Term
|
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
|
|
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
|
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
|
Definition
|
|
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
|
|
Term
| Escherichia coli prevention |
|
Definition
| UTI - cleaning urethral meatus, cranberries, blueberries |
|
|
Term
| Enteropathogenic E. coli (EPEC) virulence factors |
|
Definition
|
|
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
|
|
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
|
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
|
|
Term
| Salmonella typhi diagnosis |
|
Definition
| culture from blood or marrow |
|
|
Term
| Salmonella typhi treatment |
|
Definition
|
|
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
|
|
Term
|
Definition
|
|
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
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
nosocomial and community-acquired pylonephritis and cytitis
kideny stones |
|
|
Term
|
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
|
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 |
|
|
