Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
61 Cards in this Set
- Front
- Back
|
Haemophilus Overview |
oxidase + catalase variable faculative anaerobe opt. growth in 5-7% CO2 norm. res. of upper respiratory tract |
|
|
species implicated as human pathogen |
H. influenzae H. parainfluenzae H. ducreyi H. aphrophilus |
|
|
Haemophilus influenzae virulence factors |
polysaccharide capsule iga proteases adherence factors outer membrane proteins and lipooligosaccharide |
|
|
Other H. flu disease |
~otitis media and acute bronchitis (cause by nontypable strains) ~conjuctivitis ~aegyptius is associated w/ brazilian purpuric fever
|
|
|
H. flu id |
~requires 5-10 CO2 ~no growth on SBA but may satellite around other organism ~Chocolate: small, smooth, flat, tan, translucent at 24 hours ~requires both x (hemin) and V (NAD) to grow ~porphyrin test neg (cant use ALA to synthesize porphyrins) ~indole pos is presumptive (though neg. result doesn't rule it out
|
|
|
H. flu susceptibility |
test and report beta lactamase report AM, CRO, and IPM Set sensi on all CSF or blood isolates or if requested |
|
|
H. flu treatment |
treat w/ choramphenicol or 3rd gen ceph. amp resistance is common |
|
|
H. ducreyi clinical sig |
STD causes chancroid genital ulcers |
|
|
H. ducreyi id |
extremely fastidious specimen must be processed quickly direct GS may display school of fish morp |
|
|
H. parainfluenze id |
only V factor required |
|
|
HACEK Organisms |
A. aphrophilus A. actinomycetemcomitans C. hominis E. corroden Kingella |
|
|
A. aphrophilus clin sig |
1. normal flora of upper respiratory tract 2.endocarditis and brain abscess are common 3. pneumonia, meningitis and secondary bacteremia less freq. |
|
|
A. aphrophilus gs and sba |
1. gs: may be filamentous 2. 48-72 hrs to discern morph 3. yellow, convex, granular 4. grade school paste odor |
|
|
A. aphrophilus id |
1. X and V: loses x req. upon subculture 2. porphyrin test is + 3.Oxidase, Catalase, Indole - 4. Nitrate and ONPG + |
|
|
A. actinomycetemcomitans clin sig |
1. normal oral flora 2. often associated w/ actinomycotic infections 3. SBE, bacteremia, wound and dental infections |
|
|
A.actin. gs |
~may for a distinctive star shape w/ 4-6 points after 48 hrs ~must be grown on clear agar and light microscope used |
|
|
A. actin id |
1. oxidase and indole - 2. catalase and nitrate + |
|
|
C. hominis clin sig |
normal upper respiratory flora disease is almost exclusively associated w/ SBE |
|
|
C. hominis gs |
may retain crystal violet at poles may be arranded in a rosette pattern |
|
|
C. hominis colony morph |
small glistening, opaque colonies |
|
|
C. hominis id |
1. catalase and nitrate - 2. oxidase and indole + |
|
|
Eikenella corroden clin sig |
1. normal oropharyngeal flora 2. may be involved in dental and perodontal infections 3. also ocular, head and neck infections 4. clenched fist injuries 5. pleuropulmonary infections brought on by aspiration pneumonia |
|
|
E. corrodens on choc. |
flat, dry, yellow, spreading, 50% pit agar, bleach like odor |
|
|
E. corrodens id |
1. catalase and indole - 2. oxidase and nitrate and orn + |
|
|
eikenella corrodens ast |
predictably susceptible to penicillin and amp |
|
|
K. kingae clin sig |
normal flora of genitourinary tract bacteremia, sbe, bone and joint infections (especially in children) poor oral hygiene and mucosal ulcerations contribute to entry of organism into blood stream |
|
|
kingella colonly morph |
soft b hemolysis may pit some can grow on mtm |
|
|
K. kingae id |
oxidase + catalase, nitrate and indole - *K. dentitrificans is + |
|
|
capnocytophaga species clin sig |
human strains normal to oropharyngeal flora implicated in localized juvenile peridontis sepsis in patients w/ underlying illnes canine strains associated w/ dog bites |
|
|
gabnocytophaga on bap |
yellow, tan or slightly pink colonies may have marginal finger like progections grows on mtm |
|
|
capno id |
oxidase and catalase - except for canine species nitrate variable indole- gliding motility |
|
|
Pasteurella Clin Sig. |
*high association w/ animal bights *focal soft tissue infections *also bacteremia and chronic respiratory infections *P. multocida is the most commonly recovered species |
|
|
P. multocida direct smear |
*small GNCB *May exhibit bipolar staining |
|
|
Pasteurella ID |
*SBA/Choc: convex, smooth, grey, nonhemolytic, rough and mucoid variants *MAC: no growth *Oxidase, indole, Catalase + |
|
|
Pasteurella Susceptibility |
*testing not standardized *perform and report B-lactamase *predictably susceptible to penicillin, amoxicillin and tetracycline *resistant to 1st generation cephs |
|
|
Streptobacillus noniliformis Clin sig |
*normally found in the oropharynx of rodents *causes "rat bite fever" *Haverhill fever may result from ingestion *possible complications include endocarditis, pneumonia, septicemia or brain abscess |
|
|
S. moniliformis ID |
*special culture methods necessary *inhibited by SPS, use citrate for blood and joint fluids *grows "puff balls" in broth *GS: filamentous forms *ID is problematic due to cultivation requirements *rapid id possible only w/ gas-liquid chrom. |
|
|
Bordetella sp characteristics |
*sm. GNCB *all are catalase + *strict aerobes *most are assacharolytic *B. pertussis is the most fastidious
|
|
|
Pathogenesis of B. pertussis |
*Whooping Cough *highly communicable disease affecting children *bacteria attach to respiratory cilia *toxin production paralyzes cilia and causes inflammations *ag allow evasion of host defenses |
|
|
Clinical features of Pertussis |
*catarrhal stage (symptoms similar to common cold) *paroxysmal phase (classic whoop and coughing spells) *Convalescent phase (coughing freq. and severity decreases) |
|
|
pertussis complications |
*pneumonia *seizures *encephalopathy *otitis media, anorexia, dehydration |
|
|
Pertussis vaccine |
*acellular vaccine *contains purified, inactivated components of bacterial cells *sig. more effective than the whole cell vaccine |
|
|
other Bordetella spp |
*B. parapertussis *B. bronchiseptica *may cause pertussis like symptoms (generally less severe) |
|
|
B. pertussis id |
*specimen of choice is a NP swab *transport media: Regan Lowe *Cultivation media: Bordet-gengou *incubation 35C in 5-7% CO2 for up to 7 days *2-4 days smooth, shiny, high domed, like mercury droplets |
|
|
Brucella ssp |
*facultative intracellular parasite *brucellosis: undulant fever *zoonotic: acquired from contaminated animals or animal products |
|
|
Brucella ssp |
*B. abortus (cattle) *B. melitensis, B. ovis (sheeps and goats *B. suis (pigs) *rarely B. canis (dogs) |
|
|
Transmission of Brucellosis |
*through abrasions of the skin from handling infected mammals *occurs more frequently by ingesting contaminated milk and dairy products *highly infectious in the lab via aerosolization |
|
|
Brucella clin features |
*incubation period of 2-3 wks *symptoms range from asymptomatic to serious debilitating disease *other complications may include arthritis and endocarditis |
|
|
Brucellosis risk groups |
meat inspectors animal handlers vets laboratorians |
|
|
Brucella spp id |
*specimen of choice is blood or bone marrow *GS: stain poorly as GNCB *strictly aerobic *non motile |
|
|
Brucella ID |
*Oxidase, catalase, urease, nitrate + *speciation accomplished by rapidity of urea hydrolysis, ability to produce H2S, req for CO2 and sus to the analine dyes |
|
|
Francisella tularensis clinical sig |
*etiologic agent of tularemia or "rabbit fever" *transmission contracted by direct cutaneous inoculation (ticks), inhalation
|
|
|
Clin features of tularemia |
*symptoms: fever, chills, headache, and generalized aches *distinct forms of infection: ulcerogladular, glandular, oropharyngeal, intestinal, pneumonic, typhoidal |
|
|
F. tularensis Id |
*Possible specimens for isolation include primary ulcers, lymph node aspirates or biopsies, sputum, bone marrow, liver/spleen biopsies *gs: small, pale staining *obligate aerobe *growth req: cysteine *growth choc, mtm (not on MAC) *nonmotile, oxidase - |
|
|
Legionella pneumophila clin sig |
*associated w/ surface and potable water *adheres to pipes, rubber and plastics *survives temps 40-60 *survives and multiplies in free living protozoa |
|
|
L. pneumophila transmission |
*most people are exposed few develop symptoms *exposure to aerosols of water *inhalation is primary route of infection
|
|
|
risk factors for acquiring legionaire's disease |
*cigarette smoking *diabetes mellitus *cancer *end stage renal disease *aids |
|
|
L. pneumophila clin features |
*cause 2-8% of all pneumonias *infections may be asymptomatic, nonpneumonic (pontiac fever--0% mortality) *pneumonic 15-30% |
|
|
Lab Methods for detection of legionella |
*culture (live bacterial cells) *fluorescent ab (staining bacterial ag) *DNA PCR (bacterial DNA) *clinical tests (urine ag, serology) |
|
|
L. pneumophila id |
*spec. order: BAL, sputum, bronch wash, lung biopsy *transport w/out holding media or saline but it can be refrigerated *No growth SBA *BCYE/SBCYE: hold for 5 days min |
|
|
L. pneumophila colony morph and testing id |
*mottled surface, iridescent sheen, or 'cut glass' appearance *suspect colonies are subbed to SBA *catalase, oxidase, and motility may all be weak *Hippurate + *DFA |
