Microbio Flashcards
Gram nonreactive bacteria
Chlamydia
Legionella
Acid fast bacteria
Mycobacteria
Nocardia
Indicates mycolic acid in cell wall
Gram stain and shock
LPS on Gram negative most likely to cause shock
But gram + can also cause through various virulence factors
Protein A
Expressed on S aureus
Binds i gg to subvert immune response
Diphtheria toxin
Interferes with protein elongation at EF 2
Shiga toxin
Inhibit proteinsynthesis by damaging ribosomes
LPS
Complementactivation via tlr4 cd14 MD2 → cytokine release and widespread immune response
DIC
LPS → clotting factors and platelet migration
Waterhouse friderichsen syndrome
Adrenal failure in setting of septicemia often +DIC
Usually neisseria meningitis
Also pseudomonas, ‘s pneum, s aureus, H flu
Organ failure
Adrenocorticalinsufficieny
Severe hypotension
Coma
Toxic shock
Associated with superantigens that cause cytokine storm
SEB, TSST1, SEC2, strep exotoxin a and c
Skin desquamation
Usually s_pyogenes or Saureus
Toxic component LPs
Lipid A
C perfringens
Gas gangrene
S aureus lab tests
Positive:
Gram
Catalase
* CoagulaSe
* DNase
* Mannitol ferment
Other:
* B-hemolytic
Novobiocin sensitive
Bile salt resistant
- unique from other staph species
Test differentiating S epi from S. Sapro
Novobiocin
Epi - sensitive
Sap - resistant
S epidermis
Norm(al skin ‘
Endogenous infections in ic., venous line, foley,
→ cellulitis osteomyelitis endocarditis UTIs -
Medical devicecontamination.
Mainly subacute endocarditiswhen history of value replacement acute more likely aureus
S saprophyticus
Vaginal flora
Gu infections in sexually active young women
Strep tests
Glram POS
* catalase Ng
* Pairs or chains
Non motile
No spores ‘
Hemolysis differentiates spectes
- differentiates staph
S. Agalactiae tests
Group B strep
B hemolytic
Bacitracin resistant
S.pyogenes tests
Group A strep
B-hemolytic
Bacitracin serisitive
Pyr rapid test
Anti-streptolysin o (aso) titers
Anti-dnase B, anti hyaluronidase,anti streptokinase,anti-m
S. Pneumonia e tests
Alpha hemolytic
Optochin sensitive
Encapsulated
Viridans strep tests
’ Opportunistic
No cap:sule
Alpha hemolytic
Optochin resistant
Group B strep infections
Normal vagina
Infection in Newborns after vag delivery
Septicemia, meningitis, pneumonia,osteomyelitis
S. Pneum infection s
Normal upper respiratory
Meningitis, otitis media, pneumonia, sepsis
Especially severe in kids, old, ic, asplenic
Group A strep infections
Aka pyogenes - fever
N normal skin and throat
Strep throat
Skin infections
Necrotizing fasciitis
Autoimmune sequelae due to m protein
M protein
- Group a strep (pyogenes)
Blocks complement
*Rheumatic fever
Post infectious glomerulonephritis
Spe-b
Superantigen
Protease precursor
S pyo → necrotizing fasciitis
Rheumatic fever
Type 2 hypersens
M protein
2-3 weeksafter strep throat. Not group A strep skin infections for some reason
2 major or 1 major 2 minor:
M: polyarthritis, carditis,nodules, erythema, chorea
m: fever, arthralgia w/o polyarthritis, high CRP or ESR, prolonged PR interval on EKG
Post strepglomerulonephritis
Type 3 Hs
Skin or pharyngeal GAS
Dx w/ elevated ASO or anti-dnase B
Viridian’S strep infections
Dental caries
Subacute endcaarditis on previously damaged valves
Opportunistic
Biofilms
CAP tx outpatient
Presumptive for S. Pneumoniae unless other risk factors
Generally a macrolide (-thromycin)
Can be fluoroquinolone (-floxacin), doxy
Pneumococcal pneumonia tx inpatient
IV 3rd gen cep + macrolide (-thromycin)
Eg. Ceftriaxone+ azithromycin
+ Vanco if complicated eg. HAP VAP
Pneumococcal meningitis tx
Vanco + cef-3
Outpatient tx uncomplicated strep
Amoxicillin
Erythromycin if allergy
B cereus
Bacillus
Gram POS
Spore forming i
Contaminated food
Reheated fried rice prototypical
B cereus tx
Supportive
Most cases dt toxins and most bacteria are abx-resistant, so ab x not generally given
Inhalation anthrax
Hemorrhagic mediastinitis - widening of mediastinum on X-ray
Necrotizing pneumoni a
Bacteremia
Meningitis
Fatal
B anthracis tx
- Combination clindamycin and linezolid for inhalation
Ciprofloxacin or doxy for localized cutaneous
Gas gangrene
C. Perfringens
Alpha toxin - perforates cells
Listeria monocytogenes
Vulnerable-neonates, pregnant, ic, old
Contaminated food e.g. Unpasteurized dairy raw veg processed meat
Vertical trans..
In healthy adults visuallyself-limited gastroenteritis
Listeria pregnancy and neonates
Early pregnant: sa, stilbirth,prematurity
After birth meningitis, septicemia
Listeria Ab x
Resistan t to most
Most notablyfluoroquindones
Ampicillin preferred
Growing resistance
Bact rim usually works
Cold enrichment
Largely unique to listeria
Accelerated growth at cooler temps
Common feature in all nocardia i infections
Abcess
Nocardia pneumonia
Ic. or preexisting lung disease
Necrosis, cavitations, abscess
Secondarydissemination causing abscesses in brain, skin
Can also cause primary abscesses elsewhere
Nocardiaappearance
Gram positive rods in chains or filaments
Similar toactinomyces but weakly acid-fast
Nocardia eco niche
Soil
Obligate O 2
Nocardia tx
Slow growing ‘’
Prolonged ab x course
No resistance yet
Poor px when disseminated
Bactrim is tx of choice
HUS
Shige-like toxin in ehec
Microthrombi shear red cellsand platelets
Anemia-thrombocytopenia - acute kidney failure following bloodydiarrhea
Shiga-like to mins
Inhibit 28 S on 60 s ribosome subunit
Also independently necrosis and inflammation
Ehec
Neonatal meningitis
Most commonly E coli
Also listeria
Pil i
- Biofilms,epithelialedherenu
Kleibsellapreumonia
. Vulnerable pts
Diabetes, etoh
Pulmonaryhemmorahgic necrosis
Red currant jelly sputum
Aspiration prenmonia
Macconkey agar
Lactose fermentation turns media pink
Eg. Ecoli lactase POS → pink
Pseudomonas aeruginosa
Ic, vulnerable - cf, burns, leukemia, age s neutropenia
Hap/ VAP
Non-respiratory e.g. Hot tub folliculitis, otitis external, osteomyelitis following penetrating injury, UTIs from catheters, necrotizingenterocolitis in leukemia
Pseudomonas tx
4th gen ceph + amino glycoside (-mycin)
Pip/tazo mosaggrssive
Salmonella tests
Motile facultative ‘ anaerobe
ferments glucose
Reduces sulfer- black t si medium
Shigella infectious dose
Very low
Resistant togastric acid
Shigella tx
Ceftriaxoneand fluoroquin clones
Salmonella tx
Supportive
Ab x prolonginfectious duration
Y ersinia enterocolitica
.galstroenteritis / food poisoning from pork products, puppies
Iron overloadpredisposes
Pain can mimic appendicitis
Y-entero tx
Supportive if uncomplicated
Otherwise aminoglycosydes (my cin) and bact rim
Tend to be fluoroquinoloneresistant
Campylobacter jejune appearance
Motile curved or corkscrew gram neg rod
Campy virulence
Direct invasion of intestinalepthelium
Corkscrew shape and flagellum
→ bloody diarrhea
Can result in reactivearthritis
Campy transmission
Under cooked chicken most common
Campy complications
Reactive arthritis
Guillan barre
Urease
Involved in H pylori, y enter o, some other enter bacterium
NeutralizesStomach acid via ammonia production to promote survival
Whooping cough toxin
Pertussis exotoxin binds ‘ G, protein receptor increasing secretions
Pili paralyze mucocilary escalator
Pertussis complications
Respiratoryexhaustion
Pertussis encephalopathy
Pertussis tx
Macrolides (-thromycin)
Prophylaxis with erythromy in for contacts
Tdap prevention
Legionella path
Enter and replicate in alveolarmacrophages
Type 4 secretion system effector proteins
Legionnaire’s sx
Neuro-headache, confusion
Diarrhea
Lobar or atypical pneumonia
Often hyponatremia
Generally all together
Legionella tx
Azithromycin or levofloxacin
Neisseriameningitidis manifestations
Meningitis
Purpuri c rash
Possible URI
Complications:
Di c
Waterhous-friderichsen syndrome
Neisseria tx
Ceftriaxone
H flu manifestations
Meningitis
Epiglottitis
Pneumonic
Otitis media
Esp in 6-18 mo between breastfeadingand vaccination
Acinetobacter
VAP
Lyme disease st
Stage 1: Erythema migran s / bull’s eye
Stage 2:
Facial nerve palsy
Arthritis
Cardiac block
Stage 3:
If untreated
Meningitis
Rocky mountair spotted fever
Dog tick
Southeastern us
Headache -fever- rash on palms and solesof feet
Leukopenia
Hyponatremja
Hepatic transaminase
Thrombocytopenia
RMSF tx
Doxycydine
Yersinia pestis
Rat fleas
Bacteria invade mq
Tender, swollen lymph nodes
Lesion at bite site
Progression to septicemic plague - DIC + necrosis
Yersiniapestis tx
Streptomycin
Q fever
Coxiella burnetii
Farm animals
Flu-like
Pneumonia
Endocarditis with’negative cultures (C. Burn doesn’t culture well)
Hepatitis
Ssdna virus
Parvoviridae is only currently clinically relevant
All other DNA viruses are ds
Ds DNA viruses
Adenovirus
Papillomavivus
Polyomavirus
Hepadnavirus - hep B
Herpesvirus
Poxvirus
Parvovirus b 19
Naked icosahedral ss DNA
Infects immature erythrocytes
Kids: fifth disease - slapped cheek rash
Sickle cell: aplastic crisis
In u tero: hydropsfetalis
Adults: arthritis
Adenorinus
Naked icosahedral ds DNA linear
Conjunctivitis,pharyngitis, ge, myocarditis, acute hemorrhagic cystitis
HPV
Naked icosahedral ds DNA circular genome
1 and 2: warts
6 and 11 - genital warts
16 and 18-cervical cancer
CMV
Herpesvirus
Enveloped icosahedral ds DNA
R eactivation infection in ic - pneumonia, esophagitis, retinitis, colitis
Mono (2nd most common to ebv)
Congenital: retinitis, microcepholy, hearing loss, seizures, blueberry muffin rash
Roseola
HHV 6 and 7
High fever x few days → macular rash
Kaposi sarcoma
Opportunistic
Triggered by hhv8 in ic
Circular DNA genomes
Hepraviridae- hep B
Pappllomaviridae
Polyomaviridae
Blueberry muffin rash
Congenital CMV - congenital rubella
Indicates extramedullary hematopoesis
CMV in HIV
AIDS if outside liver spleen or lymph nodes
Prolonged, progressive
Retinitis → hemorrhage → blindness
Colonic ulceration
Pneumo nitis
Encephalitis
CMV in transplant
Primary from organ or secondary from reactivation
Higher rejection risk
Fever
Pneumonia
Hepatitis
Pancreatitis
Colitis
CMV blood smear
Owl eye inclusion body
Reactive lymphocytes
CMV tests
CMV lg M or G
High WBC
High lfts
Negative eb V monospot
CMV tx
Gangliocivir prophylaxis in HIV W CD 4 <50, organ transplant, hsct
Potentially Gangliocivir, valganciclovir, foscarnet, cidoforvir in severe infection Es pecially newborns
Mono
Most commonly eb v in young otherwise healthy
Posterior cervical and submandibular lymphadenopathy
Fever
Hepatosplenomegaly
Exudative pharyngitis
Fatigue
If hepatosplenomegaly avoid contactsports for 12 monthsdue torisk of rupture
St usuallyresolve2-3 wk
Fatigue longer
Starry skylymiph node
Burkitt lymphoma
Eb v associated
Myc gene
Owl eye cells
Hodgkin lymphoma - aka Reed sternberg - eb v associated
CMV infection
Oral hairy leukoplakia
White patches on tongue in ic
Eb v associated
Eb v test s
Monospot
Eb v early antigen ig G for 6 mo
Anti- eb Na after that
High WBC
High lfts
EBV tx w amoxicillin
→ diffusemacropapular rash
Can develop to erythema multiform e (target)
Chickenpox tx
Acyclovir first 24 hours or if complicated
Symptomatic eg r. Antihistamines
VSV antibodies, IV acyclovir can be used if very complicated e.g. In pregnant women orhiv
Post herpetic neuralgia tx
Capsaicin, gabapentin, TCAs, steroids
Postherpetic neuralgia
A complication after shingles rash has cleared
Dt sensory Herve damage
Ds RNA viruses
Reoviridal is only clinically relevant genus i
Includes rotavirus and Colorado tick virus
Orthomyoxviridae
(-)ssRNA
Along withretroviruses the onlythat replicates in nucleus
Includes flu
F protein
Membrane fusion protein in RSV
Influenza complications
Primary pneumonia
Secondarybacterial pneumonia
Cns- encephalitis, meningitis,guillan barre
Other- myositis, rhabdo. Myocarditis,pericarditis
Neuraminidase
Cleaves sialic acid residues to allow for viralspread/release from host cell
Flu
Measlescomplications
Diarrhea
Giant cell pneumonia
Encephalitis
Subacute sclerosing panencephalitis 7-10 years post infection → death
Mumps complications
Pancreatitis,orchids (testes), meningitis, encephalitis, myocarditis, nephritis
Rubella presentation
Rash start face down body spare palms soles
Generalizedeymphadenopathy ( unlike measles)
Low grade fever vs high grade in measles
Rubellacomplicatins
Arthritis
Encephalitis,
Guillanbarre
Idiopathicthrombocytopenic purpor a
Myocarditis
Congenitalrubella - torch infection,life threatening- blueberry muffin rash
Congenital rubella
IUGR - small size
Blueberry muffin rash
Bi lateral cataracts
Sensorineuralheaving loss
Machine heart murmur- patent da, VSD
Intellectual disability
Opportunistic pneumonia in HIV
Pjiroveci - PCP
Cocci
Tb
Dimorphic fungi
Mold in cold
Yeast in heats
C. Albicans dimorphism
Exception
Yeast in cold
Mold in heat
Amphoterrible side fx
Fever, and chills
HypOkalemia
Dt perforation of renal tubular ducts
Cytokine gran uloma
TNF a
Folic acid synthesis inhibitors
Trimethopri M
Sulfa drugs
Metronidazole
Targets DNA integrity
Bacterial andprotazoal
Rifampin
Targets mRNA synthesis
Fluoroquinotones
_Floxacin
Gyrase inhibitors
50 S inhibitors
Macrolide s- thromycin
Cindamycin
Linezolid
Chloramphenicol
30 s inhibitors
Aminoglycosides. - mycin/ micin except -thromycin; amikacin
Tetracyclines -cycline
Peptidoglycan synthesis inhibitors
Vancomycin
Bacitracin
Antipsendomonals
Piperacillin
Ticarcillin
Cefepime
Monobactams-azetronam
Carbapenems
Polymyxin if resistant
Daptomyan
Cell membranedisruption
Lipopeptide
Penicillins coverage
Gram POS
Especially syphilis and group B strep
Staph first line
Methicillin, nafcillin, oxacilion, aminopenicillins with beta lactamase inhibitors
Aminopenicillins coverage
Listeria
Strep pneumonia e
Staph
Enterococcus
Piperacillin coverage
E coli
Bacteroides
H flu
Staph aureus
Pseudomonas
Ceftaroline coverage
Fifth gen cef
MRSA
Gram POS and many neg
Aztreonam
Monobactam
Pseudomonas
E coli
Kleibsella
Carbapenems coverage
Pseudomonas
MRSA
Enterococci
Daptomycin coverage
MRSA
Enterococci
Fluoroquinolone’S coverage
E coli
Legionella
Salmonella typhi
Anthrax
Aminoglycosides coverage
- mycin _ micin - amikacin
Gram negative aerobes
Tetracyclines coverage
Chlamydia
Rickettsia
Lyme
Tigecycline coverage
Broad
E coli
Kleibsella
MRSA
Amphenicols
’ 50 S inhibitors
Cholera
S aureus
St pneumonia e
Rickettsia
E coli
Macrolide’S
- thromycin ‘
Strep
Staph
Legionella
Chlamydia
Linezolid
50 S inhibitor
Oxazolidinore
MRSA
Vancomycin-resistant enterococci (VRE)
Penicillin resistance gene
MecA
MRSA tx
Vancomycin
Daptomycin
Linezolid
Tigecycline
Ceftaroline
Doxycycline
Tmp-smx
Multi- drug resistant tx
Polymyxins
Carbapenems
Polymyxin
Binds phospholipids on cell surface.
A last resort
Penicillin resistance strep pneumonia
Changes in structure of target pbps
Unlike most other organisms which is beta lactamase production
Jarisch herxheimer rxn
Penicillin G reaction
Fever and chills
Low bp
Skinlesions
Beta lactams cause _ _ dependent killing while aminoglycosides are __ dependent.
- Beta lactams - time
Aminoglycosides-concentration
Gonorrhea tx
Ceftriaxone
Cephalosporins adverse effects
Less likely to cause Hs than penicillin but still avoid in penicillin allergy
Autoimmune hemolytic anemia
When w/aminoglycosides nephrotoxicity
When w/ alcohol disulfiram like reaction - flusing, hypotension, tachycardia, n+v
Vancomycin infusion reaction prophylaxis
Antihistamines and slow infusion
Mechanism vancomycin
InhibitNAG-NAM unit from being added to peptidogyan chain in cell wall
Cipro levo moxi differences
Cipro= systemic
Levo and moxi= respiratory, above diaphragm
Fluoroquinolones Mx
DNA gyrase/topoisom erase inhibitors
Fluoroquinolone resistance
Target sitealteration
Efflux pumps
Cipro uses.
Gram neg. rods:
- E coli, H flu, moraxella, kleibsella, legionella, *pseudomonas, salmonella, ‘s typhi anthrax
Some gram POS cocci
Tb
No:
Gonorrhea - resistance
Strep pneumonia
Systems:
Gi, gu, bone, joint, CNS
Levofloxacin uses
Similar coverage to cipro but
- better lung distribution
- S pneumonia coverage
- better MRSA
- better legionella
- worse atpseudomonas
Basically hap, cap and skin
Moxifloxacin uses
Similar tocipro but:
- not for UTIs
- better at mycoplasma including CNS Tb
- better gram POS bacilli
- worse pseudomonas
Mostly hap,CNS tb, complex abdominal
Also fine renal impairment
- vs adjust dose
Donot take fq with
Cations eg.calcium, iron
Adjust dose of p450
Adjust dose cipro and levo renal disease
C/i qt interval prolongation/ tor Sades de points.
C/i. Myasthenia graves dt peripheral nm j
Fluroquinolone side effects
Renal
Torsades de pointes /QT elongation
CNS, PNS
Allergy - relatively rare
Rash - photosensitivity
Sjs-rare
Avoid in kids - joints and cartilage
Sulfonamides target
Dihydropteroate synthase dhps
TMP target
Dihydrofolate reductase DHFR
Tmp-smx resistance
More PABA precursor
Enzyme alteration
Efflux pumps
Tmp.smx coverage
Aerobic
POS and neg
Nocardia
Fungi- p. Jiroveci
Protazoa-plasmodium
No:
Anaerobic
Intracellular
Mycoplasma
Mycobacteria
Spirochetes
Aminoglycoside adverse fx
Nephrotoxicity - acute tubular necrosis
Ototoxicity.
Vestibulotoxicity
C/i. Myastenia gravis-NMB
Monitor every 3 days
Macrolide AES
Gi - diarrhea at motil in recepto
Q t prolongation
Hepatotoxicity
Linezolid AES
Bone marrow suppression
Peripheralneuropathy
Serotoninsyndrome_ Mao cross reactivity
Second line Tb
Streptomycin
Amikacin
Cipro
Cycloserine- MDR
Paraaminosalizylic acid- MDR
Ethionamide
Component of mycobacterium cell wall
My colic acids
Acid fast stain
Synthesis targeted by isoniazid
Isoniazid vita min deficiency
B6
Acyclovir
Guanosine analog
Activated by herpes viral kinases
Specific to herpes viruses
Hsv- 1,2
VZV
Ganciclovir
Similar to acyclovir
CMV
Acyclovir -resistant HSV
Cidofovir
Viral DNApolymerase inhibitors
CMV retinitis in AIDS
Acyclovir resistant HSV
Foscarnet
Nonspecific viral polymerase inhibitor
RNA, DNA, rt
Herpesvirus, HIV
Ribavarin
A/G mimic
Induces mutation in RNA replication
Also vs:. DNA viruses
Hep C, severe RSV
Oseltamivir
Zanamivir
Flu neuraminidase
Release budding virus from cell
Within 48h of sx
HBV tx
Adefovir - adenosine analog rna-dept DNA poly inhibitor
Entecavir - DNA poly inhib
Lamivudine- cytosine analog, chain term, DNA poly and HIV rt
Telbivudine- thymidine analog, DNA poly and its rt activity
Tenofovir- DNA poly,HIV rt
Ifn.2a
Ns 5a inhibitors
HCV
MOA unclear
Daclatasvir
Ledipasvir
Ombitasvir
Ns 5b inhibitors
HCVreplication
- buvir
Ns 3/4 a protease inhibitors
HCV translation
- Previr and ritonavir
Eb v tx
Symptomati- acetaminophen and NSAIDs
Antivirals not helpful
Foscarnet Æ
Renal impairment
Electrolytes- low k, CA, mg
RSV t x
Supportive
Ribavarin if complex
Broad spectrum nucleoside antiviral
Purine mimic
Chain terminator
Viral RNA poly
Palivizumab for prevention
Ribararin AES
Anemia
Hemolytic anemia
Neutropenia
Anemia → MI in preexisting cv
Teratogen
-navir
HIV protease inhibitors
-gravir i
HIV integrase inhibitors
Maraviroc
HIV attachment inhibitor ccr5
Enfuvirtide
HIV penetration/entry inhibitor gp41
First line malaria
Chloroquine
Resistance common
Severe/complicated malaria tx
Iv quinine and doxy or clindamycin
Transition to Po quinidine
Mx:
- reduce 02 uptake
-Reduce carb metabolism
- intercalates into DNA
Malaria prophylaxis
Atovaquone- proguanil
Doxy
Mefloquine
Toxoplasmosis tx
Sulfadiazine
Pyrimethamine
Trypanosomiasis tx
Chagas- Latin America - cv
Beznidazole
Nifurtimox
Sleeping sickness - Africa- cns
Melarsoprol - cns
Pentamidine isethinonate _ blood
Roundworm and pinworm tx
Ivermectin
Tapeworm and hookworm t
Benzimidazoles
-Bendazole
Shistosomasis tx
Praziquantel
Fungal membrane target
Ergosterol
Fungal cell wall target
Beta glucan
Flucytosine
Nucleotide analog precursor
Antifungal - fungistatic
Thymidylate synthetase inhibitor