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bordetella parapertussis

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bordetella parapertussis

  • less severe whooping cough in children with a shorter duration

  • brownish discoloration on media

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b. bronchiseptica

  • opportunistic pathogen for pneumonia and wound infections

  • kennel cough in dogs (vaccine required)

  • milder symptoms, grows on MAC

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b. pertussis/parapertussis transmission

  • aerosols (bacteria adhere/grow on ciliated resp epi cells

  • highly contagious: 90% exposed contract disease; adults can be transient carriers

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b. pertussis/parapertussis virulence factors

  • FHA: attach to epi cells

  • pertussis toxin (PT): inc cAMP = inc resp secretions/mucus

  • adenylate cyclase toxin: inc cAMP, inhibits chemotaxis, phagocytosis

  • tracheal cytotoxin: ciliostasis (cilia cannot clear airway)

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whooping cough

  • 1-2wks incubation period

  • catarrhal: flu like, sneezing, runny nose 1-2 wks; highly contagious

  • paroxysmal: sudden, severe cough followed by whoop

    • inc lymphs (looks like viral or leukemia)

  • in kids: cyanosis, very serious, need help breathing

  • convalescent: 4 wks after symptoms; dec coughing but can be wks-mos before recovery

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what specimen is needed for whooping cough dx?

  • nasopharyngeal: aspirate of fluid

    • calcium alginate or dacron swabs as deep as possible

      • cotton oils toxic to bordetella

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how to culture bordetella?

  • bordet gengou: potato infusion + glycerol + sheep blood

  • regan lowe agar: charcoal with 10% horse blood, cephalexin

  • also BAP, MAC, CHOC (r/o haemophilus)

  • incubate 35C, no CO2, 7 days, adequate moisture with gauze

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morphology of b. pertussis

  • GN rods/ccb

  • bordet gengou: small, domes, glistening (bisected pearls) often beta

  • regan lowe: smooth, silver, pinpoint (mercury droplets)

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  • b. pertussis: used for confirmation; requires larger amt of organism for agglutiantion test

  • francisella: safer

  • legionella: can cross react with p. aeruginosa

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how to treat b. pertussis

  • 1 month: erthryomycin, clarithromycin, azithromycin

  • <1 month: azithromycin (erythro assoc with infantile hypertrophic pyloric stenosis)

  • STX alternative for > 2months

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brucellosis (undulant fever)

  • reoccurring fever at regular intervals for days/mos/yrs

  • fever at night that goes away during day

  • wt loss

  • acquired from livestock contact (unpasteurized milk)

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transmission of brucella

  • undercooked meat, unpasteurized/raw milk

  • breathing in bacteria (dust, droplets) (lab workers)

  • thru skin wounds/abrasions/mucous membranes

    • slaughterhouse, meat packing, veterinarians

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b. melitensis

  • goats/sheep

  • most common isolate

  • severe disease, acute suppurative, granulomatous lesions

  • thionin and fuchsin

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b. abortus

  • cattle

  • mild sporadic disease, chronic granulomas in RE system organs

  • causes infectious abortions in cattle (bang’s disease)

  • fuchsin, H2S, capno

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b. canis

  • dogs

  • similar disease to b. abortus

  • thionin

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b. suis

  • pigs

  • destructive suppurative lesions; prolonged disease with granulomas mimicking TB

  • H2S, thionin

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specimens for brucella isolation

  • RES predilection = bone/BM

  • sterile BFs and urine also possible

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brucella characteristics

  • strict aerobes (some capno)

  • slow grower (21 days); brucella blood agar

  • non spore forming, w GN ccb (extend safranin stain time)

  • non motile, no capsule, intracellular

  • agent of bioterrorism = work in BSC

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brucella biochemicals

  • ox pos, cat pos

  • H2S and urease help speciate

  • submit acute/convalescent sera for sero testing

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where is francisella found?

  • wild animals: rabbits, muskrats, beavers

    • outbreaks lead to lots of deaths of these animals

  • ground water

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francisella transmission

  • zoonotic: tick/deer fly = primary vector

    • skin contact, ingestion/inhalation of contam water, dust, aerosols

    • hunters: handling carcasses, bitten, aerosols

    • mowing lawn

  • lab workers at risk

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rabbit fever = francisella

  • acute febrile, granulomatous disease with rapid onset and flu like symptoms

  • 5 presentations depending on site of infection:

    • ulceroglandular

    • glandular

    • oculoglandular

    • oropharyngeal

    • pneumonic

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francisella growth characteristics

  • facultative intracellular

  • non motile, small GN ccb

  • strict aerobe

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lab dx - francisella

  • culture not recommended

    • Lcystine, animal serum, egg yolk

    • cystine BAP

    • slow grow CHOC, no MAC growth

    • cystine heart dextrose = clear, pearlescent, convex, drop like colonies

      • sub to BCYE to keep alive

  • DFA, IHC, PCR, serology

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pasteurella srouce

URT and GI tract of mammals/birds (dog/cat scratches/bites OR inhaled)

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pasteurella diseases

  • local: cellulitis, abscesses, osteomyelitis, septic arthritis

  • resp: URTIs, pneumonia, tracheobronchitis, lung abscesses

  • cardiovascular: endocarditis, bacteremia, sepsis

  • CNS: rare meningitis (licks/bites to face in old ppl)

  • GI, ocular, UTIs

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p. multocida growth characteristics

  • GN pleomorphic ccb with bipolar staining (oval, short rods, longer filaments)

  • BAP, CHOC, no MAC

    • small gamma, mucoid, narrow green/brown halo

    • musty, mushroom, dog’s breath odor

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p. multocida biochemicals

  • ox pos, cat pos

  • nonmotile

  • weak acid from glucose ferm

  • pos indole, ODC

  • lack of rxns leads to misID on automated systems

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klebsiella granulomatis

  • endemic in tropical/developing countries (rare US)

  • causes donovanosis: uncircumcised men with poor hygiene, spread via sexual contact, can spread to bone/liver, assoc w pregnancy/cervical infection

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  • firm papule or subcut nodule that ulcerates at primary site of inoculation (genital area); swells lymphs nodes with lesions on skin above)

  • ulcerogranulomatous: hard, red, bleeds easily

  • hypertrophic or verrucous ulcer: dry, irregular edge

  • deep ulcer: necrotic, foul smelling

  • dry, sclerotic, cicatricial lesion: scarring

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donovanosis dx

  • no cultures

  • based on pt hx and disease presentation

    • confirmed with donovan bodies (intracellular) on tissue smears in macros, occ encapsulated

  • PCR not FDA approved

  • IFA thru ref labs

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  • normal oropharyngeal flora (some in humans, some in dogs/cats)

  • not speciated in lab

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capnocytophaga diseases

  • more septicemia than endocarditis (pts with neutropenia)

  • juvenile periodontal disease

  • fulminant, life threatening disease following dog/cat bite

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growth characteristics of capnocytophaga

  • GN rod fusiform (resembles fusobacterium (anaerobe))

  • facultatively anaerobic

  • CO2, BAP, CHOC after 2 days, no MAC growth

  • TM or ML agar (resistant to antimicrobials in these plates)

  • gliding motility on agar (like swarming)

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capnocytophaga biochemicals

  • negative for most

  • motile

  • pos nitrate, esculin

  • ferm: glu, mal, lac, suc

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legionella spp

  • intracellular parasite: enter and multiply within host cells (bronchoalveolar macros)

  • predisposed in:

    • immuno comp, chronic lung disease, alcoholics, heavy smokers

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how to contract legionnaires’ disease

  • inhalation of aerosols (not person to person)

  • sporadic - community acquired

  • epidemic: AC, cooling towers, fountains, windshield washers

  • nosocomial in IC: resp equipment, nebulizers, humidifiers, spas, ice machines

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legionnaires’ disease

  • range from asymptomatic to deadly

  • 2-10 day incubation

  • nonproductive cough, fever, headache, myalgia, bloody/purulent sputum, rales, difficultly breathing, shaking chills

  • dissemination to kidneys, heart, liver, CNS, lymphatics

    • damage to organs = death

  • mortality 15-30% sometimes 50%

  • most are serogroup 1

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pontiac fever

  • 2 day incubation

  • flu like symptoms: fever, headache, myalgia 2-5 days

  • spontaneous recovery, milder form, low mortality

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reservoirs of legionella

  • lakes, rivers, springs, man made water treatment systems (chlorinated water okay)

  • heating/cooling towers of buildings; fountains

  • can live at 20-43C up to 60C

  • adheres to pipes, rubber, plastics

  • intracellularly in protozoa

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specimen collection for legionella

  • resp: BAL, sputum, bronchial washings

  • urine for Ag test

    • found in urine for serogroup 1; stays pos for long time

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legionella lab ID

  • direct examination: pleomorphic thin w GNRs inside macros/neutros and extracellularly

  • urine Ag test

  • DFA test

  • check serotypes or DNA detection

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how to culture legionella

  • aerobically, requires L cysteine (no primary media)

  • BCYE: small pinpoint colonies

    • acid wash to remove normal flora

  • biplate: cystine/without cysteine (growth only on one side)

  • 35-37C 7 days; gray white or blue green convex, wet looking, will fluoresce

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how to treat legionella

  • erythromycin (alone or with rifampin)

  • alt: doxy, STX, new macrolides, fluoroquinolones

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streptobacillus moniliformis diseases

  • rat bite fever: bite/scratch from infected animal

  • haverhill fever: ingestion of contam material

  • abrupt onset fever, chills, headache, myalgia

  • maculopapular, petechial, pustular rash in extremities

  • joint swelling/pain

  • can progress to endocarditis, myocarditis, meningitis, pneumonia, sepsis

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s. moniliformis lab ID

  • specimen: primary lesion, lymph node, blood, joint fluid, pus

  • pleomorphic GNR; bulbous string of pearls/L shapes with age

  • enrich media with whole blood, serum, ascitic fluid

    • SPS in blood cx inhibits

    • gray, smooth, glistening, fried egg with L phase

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spirillum minus

  • rat bite fever (sodoku)

  • fever, ulcer, swelling, lymphadenopathy, rash on palms/soles, headache, vomiting

  • GN spiral rods with 2-3 coils, motile, stain with wright giemsa

  • cannot be cultures (dx on symptoms/microscopy)

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b. henselae

  • cat flea = cat scratch disease

  • fever, lymphadenopathy, papule/pustule at infection site

  • eye infections, severe muscle pain, encephalitis

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b. quintana

  • body louse = trench fever

  • fever (recurrent), headache, rash, bone pain in shins/neck/back

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b. bacilliformis

  • sand fly = carrions disease in western south america

  • oroya fever: fever, headache, myalgia, abd pain, severe anemia

  • verruga peruana: peruvian warts; nodular lesions under skin that emerge, ulcerate, bleed

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complications with bartonella

  • bacillary angiomatosis (BA): henselae, quintana

  • bacillary peliosis: henselae

    • lesions in skin, subcut tissue, bone, liver, spleen

    • HIV/IC

  • SBE: does not show up in culture

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growth characteristics of bartonella

  • cx from skin, lesion biopsy, occ blood

  • standard media but takes weeks to grow

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dx of bartonella

  • CSD: symptoms, hx, sero, PCR

  • trench fever: blood cx, sero

  • carrions: blood cx, blood smears in acute phase (oroya)

  • endocarditis: sero, PCR, cx heart tissue

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