosis
Definition
lactose fermenation, green sheen on EMB agar, culture, serotype, probe for exotoxins
Term
Enterotoxigenic E. coli (ETEC) treatment
Definition
treat symptoms
disseminated: fluoroquinolones and susceptibility testing
Term
Enterohermorrhagic E. coli (EHEC, STEC, VTEC) virulence factors
Definition
low ID(50), shiga-like verotoxin
Stx1 - binds to 28S rRNA, destroys intestinal villi,
Stx2 - targets and destroys endothelial cells
Term
Enterohermorrhagic E. coli (EHEC, STEC, VTEC) pathogenesis
Definition
Hermorrhagic colitis: incubate: 3-4 days; watery diarrhea with abdominal pain, vomit (50%), after 2 days, bloody diarrhea, intense ab pain, no fever; requires hospitaliztion, resolves ~1wk

HUS: shiga-toxin enters systemic circulation; acute renal failure, hemolytic anemia, thrmobocytopenia; 5-10 days after dairrhea onset
Term
Enterohermorrhagic E. coli (EHEC, STEC, VTEC) epidemiology
Definition
developed countires
"hamburger disease", unpasteurized milk, fruit juice, uncooked vegetables, fruits
Term
Enterohermorrhagic E. coli (EHEC, STEC, VTEC) diagnosis
Definition
MacConkey agar with sorbitol, serology O157 antigen, stool containing Shiga-like toxin
Term
Enterohermorrhagic E. coli (EHEC, STEC, VTEC) treatment
Definition
supportive, monitor for HUS

no antibiotics b/c would increase toxin release
Term
Enteroinvasive E. coli (EIEC) virulence factors
Definition
pInv genes - for invasion of colonic epithelium
Term
Enteroinvasive E. coli (EIEC) pathogenesis
Definition
2-3day incubation, water diarrhea to dysentery-like syndrome (mucoid, bloody diarrhea, cramps, fever), lasts 1-2wks
Term
Enteroinvasive E. coli (EIEC) epidemiology
Definition
rare in US, uncommon in developing countries
Term
Enteroinvasive E. coli (EIEC) diagnosis
Definition
lactose fermentation, green sheen on EMB agar, culture, serotype, probe for exotoxins
Term
Enteroinvasive E. coli (EIEC) treatment
Definition
treat symptoms
disseminated: fluoroquinolone and susceptibility testing
Term
Enteroaggregative E. coli (EAEC) virulence factors
Definition
bundle-forming fimbriae causes autoagglutination
Term
Enteroaggregative E. coli (EAEC) pathogenesis
Definition
persistent watery diarrhea
causes dehydration and growth retardation in children
Term
Enteroaggregative E. coli (EAEC) epidemiology
Definition
developing countries
Term
Enteroaggregative E. coli (EAEC) diagnosis
Definition
lactose fermentation, green sheen on EMB agar, culture, serotype, probe for exotoxins
Term
Enteroaggregative E. coli (EAEC) treatment
Definition
treat symptoms
disseminated: fluoroquinolones and susceptibility testing
Term
Shigella dysenteriae biology
Definition
G- rod, oxdiase-, faculative anaerobe, non-lactose fermentor, nonmotile, low ID(50)
Term
Shigella dysenteriae virulence factors
Definition
invasion plasmid
IpaD - recognizes receptors on enterocytes
IpaA and IpaB - promotes invasion
T3SS - injects IpaA and IpaB
IL-1b - secreted by infected cells, attracts PMNs and leukocytes
Shiga toxin - inhibits protein synthesis by cleaving 28S rRNA
Term
Shigella dysenteriae pathogenesis
Definition
Trans: fecal-oral (contaminated salads, like potato, shrimp, chicken, tuna), raw veggies, dairy products, meat, water, food handlers
incubate: 1-7dyas
small volume diarrhea, mild abdominal discomfort to full-blown dysentery (cramps, fever, diarrhea, vomit, blood, pus or mucous in stools), mucosal ulceration, rectal bleeding dehydration
Term
Shigella dysenteriae epidemiology
Definition
daycare outbreaks, children
Term
Shigella dysenteriae diagnosis
Definition
fecal leukocytes, culture stool
Term
Shigella dysenteriae treatment
Definition
FQ and guided susceptibility
Term
Salmonella enteritidis biology
Definition
G- rod, oxidase-, motile, non-lactose fermentors, high ID(50)
Term
Salmonella enteritidis virulence factors
Definition
T3SS - SPI-1 and SPI-2, resistance to acid (ATR gene)
Term
Salmonella enteritidis pathogenesis
Definition
Trans: contaminated poultry, eggs, water or contact with contaminated pet;
target: infection limited to lumen of intestine
incubate: 18-36hrs
symps: abdominal pain, diarrhea, fever, headache, chil, self-limiting in few days
Term
Salmonella enteritidis epidemiology
Definition
major cause of gastroenteritis
3rd most common food-poisoning agent
in elderly and infants, can be life-threatening
Term
Salmonella enteritidis treatment
Definition
no antibiotics, might prolong disease
Term
Salmonella typhi biology
Definition
G- rod, oxidase-, motile, non-lactose fermentors
Term
Salmonella typhi virulence factor
Definition
TS3 - SPI-1 and SPI-2, resistant to acid (ATR gene), low ID(50), replication/spread in macrophages, persistent in gallbladder
Term
Salmonella typhi pathogenesis
Definition
trans: fecal-oral, contaminated food or water, person-to-person
Typhoid fever: severe systemic, sustained fever and abdominal symptoms
1st week - rising, stepwise fever, bacteremia
2nd week - abdomen pain and rose spot rash on abdomen and trunk
3rd week - hepatomegaly, splenomegaly, intestinal bleeding
Term
Salmonella typhi epidemiology
Definition
developing countries
Term
Salmonella typhi diagnosis
Definition
culture from blood or marrow
Term
Salmonella typhi treatment
Definition
FQ or chloramphenicol
Term
Salmonella typhi prevention
Definition
vaccines: capsule or live
Term
Klebsiella pneumoniiae biology
Definition
G- rod, oxidase negative, nonmotile, ferments lactose, normal flora in GI and URT 5%
Term
Klebsiella pneumoniiae virulence factors
Definition
prominent capsule with mucoid appearance
Term
Klebsiella pneumoniiae pathogenesis
Definition
common cuase of community acquired primary lobar pneumonia
thick bloody sputum with currant-jelly appearance
Term
Klebsiella pneumoniiae epidemiology
Definition
alcoholics with compromised pulmonary function
Term
Klebsiella pneumoniiae treatment
Definition
cephalosporins
Term
Enterobacter biology
Definition
G- rod, oxidase negative
Term
Enterobacter virulence factor
Definition
ESBL - expended spectrum beta-lactamases
effective against 3rd generation beta-lactams
Term
Enterobacter pathogenesis
Definition
UTI in patients with urinary catheters

Bacteremia in ICU
Term
Enterobacter epidemiology
Definition
urinary catheters and ICU
Term
Serratia biology
Definition
G- rod, oxidase-
Term
Serratia pathogenesis
Definition
nosocomial pneumonia
Term
Proteus biology
Definition
G- rod, oxiase-
Term
Proteus pathogenesis
Definition
nosocomial and community-acquired pylonephritis and cytitis
kideny stones
Term
Proteus diagnosis
Definition
swarming motility
powerful urease activity
Term
Yersinia enterocolitica biology
Definition
G- rod, faculatative anaerobic, siderophilic
Term
Yersinia enterocolitica virulence factors
Definition
grows at 4* C
Yop proteins - encoded on plasmids, injected via T3SS, prevent phagocytosis, induces apoptosis of macrophages, suppresses cytokine production
Term
Yersinia enterocolitica pathogenesis
Definition
Gastroenteritis with contaminated foods

Blood-transfusion related bateremia
Term
Yersinia pestis biology
Definition
G- rods, facultative anaerobes, siderophilic, zoonotic
Term
Yersinia pestis virulence factors
Definition
Yop proteins - encoded on plasmids, injected via T3SS, prevent phagocytosis, induces apoptosis of macrophages, suppresses cytokine production
Capsule, plasminogen activating protease (rapid spread), serum resistant factor
Term
Yersinia pestis pathogenesis
Definition
Urban plague, Black Death, Sylvatic plague
Trans: aerosol, fleas are host, rodents are reservoir

Bubonic plague: incubate 7 days; sudden onset of fever, chills, weakness, headache, painful bulbo in groin/axilla, bacteremia, subepidrual hemorrhages, necrosis of extremities; 75% fatality

Pneumonic plague: 2* from bubonic or 1* from inhalation; rapid progressive necrotic pneumonia, highly infectious, 90% fatality
Term
Yersinia pestis epidemiology
Definition
Category A bioterrorism agent
Term
Yersinia pestis diagnosis
Definition
Suspicion when: fever and painful lymphadenopathy, traveled to endemic area, contact with vector
Culture and bipolar staining

RPT: F1 antigen detection, high specificity and sensitivity
Term
Yersinia pestis treatment
Definition
streptomycin or tetracyline
respiratory isolation (until pneumonia is ruled out, 48 hrs of therapy, and sputum culture is negative)
Term
Bacteroides fragilis biology
Definition
G- rod, strict anaerobic, endogenous (normal flora)
Term
Bacteroides fragilis virulence factors
Definition
capsule
B. fragilis toxin
extracellular enzymes
Term
Bacteroides fragilis pathogenesis
Definition
Abdominal abscesses and bacteremia
Wound exudates have strong, foul-smelling discharge due to organic acid production
Term
Bacteroides fragilis diagnosis
Definition
growth in 20% bile
collect and transport in oxygen-free environment
Term
Bacteroides fragilis treatment
Definition
Metronidazole + surgery + antibiotics for G- aerobic infection if mixed

resistant to kanamycin, vancomycin and colistin
Term
Peptostreptococcus biology
Definition
G+ cocci, strict anaerobe, endogenous to mouth, GI tract and genital tract
Term
Peptostreptococcus pathogenesis
Definition
wound infections, aspiration pneumonia, lung abscesses, brain abscesses, chronic otitis media, OBGYN infections
Term
Actinomyces israellii biology
Definition
G+ rod, strict anaerobe, filamentous, not acid fast
Term
Actinomyces israellii pathogenesis
Definition
colonize URT and GI tracts
Chonic granulmatous lesions: become supprative and form abscesses connected by sinus tract

Cervicofacial abscesses: patients with poor oral hygine or recent invasive dental procedure
Term
Actinomyces israellii diagnosis
Definition
sulfur granules: macroscopic colonies like grains of sand
Term
Actinomyces israellii treatment
Definition
penicillin + surgical intervention
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