Micro Flashcards
Capsule in B Anthracis
Poly D glutamate
Endotoxin mediates effects via
Lipid A activation of TNF, IL1, IL6
Outermembrane unique to
Gram -
Lipoteichoic acid unique to
Gram +
Lipoteichoic acid induces
TNF alpha and IL1
Staphhylococcus
Gram + coccus in clusters
Streptococcus
Gram + coccus in chains/pairs
Enterococcus
Gram + coccus in pairs or short chains
Bacillus
Gram + rod
Clostridium
Gram + rod
Corynebacterium
Gram + rod
Gardnerella
Gram variable rod
Lacobacillus
Gram + rod
Listeria
Gram + rod
Mycobacterium
Acid fast rod (gram+?)
Propionibacterium
Gram + rod
Actinomyces
Branching rod
Nocardia
Weakly acid fast branching/filamentous
Moraxella
Gram - coccus
Neisseria
Gram - coccus
Bacteroides
Gram - enteric rod
Campylobacter
Gram - enteric rod (comma)
Fusobacterium
Gram - enteric rod
Helicobacter
Gram - enteric rod
Klebsiella
Gram - enteric rod
Proteus
Gram - enteric rod
Pseudomonas
Gram - enteric rod
Salmonella
Gram - enteric rod
Serratia
Gram - enteric rod
Shigella
Gram - enteric rod
Vibrio
Gram - enteric rod
Yersinia
Gram - enteric rod
Bordetella
Gram - respiratory rod
Burkholderia
Gram - respiratory rod
Haemophilus
Gram - respiratory rod (pleomorphic)
Leigionella
Gram - respiratory rod (silver stain to see)
Bartonella
Gram - zoonotic rod
Brucella
Gram - zoonotic rod
Francisella
Gram - zoonotic rod
Pasteurella
Gram - zoonotic rod
Anaplasma
Gram - pleomorphic
Ehrlichia
Gram - pleomorphic
Chlamydiae
Gram - pleomorphic – giemsa stain
Rickettsiae
Gram - pleomorphic – giemsa stain
Mycoplasma
Gram - pleomorphic (membrane has sterols that do not gram stain)
Borrielia
Gram - spirochete (Giemsa)
Leptospira
Gram - spirochete
Treponema
Gram - spirochete
Bugs that don’t gram stain well
Treponema, Leptospira (too thin);
Mycobacteria (high lipid in cell wall);
Mycoplasma, Ureaplasma (no cell wall);
Legionella, Rickettsia, Chlamydia, Bartonella, Anaplasma, Ehrlichia (Primarily intracellular)
These Little Microbe May Unfortunately Lack Real Color But Are Everywhere
Giemsa stain bugs
Chlamydia, Borrelia, Rickettsia, Trypanosomes, Plasmodium
Certain Bugs Really Try my Patience
PAS bug
Tropheryma whipplei (Whipple disease)
Ziehl Neelson stain bugs
Acid-fast – Mycobacteria, Nocardia (stains mycolic acid in cell wall)
Cryptosporidium oocysts
India Ink (and alternative)
Cryptococcus neoformans, mucicarmine can also stain capsule
Silver stain
Coccioides, PCP, Legionella, H. Pylori
H Flu media
Chocolate – Factor V (NAD) and X (hematin)
N. Gonorrhoeae and meningitidis media
Thayer Martin – selectively inhibits gram + w/ Vanco and other gram - w/ TMP and Colistin and fungi w/ Nystatin
Very Typically Cultures Neisseria
B Pertussis media
Bordet-Gengou – potato extract
Regan-Lowe – Charcoal, blood, antibiotic
C. diptheriae media
Tellurite agar, Loffler medium
M tuberculosis media
Lowenstein-Jensen
M pneumoniae media
Eaton agar (req cholesterol)
MacConkey changes when…
Lactose fermenters produce acid –> pink
E Coli media
Eosin-methylene blue – turn green metallic
Legionella media
Charcoal yeast extract buffered with cysteine and iron
Fungi media
Sabouraud
Important aerobes
Nocardia, Pseudomonas, MycoBacterium tuberculosis
Nagging Pests Must Breath
Important anaerobes
Clostridium, Bacteroides, Fusobacterium, Actinomyces
anaerobes Can’t Breath Fresh Air
Abx ineffective against anaerobes
Aminoglycocides because require O2 to enter cell
Facultative anaerobes
Strep, staph, enteric gram +
Obligate intracellulars
Rickettsia, Chlamydia, Coxiella
stay inside when its Really CHilly and COld
Facultative intraceullars
Salmonella, Neisseria, Brucella, Mycobacterium, Listeria, Francisella, Legionella, Yersinia pestis
Some Nasty Bugs May Live FacultativeLY
Encapsulated bacteria
Pseudomonas, Strep pneumo, H. flu type B, Neisseria meningtidis, E. coli, Salmonella, Klebsiella, gb Strep
Please SHINE my SKiS
Capitalized in pneumococcal vacine (13-conjugate, 23-no conjugate), H flu (con. vaccine), Meningococcal vax (conjugate)
Urease pos
Proteus, Cryptococcus, H pylori, Ureaplasma, Nocardia, Klebsiella, Staph epi, Staph sapro
Pee CHUNKSS
Catalase pos
Nocardia, Pseudomonas, Listeria, Aspergillus, Candida, E coli, Staphylococci, Serratia, B cepacia, H pylori
Cats Need PLACESS to Belch their Hairballs
Protein A fxn and bug
Fxn: Binds Fc of IgG to prevent opsonization/phagocytosis
S. aureus
IgA protease fxn and bug
Cleaves IgA to allow colonization of mucous membranes
Strep pneumo, H flu type B, Neisseira (SHiN)
M protein fxn and bug
Prevents phagocytosis by molecular mimicry –> acute rheumatic fever
GAS
Type 3 secretion bugs
Gram - –> Pseudomonas, Salmonella, Shigella, E coli
Specialized transduction
group A strep erythrogenic toxin, Botulinum toxin, Cholera toxin, Diptheria toxin, Shiga toxin
ABCD’S
How staph becomes vanc resistant
Transposition of VanA gene from VRE
Core of spores have
Dipicolinic acid
Spore forming bacteria
Bacillus anthracis (anthrax), bacillus cereus (food poisoning), clostridium botulinum (botulism), clostridium difficile (pseudomembranous colitis), clostridium perfrengens (gas gangrene), clostridium tetani (tetanus)
BC
Exotoxins that inactivate EF 2
Diptheria toxin (c diptheriae) –> pharygitis w/ pseudomembranes and severe lymphadenopathy (bull neck)
and exotoxin A (pseudomonas) –> host cell death
Exotoxins that inactivate 60s
Shiga toxin (shigella) –> GI mucosal damage –> dysentery (also cytokine release –> HUS)
and shiga-like toxin (EHEC O157H7) –> cytokine release –> HUS) – doesn’t invade host cells
Exotoxins that cause increased cAMP
Heat labile toxin (ETEC) – overactivates AC –> increased cAMP –> increased Cl secretion and H2O efflux –>watery diarhhea
(Labile in the Air)
Edema toxin (b anthracis) – mimics AC to increase cAMP –> edema around eschar in cutaneous anthrax
Cholera toxin (vibrio cholera) – overactivates AC by permanently activating Gs –> increased Cl secretion/H2O efflux –> rice water diarrhea
Pertussis toxin (b pertussis) –> overactivates AC by permanently inactivating Gi –> impairs phagocytosis –> whooping cough
Exotoxins that cause increased cGMP
Heat stable toxin (ETEC) – overactivates GC –> incrased cGMP –> less NaCl/H2O reabsorption –> watery diarrhea
(Stable on the Ground)
Exotoxins that cleave SNARE
Tetanospasmi (c tetani) –> prevents release of inhibitory GABA in Renshaw cells –> spastic paralysis, risus sardonicus, and lockjaw
Botulinum toxin (c botulinum) –> prevents release of stimulatory ACh at NMJ –> flaccid paralysis/floppy baby
Exotoxins that degrade cell membranes
Alpha toxin (c perfringens) – phospholipase degrades cell membranes –> myonecrosis and hemolysis
Streptolysin O (s. pyogenes) -- degrades cell membranes --> RBC lysis (Basis for ASO abs)
Exotoxins that are superantigens
Toxic shock syndrome toxin (s. aureus) – binds to MHC II and TCR to cause release of IL1, IL2 IFN gamma, TNF alpha –> fever, rash, shock
Exotoxin A (s pyogenes) – same but also scarlet fever
Main effects of endotoxin
- Macrophage activation (TLR4) –> fever (IL1, IL6, TNF alpha), hypotension (TNF alpha, NO)
- Complement activation –> histamine release –> hypotension/edema (C3a, C5a), neutrophil chemotaxis (C5a)
- Tissue factor activation –> coagulation cascade –> DIC
Differentiate staph
- Cat positive (df from strep)
- Coag (pos – aureus) negV
- Novobiocin (sens – epi, resistant – sapro)
Differentiate strep
- Cat negative (df from staph)
- alpha hemolytic
optochin sens – pneumo, opto res – viridans
beta hemolytic
bacitracin sens – GAS, bacitracin res – GBS
gamma hemolytic
grows in 6.5% NaCl – Group D enterococcus
won’t grow in 6.5% NaCl – Strep bovis
Lactose fermenting bacteria
Turn MacConkeey’s pink
FAST: E coli, Klebsiella, enterobacter
SLOW: Serratia, citrobacter
EMB agar
Lactose fermenters turn purple/black except E coli which is green
False positive VRDLs
Viral infxns (EBV/hepatitis)
Drugs
Rheumatic fever
Lupus and leprosy
VRDL
Palm and soles rash
Coxsackie A (HFM)
RMSF
2o Syphillis
CARS
Tx of t cruzi
Benznidazole or nifurtimox
Tx of leismaniaiasis
Visceral: amphotericin
Cut.: Sodium stibogluconate
Tx of malaira
Chloroquine but lots of resistance (blocks plasmodium heme polymerase)
Primaquine
Mefloquine or atovaquone/proguanil for prevention/tx of resistant strains
IV Artesunate or quinidine for falciprum cerebral malaria
Tx of african sleeping sickness
Suramin for blood born (SERUM)
Melarsoprol for CNS penetration
Tx of toxo
Sulfadiazine and pyrimethamine
Inegested nematodes
Enterobius, Ascaris, Toxocara, Trichinella (Don’t EATT them)
Cutaneous nematodes
Strogyloides, Ancylostoma, Necator (Walking in the SANd)
Nematodes by bite
Loa loa, Onchocerca volvulus, Wucharia bancrofti
Lay LOW and don’t get bit
Weird nematode txs
Those that are in addition to bendazoles:
Enterobius vermicularis – pyrantel palmoate
Ancylostoma and necator – pyrantel palmoate
Strongyloides – ivermectin
Instead of bendazoles:
Onchocerca volvulus – ivermectin
Wucheria bancrofti – diethycarbamazine
Loa loa – diethylcarbamazine
Weird taenia soleum tx
Neurocysticercosis – albendazole
Billiary tract disease, cholangiocarcinoma
Clonorchis sinensis
Brain cysts, seizures
Taenia solium (neurocystocercosis)
Hematuria, squamous cell bladder cancer
Schistosoma haematobium
Liver (hyatid) cysts
Echinococcus granulosis
Microcytic anemia
Ancylostoma, necator
Myalgias, periorbital edema
Trichinella spiralis
Perianal pruritis
Enterobius vermicularis
Portal hypertension
Schistosoma mansoni, japonicum
Vit B12 def
Diphyllobothrium latum
Live attenuated vaccines
MMR, Yellowfever, Rotavirus, Influenza (intranasal), Chickenpox (VZV), Small pox, Sabin polio virus
Music and LYRICCS are best enjoyed LIVE
Killed vax
Rabies, Influenza (shot), Salk Polio vax, HAV (humoral immunity only – stable)
SalK=Killed
RIP Always
Subunit vax
HBV (HbsAg), HPV (6,11,16,18)
Only ssDNA virus
Parvo “part-of-a-virus”
Only circular DNA viruses
Papilloma, Polyoma, Hepadnavirus
+ RNA genome viruses
Retro Toga Flavi Corona Hepe Cali Picorna
“I went to a RETRO TOGA party where I drank FLAVORED CORONA and ate HIPPIE CALIFORNIA PICKLES”
Only dsRNA virus
Reo “Repeato”
Naked genome infectious
most dsDNA (not pox or HBV) and + ssRNA
Only DNA virus that replicates elsewhere
Pox in the cytoplasm
Only RNA virus that replicates elsewhere
Influenza and retroviruses
DNA viruses
Hepadna, Herpes, Adeno, Pox, Parvo, Papilloma, Polyoma
HHAPPPPy
Only non-icosahedral DNA virus
Pox (complex)
CMV receptor
Integrins (heparin sulfate)
EBV receptor
CD21
HIV receptors
CD4, CCR5, CXCR4
ParvoB19 receptors
P antigen on RBCs
Rabies receptors
Nicotinic AChR
Rhinovirus receptors
ICAM-1
Inclusions in HSV/VZV
Intranuclear eosinophilic Cowdry A bodies
Negative stranded viruses
Arenavirus, Bunyavirus, Paramyxovirus, Orthomyxovirus, Filovirus, Rhabdovirus
Always Bring Polymerase Or Fail Replication
Segmented viruses
Bunyavirus, Orthomyxovirus, Arenavirus, Reovirus
BOAR
Picornaviruses
Poliovirus, Echovirus, Rhinovirus, Coxsackievirus, HAV
PERCH
Picornavirus that cannot cause asepctic meningitis
HAV, rhinovirus
Genetic shift
Reassortment of viral genome segments w/ different strains (pandemics)
Genetic drift
Minor changes based on random mutation in HA or NA genes (epidemics)
CD4 <500 bugs
Candida thrust
EBV oral hairy leukoplakia
Bartonella henslae bacillary angiomatosis (neutrophilic inflam)
HHV8 Kaposi sarcoma (lymphocytic inflam)
HPV SCC, often of anus in MSM or cervix of women
CD4<200 bugs
DIsseminated histo
HIV dementia
JC virus reactivation –> PML
PCP pneumonia
CD4<100 bugs
Aspergillus systemic Candida esophagitis CMV retinitis, esophagitis, colitis, pneumonitis, encephalitis Cryptococcus meningitis Cryptosporidium diarrhea MAC -- TB like Toxo -- brain abcesses