246173104 Microbiology Step 1 Weird Exceptions and Detail

7/25/2019 246173104 Microbiology Step 1 Weird Exceptions and Detail

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Microbiology Step 1 weirdexceptions and forgotten detail

Introduction Prokaryotes: have a nucleoid instead of a nucleus

Mycoplasma has cholesterol in membrane and no peptidoglycan

o Cant gram stain it and beta-lactams dont work !so use

macrolides"o Cholesterol needed to grow it

#ungi have ergosterol except PCP ! therefore need to use $MP%SM&

trimethoprim% sulfamethoxa'ole "o PCP visuali'ed by S()*+, S$(.

Polycistronic /. only bacteria and viruses

o 0ne m,. carry many proteins !have multiple S(.+/+)2,.0 se3uences"

Sterile organs (detection any organism= pathological)

o Blood

o CSFo Stomach

Candida is normally present in the mouth4 when decreased immune

it over grows and causes oral thrush 5reast fed only6 bi7dobacterium ! 556 breastfed baby"

Pathogenicity ntigenic *ariation

o .8gonorrhea pili

o $rypanosome brucie !frican sleeping sickness"

o +nterobacteriaceae: capsular and 9agellar antigen

o (* : antigenic drift of gp1;

(g protease : Si.

Strep pyogenes M protein 6 degrade C


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o $ cell independent antigen

o Causes release of cytokines ()-1 ()-= $.#-alpha

o )eads to S+PS(S !septic shock"

o > works the same mechanism as superantigenfrom

Straph aureus and strep pyogenes 6 high cytokines

they activate many C/? $ cells 6 polyclonalactivation $ cellssun"urn rash and in#ol#es palms and soles

+xotoxins Protein synthesis

o +# /P ribosylation!stops translation": C8dipthernia4

Pseudomonas aueriginosao @S of the =;S ribosome : Shigella4 ++C

.eurotoxin: by inhibit release .$

o C8tetani: prevent release glycine and 25

o C8botulinum: prevent release ch

Superantigen: staph aureus and strep pyogenes

CAP : cholera4 anthrax4 +coli +$+C4 Pertusis

o CA: work via 2s

o P works via 2i

Cytolysins: !LP$! %O&I'

o Clostridium perfringens: lecithinase 6 2S gangrene

o Straph aureus: cell membrane leaky

5acteria

Structure Cell wall protect from osmotic damage !peptidoglycan"

o $herefore penicillin will break this down

Capsule protects !only remo#ed "y OPSI'I!%IO'"

o 5acillus anthracis made from polyglutamate can activate $

cell Spores: bacillus and clostridium

o /iplicolinic acid4 calcium dipicolinate 4 keratin

o Spores are made in the stationary phase when

birth6death

2rowth on medias $hioglycolate : anerobes B cant breath air : clostridium4

bacterioides4 actinomyces Chocolate agar

o .eisseria ! $hayer-Martin4 *.P : vancomycin4 colistin4

nystatin"


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o aemophilus in9uen'a8 > also grows S!%LLI% colony

with Staph aureus .eed vactors & and * ! protoporphyrin and ./"

!typical pneumonia ( all don*t stain +ith gram)

o ,ycoplasma pneumonia = gro+s ,!LB-./ colony on

sterol agaro Legionella: gro+s on cysteine and irono Chlamydia : intracellular

0xygen special nerobes: Bcant breath air 6 clostridium8 5acteroides4

actinomycin 0bligate aerobes: mycobacterium4 .ocardia4 and pseudomonas

aeruginosa4 bacillus Microaerophil: campylobacter and elicobacter

o %hey +ill say 0SPCI!L I'C-B!%O.Stains

cid fast : cryptosporidium

2omoris methamine silver stain 6 PCP

uramine rhodamine 9uorescent dye: $5

/ont stain with 2,M18 Mycobacteria due to waxy cell wall8 Spirochetes thin


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1ram Positi#e cocci Strep agalactiae : C!,P testE (ppucrate

Staph aureus

o Coagulase forms abscess bc 7brinogen7brin

/ersinia other +ho has coagulase

o Scalded skin syndrome : epidermis peal !exfoliative toxin".ikolski E

o /raining sinus from osteomyelitis predispose to

s3uamous cell cancero CF$+ +./0C,/($(S !(2 fever4 fatigue4 murmer"

Su"acute: splinter hemorrhage2 osler nodes2

roth spots2 +eighloss2 night s+eatso $reatment

18 .afcillin and oxacillin8 M,S: vancomycin


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$etanus Spores germinate in tissues

$reatment if symptomatic or no vaccine6 Ig 3

metronida4ole(anaero"e) 3 dia4epam for spasm $etanus prone

o (f didnt get primary vaccination or unknown: vaccine E (go (f had vaccine : give vaccine if booster was J years ago

Perfringens Stormy fermentation for milk E double 'one hemolysis

Crepitus

)P toxin% phospholipase C 6 lecithinase

(dentify on 11 /OL5 agar

yperbaric chamber after debridement and clindamycin bc its

anerobic therefore die from high 0/iKcile

utoclave things to kill spores

(f rxn need

18 Stop antibiotic8 2ive metronida'ole


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o $uberculin :surface protein E mycolic cause PP/

one of induration 6 M+.S +&P0S+/ !not diseased"

o Jmm : (* or recent exposure

o 1J mm : normal people

Mycobacteria leprae:

$uberculoid 6 )epromin E test4 granuloma4 $h14 little acid fast )eptromatous: test -4 $h4 many acid fast

1ram 'egati#e#acultative intracell

)egionella

#rancisella - granulomatous

5rucella- granulomatous

,ifampin prophylactic exposure .8meningitisis

emophilus

0xidase positive !all enterobacteriacea negative for oxidase" .eisseria

Pseudomonas

elicobacter

Campylobacter

Frease E BPF.C-proteus-urea plasma- nocardia

-cryptococcus-h8pylori

Spontaneous peritonitis : C$,O%$.!P/ P!%I'%S ( theepithelium damaged) enter in cause peritonitis ( alsonephrotic)

-5acteriodes fragillis-+8coli

Bacteria.eisseria meningitides

Fsually associated with /(C bc only gram negative to ,+)+S+

)PS since it over produces it *accine only !HIC" .0$ 5 which is J;N of meningitis in FS bc

capsule nonimunogenic2onorrhea

2ram negative diplococci (.$,C+))F),

S+P$(C arthritis in sexually active young O.++

Causes ophthalmia like chlamydia

o Chlamydia also has P.+FM0.(


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Pseudomonas aeruginosa (n respirators4 in 9owers and water4 and raw vegetables therefore

not allowed in burn units )(*+, P,(M,H $,2+$ ! /iptheria was < and nerves with same

toxin"

Capsule Coloni'e eschar in burn victim

'eutropenia2burn patient4 and C2/

)egionella Pool boy4 air conditioner4 fountains

Pathy in7ltrate 6 atypical pneumonia

/iagnose: /# ! direct 9uorescent antibody"

Silver stain4 and CH+%5CH+ ! buQer charcoal yeast extract6

cysteine and iron""#rancisella tularensis

$ick bite or traumatic6 ulceroglandular 6 ulcer and regional

lymph Pneumonia if inhaled

Serology diagnose ! .+*+, CF)$F,+4 )S0 5,FC+)) ./

H+,S(.("5rucella

Fnpasteuri'ed dairy !1O!%S ,IL5"

S!%I'1 !' $P!%O,1!LL/ ( leptospira other

hepatomegaly) Chronic: P.SSIO' 3 s+eating

5ordetella pertussis

Fnvaccinated !immigrant4 Rehovahs4 religious" ave 7lamentous hemagglutinin

Camp by inhibit 2i

lso tracheal cytotoxin: interfere with cilia ! therefore need to

cough hard to get it up"o Ihooping cough6 paroxysmal cough ending with

gasp!whoop"o ,epetitive cough with 2SP at end4 and may vomit

Causes hypoglycemia

Campylobacter DeDuni Curved4 microaerophile4 oxidase E !like elicobacter"

2rows at ? degrees

Polar 9agella !gulls wings"

2uillain barre! 0:1 serotype" and ,eiter

*ibrio cholera 6 a lot of 9uid loss .ingers lactategive them 6 replenish the OE and C0


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nter"o"acteriaceae18 ll ferment glucose8 .itratesnitrites;7 Catalase 3


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18 $yphi 6 $HP0(/ #+*+,@ ne#er cause of gastroenteritis or osteomyelitis

only "t+ humans

Li#es in macrophages "c pre#ent fusion phago and

lysosome li8e %B

Concentrated in gall "ladder +here "ileconcentrated ( therefore resistant to "ile)

Ieek 1 in blood4 rose coloured spots

Ieek < in stool

C0.S$(P$(0. more common than diahrea

8 0thers: typhimurium4 enteritidis Iidal test: antibodies to antigen 044 *i

Chickens and reptile pets

0steomyelitis in sickle cell ! kid played with turtle"

aemophilus in9uen'a $ype b capsule ! polyri"itol phosphate"

< month- years not vaccinated

o meningitis

o epiglottitis !thumb print on lateral &ray"

o pneumonia

> still cause otitis media E sinusitis by nontypable !but strep penumoG1"

C+O endocarditis subacute- aemophilus aphrophilus- ctinobacillus actinomycetemcomitans

- Cardiobacterium homonis- +ikenella corrodens : FM. 5($+S- Oingella kingae: FM. 5($+S

$reponema PallidumPrimary Painless chancre !open sore" /ark 7eld

#luorescentmicroscopy

Secondary

,ash macuopapular diQuse includesoles and palms

-condyloma lata : 9at

1" Serology : */,)sensitive !b to

cardiolipin""Speci7c: #$-5S

$ertiary 2ummas!granulomas"ortitisC.S$abes dorsalisrgyll ,oberston pupil B

0nly #$-5S


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accommodate but dont reactCongenital

Still birth/eaf4 notched teeth4 rash4 sabershin! new bone on periosteum"

Rarisch-erxheimer rxn: increase temp4 decrease 5P4 rigors4leukopenia

)yme disease !Blyme on #C+6 facial palsy4 arthralgia4 cardiac4erythemia migrans"Stage 1 $arget rash ! hyperemic concentric rash" Muscle and Doint pain4 headache4 fatigue4 fever and

chills !9u like"< 5ell palsey !bilateral"4 arrhythmia4 arthritis immune

complex4 meningitis

Chlamydia ,ickettsia Mycoplasma0bligate intracellular 0bligate .o.o $P .o $P .ormal $P

,odiAedpeptidoglycan(lac8s muramic)

.ormal .o peptidoglycan hascholesterol instead

Chlamydia penumoniae:!%$.OSCL.OSIS

!typical pneumonia >9 ( after mycoplasma)

Intracytoplasmic inclusionsiseases

Chlamydia trachomatis

o Causes conDunctivitis and atypical pneumonia in neonate

o Staccato cough: inspiration btw each cough

o .eed erythromycin drops after birth into eye !.8gonorrhea

also causes conDunctivitis but .0 P.+FM0.( )isteria can cause SP0.$.+0FS abortions4 or infant

granulomas all over

)ymphogranuloma venereum : chlamydia )1-)

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246173104 Microbiology Step 1 Weird Exceptions and Detail