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648 Cards in this Set

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teichoic acid is unique to what type of organisms?
gram-positive
endotoxin/LPS (outer membrane) is unique to what type of organisms?
gram-negative
what do teichoic acid and lipid A induce?
TNF and IL-1
space between the cytoplasmic membrane in gram-negative bacteria
periplasm - contains many hydrolytic enzymes, including beta lactamases
this mediates adherence to surfaces, especially foreign surfaces, e.g. indwelling catheters
glycocalyx - made of polysaccharide
this contains a variety of genes for antibiotic resistance, enzymes, and toxins
plasmid - made of DNA
what is the only gram-positive with endotoxin?
listeria
what is exotoxin made of?
polypeptide
what is endotoxin made of?
lipopolysaccharide
typical diseases with exotoxin?
tetanus, botulism, diphtheria
tpical diseases with endotoxin?
meningococcemia, sepsis by gram-negative rods
gram-negative cocci?
neisseria
these have a gram-negative cell wall but are too small to be seen with light microscope
spirochetes - must be visualized with darkfield microscope
no cell wall; neither gram-positive or gram-negative
mycoplasma
name the 6 classic gram-positives
strep
staph
bacillus
clostridium
corynebacterium
listeria
lipopolysaccharide found in cell wall of gram-negative bacteria
endotoxin - heat stable
this bug inactivates elongation factor (EF-2), causes pharyngitis and pseudomembrane in throat
corynebacterium diphtheriae
ADP ribosylation of G protein stimulates adenylyl cyclase, increasing pumping of Cl- and H20 into gut
cholera
what does e. coli heat-labile toxin stimulate?
adenylate cyclase
what does e. coli heat-stable toxin stimulate?
guanylate cyclase
what does bordatella pertussis stimulate?
adenylate cyclase; also inhibits chemokine receptor
double zone of hemolysis on blood agar?
C. perfringens
what does C. tetani block the release of?
inhibitory NT glycine
what does C. botulinum block the release of?
acetylcholine
what does shiga toxin do?
cleaves host cell rRNA; also enhances cytokine release, causing HUS
what type of bugs are rickettsia and chlamydia?
intracellular parasites
neisseria meningitidis ferments what?
maltose and glucose
neisseria gonorrhea ferments what?
glucose
what produces a blue-green pigment?
pseudomonas
what produces a red pigmetn?
serratia maracescens
IgA proteases allow what organisms to colonize mucosal surfaces?
strep pneumo, neisseria meningitidis, neisseria gonorrhoeae, h. flu
silver stain?
fungi, PCP, legionella
india ink?
cryptococcus neofromans
Ziehl-Neelsen stain?
acid-fast baceria
PAS stain?
stains glycogen, mucopolysaccharides; used to diagnose Whipple's disease
Giemsa's stain?
borrelia, Plasmodium, trypanosomes, chlamydia
congo red?
amyloid; apple-green birefringence in polarized light (because of beta-pleated sheets)
chocolate agar with factors V and X?
H. influenzae
Thayer-Martin (VCN) agar?
N. gonorrhoeae
Bordet-Gengou (potato) agar?
B. pertussis
tellurite plate, Loffler's medium, blood agar?
C. diphtheriae
Lowenstein-Jensen agar?
M. tuberculosis
pink colonies on MacConkey's agar?
lactose-fermenting enterics - Klebsiella, e. coli, enterobacter (fast); citrobacer, serratia (slow)
charcoal yeast agar buffered with increased iron and cysteine?
Legionella
Sabouraud's agar?
fungi
obligate aerobes (4)
Nagging Pests Must Breathe
nocardia, pseudomonas, mycobacterium TB, bacillus
obligate anaerobes (3)
clostridium, bacteriodes, actinomyces - lack catylase and/or superoxide dismutase, and thus are susceptible to oxidative damage; generally foul smelling, difficult to culture, and produce gas in tissue (CO2 and H2)
obligate intracellular bugs (2)
rickettsia, chlamydia (stay inside when it's Really Cold)
facultative intracellular (8)
Some Nasty Bugs May Live FacultativeLY:
salmonella, neisseria, brucella, mycobacterium, listeria, francisella, legionella, yersinia
encapsulated bugs (4)
strep pneumo, H. flu, neisseria meningitidis, klebsiella - positive quellung reaction
bacillus anthracis, c. perfringens, and c. tetani form what?
spores (gram positive soil bugs)
alpha hemolytic bacteria?
strep pneumo (catalase negative and optochin sensitive)
viridans strep (catalase negative and optochin resistant)
beta hemolytic bacteria?
staph aureus (catalase, coagulase +)
strep pyogenes (catalase -, bacitracin sensitive)
strep agalactiae (catalase -, bacitracin resistant)
listeria
how do you differentiate strep pyogenes form strep agalactiae?
strep pyogenes - bacitracin sensitive
strep agalactiae - bacitracin resistant
obligate aerobes (4)
Nagging Pests Must Breathe
nocardia, pseudomonas, mycobacterium TB, bacillus
obligate anaerobes (3)
clostridium, bacteriodes, actinomyces - lack catylase and/or superoxide dismutase, and thus are susceptible to oxidative damage; generally foul smelling, difficult to culture, and produce gas in tissue (CO2 and H2)
obligate intracellular bugs (2)
rickettsia, chlamydia (stay inside when it's Really Cold)
facultative intracellular (8)
Some Nasty Bugs May Live FacultativeLY:
salmonella, neisseria, brucella, mycobacterium, listeria, francisella, legionella, yersinia
encapsulated bugs (4)
strep pneumo, H. flu, neisseria meningitidis, klebsiella - positive quellung reaction
bacillus anthracis, c. perfringens, and c. tetani form what?
spores (gram positive soil bugs)
alpha hemolytic bacteria?
strep pneumo (catalase negative and optochin sensitive)
viridans strep (catalase negative and optochin resistant)
beta hemolytic bacteria?
staph aureus (catalas, coagulase +)
strep pyogenes (catalase negative, bacitracin sensitive)
strep agalactiae (catalase -, bacitracin resistant)
listeria
how do you differentiate strep pyogenes form strep agalactiae?
strep pyogenes - bacitracin sensitive
strep agalactiae - bacitracin resistant
DNA transferred from 1 bacterium to another
conjugation
nature of DNA transferred in conjugation
chromosomal or plasmid
DNA transferred by a virus from 1 cell to another
transduction
nature of DNA transferred in transduction
any gene in generalized transduction; only certain genes in specialized transduction
purified DNA taken up by a cell
transformation (any DNA)
most capsules are made out of polysaccharide except bacillus anthracis, which contains what?
d-glutamate
chemical composition of spore?
keratin-like coat; dipicolinic acid - provides resistance to heat, dehydration, and chemicals
what is a pilus made out of?
glycoprotein
location of exotoxin genes?
plasmid or bacteriophage
location of endotoxin genes?
bacterial chromosome
which is antigenic - exotoxin or endotoxin?
exotoxin
both of these bugs activate EF-2
corynebacterium, pseudomonas (exotoxin A)
how do you distinguish staph epidermidis from staph saprophyticus
epidermidis - novobiocin sensitive
saprophyticus - novobiocin resistant
another name for group A beta hemolytic strep?
strep pyogenes
another name for group B beta hemolytic strep?
strep agalactiae
which is bile soluble - strep pneumo or strep viridans?
strep pneumo
oxidase positive non-lactose fermenter?
pseudomonas
oxidase-negative non-lactose fermenters?
shigella, salmonella, proteus
positive quellung reaction indicates what?
presence of a capsule (strep pneumo, h. flu, neisseria meningitidis, klebsiella)
prokaryotes with axial filaments
spirochets - borrelia, leptospira, treponema
type of strep that can cause glomerulonephritis?
strep pyogenes - bacitracin sensitive
strep strains that cause scarlet fever contain what compared to strains that don't?
phage
coagulase negative, non-hemolytic, novobiocin sensitive?
staph epidermidis
mechanism of amantadine?
blocks viral penetration/uncoating; may buffer pH of endosome. also causes the release of dopamine from intact nerve terminals
clinical use of amantadine?
prophylaxis and treatment for influenza A; Parkinson's disease
toxicity of amantadine?
ataxia, dizziness, slurred speech
mehcanism of zanamivir, oseltamivir?
inhibit influenza neuraminidase
clinical use of zanamivir & oseltamivir?
both influenza A & B
mechanism of ribavirin?
inhibits synthesis of gruanine nucleotides by competitively inhibiting IMP dehydrogenase
clinical use of ribavirin?
RSV, chronic hepatitis C
toxicity of ribavirin?
hemolytic anemia, severe teratogen
mechanism of acyclovir?
preferentially inhibits viral DNA polymerase when phosphorylated by viral thymidine kinase; guanine analog
clinical use of acyclovir?
HSV, VZV, EBV; mucocutaneous and genital herpes lesions; prophylaxis in immunocompromised patients
toxicity of acyclovir?
delerium, tremor, nephrotoxicity
mechanism of ganciclovir?
phosphorylation by viral kinase; preferentially inhibits CMV DNA polymerase
clinical use of ganciclovir?
CMV, especially in immunocompromised patients
toxicity of ganciclovir?
leukopenia, neutropenia, thrombocytopenia, renal toxicity; more toxic to host enzymes then acyclovir
mechanism of foscarnet?
viral DNA polymerase inhibitor that binds to the pyrophosphate binding site of the enzyme; does not require action by viral kinase
clinical use of foscarnet?
CMV retinitis in immunocompromised patients when ganciclovir fails; acyclovir-resistant HSV
toxicity of foscarnet?
nephrotoxicity, hypoglycemia, hypomagnesia
saquinavir, ritonavir, indinavir, nelfinavir, and amprenavir are what type of drugs?
protease inhibitors - used in HIV therapy
mechanism of protease inhibitors?
inhibit assembly of new virus by blocking protease enzyme
toxicity of protease inhibitors?
GI intolerance (nausea, diarrhea), hyperglycemia, lipid abnormalities
protease inhibitor that can cause thrombocytopenia?
indinavir
zidovudine, didanosine, zalcitabine, stavudine, lamivudine, and abacavir are what type of drug?
nucleoside RT inhibitors
nevirapine, delaviridine, and efavirenz are what type of drug?
non-nucleoside RT inhibitors
mechanism of reverse transcriptase inhibitors?
preferentially inhibit RT of HIV; prevent incorporation of viral genome into host DNA
toxicity of RT inhibitors?
bone marrow suppression (neutropenia, anemia), peripheral neuropathy
what type of reverse transcriptase inhibitors can cause lactic acidosis?
nucleosides - zidovudine, didanosine, zalcitabine, stavudine, lamivudine, and abacavir
what type of RT inhibitors can cause rash?
non-nucleosides -nevirapine, delaviridine, and efavirenz
nucleoside RT inhibitor that can cause megaloblastic anemia?
AZT (zidovudine)
what HIV drug is used during pregnancy to reduce the risk of fetal transmission?
AZT
interferon-alpha is used for what?
chronic hepatitis B andC, Kaposi's sarcoma
interferon beta is used in what disease?
MS
interferon gamma is used in what disease?
NADPH oxidase deficiency
toxicity of interferons?
neutropenia
these are glycoproteins from human leukocytes that block various stages of viral RNA and DNA synthesis
interferons
drug used for giardiasis, amebic dysentery, bacterial vaginitis, trichomonas?
metronidazole
drug used for giant roundworm (asarcis), hookworm (necator/ancylostoma), and pinworm (enterobius)?
pyrantel pamoate
drug used for trematode/fluke (schistosomes, paragnimus, clornorchis), and cysticercosis?
praziquantel
drug used for cestode/tapeworm (e.g. diphyllobothrium latum, taenia species) infections except cysticercosis?
niclosamide
drug used for onchocerciasis?
ivermectin (rIVER blindness)
drug used for nematode/roundworm (e.g. pinworm, whipworm) infections?
mebendazole/thiabendazole
block cell wall synthesis by inhibition of peptidoglycan cross-linking
penicillin, ampicillin, ticarcillin, piperacillin, imipenem, aztreonam, cephalosporins
block peptidoglycan synthesis
bacitracin, vancomycin, cycloserine
disrupt bacterial/fungal cell membranes
polymyxins
disrupt fungal cell membranes
amphotericin B, nystatin, fluconazole/azoles
block nucleotide synthesis
sulfonamides, trimethoprim
block DNA topoisomerases
quinolones
block mRNA synthesis
rifampin
block protein synthesis at 50S ribosomal subunit
chloramphenicol, erythromycin/macrolides, lincomycin, clindamycin, streptogramins (quinupristin, dalfopristin), linezolid
block protein synthesis at 30S ribosomal subunit
aminoglycosides, tetracyclines
bacteriacidal antibiotics (6)
penicilin, cephalosporins, vancomycin, aminoglycosides, fluoroquinolones, metronidazole
penicillin mechanism
bind PBPs, block transpeptidase cross-linking of cell wall; activate autolytic enzymes
penicillin toxicity
hypersensitivity reactions, hemolytic anemia
mechanism of methicillin, nafcillin, dicloxacillin
bind PBPs, block transpeptidase cross-linking of cell wall - penicillinase resistant because of bulkier R group
methicillin toxicity
interstitial nephritis
ampicillin, amoxicillin toxicity
hypersensitvity, ampicillin rash (esp. in pts. w/ mono), pseudomembranous colitis
ticarcillin, carbenicillin, piperacillin usage
pseudomonas (Takes Care of Pseudomonas)
mechanism of cephalosporins
beta-lactam drugs that inhibit cell wall synthesis - less susceptible to penicillinases
antibiotic for penicillin-allergic patients and patients w/ renal toxicity who can't tolerate aminoglycosides
aztreonam (synergistic w/ aminoglycosides)
drug of choice for enterobacter
imipenem/cilastin
antibiotic that can cause seizures at high plasma levels
imipenem/cilastin
mechanism of vancomycin
inhibits cell wall mucopeptide formation by binding D-ala D-ala portion of cell wall precursors
mechanism of resistance to vancomycin
amino acid change of D-ala D-ala to D-ala D-lac
vancomycin toxicity
well tolerated in general - does NOT have many problems: nephrotoxicity, ototoxicity, thrombophlebitis
aminoglycosides
streptomycin, gentamicin, tobramycin, amikacin - bacteriacidal
mechanism of action of aminoglycosides
inhibit 30S subunit - inhibit formation of initiation complex and cause misreading of mRNA
are aminoglycosides effective agains anaerobes?
no! require O2 or uptake
aminoglycosides cause nephrotoxicity especially when used in combination with _________
cephalosporins
aminoglycosides cause ototoxicity especially when used with_________
loop diuretics
are aminoglycosides safe to use in pregnancy?
no! teratogenic
which tetracycline can be used in patients with renal failure?
doxycycline because it is fecally eliminated
can you take tetracyclines with milk?
no! nor atacids or iron-containing preparations because divalent cations inhibit its absorption in the gut
tetracycline toxicity
discoloration of teeth and inhibition of bone growth in children, photosensitivity
mechanism of action of macrolides
inhibit protein synthesis by blocking translocation - bind to 23S rRNA of the 50S subunit
name 3 macrolides
erythromycin, azithromycin, clarithromycin
when can sulfonamides cause hemolysis?
G6PD deficiency
most common cause of noncompliance with macrolides
GI discomfort
macrolides increase the serum concentration of what drugs?
theophyllines, oral anticoagulants
acute cholestatic hepatitis & eosinophilia are toxicities of which class of antibiotics?
macrolides
clinical use of chloramphenicol
meningitis - H. flu, neisseria, strep pneumo
why does chloramphenicol cause gray baby syndrome?
because infants lack liver UDP-glucoronyl transferase
is the aplastic anemia seen with chloramphenicol dose dependent?
no! the anemia is, however
mechanism of action of chloramphenicol
inhibits 50S peptidyltransferase
what is the clinical use of clindamycin?
treatment of anaerobic infections - B. frag, C. perfringfens
clindamycin toxicity
pseudomembranous colitis - destroys normal GI flora
mechanism of action of sulfonamides (sulfamethoxazole, sulfisoxazole, triple sulfas, etc.)
PABA antimetabolites inhibit dihydropteroate synthase
what side effect can sulfonamides cause in infants?
kernicterus
mechanism of action of trimethoprim
inhibits bacterial dihydrofolate reductase
trimethoprim toxicity
megaloblastic anemia, leukopenia, granulocytopenia (may alleviate with supplemental folinic acid)
mechanism of action of fluoroquinolones
inhibit DNA gyrase (topoisomerase II)
what class of antibiotics can cause cartilage damage in kids?
fluoroquinolones
what drug is associated with a disulfiram-like reaction with alcohol and a metallic taste
metronidazole
what can prevent the neurotoxicity associated with INH?
pyridoxine (vitamin B6)
INH toxicity
hemolysis if G6PD deficient, neurotoxicity, hepatotoxicity, SLE-like syndrome
mechanism of action of rifampin
inhibits DNA-dependent RNA polymerase
what drug delays resistance to dapsone when used for leprosy?
rifampin
resistance mechanism for penicillins/cephalosporins
beta-lactamase cleavage of beta lactam ring
resistance mechanism for aminoglycosides
modification via acetylation, adenylation, or phosphorylation
resistance mechanism for chloramphenicol
modification via acetylation
resistance mechanism for macrolides
methylation of rRNA near erythromycin's ribosome binding site
resistance mechanism for tetracycline
decreased uptake or increased transport out of cell
resistance mechanism for sulfonamides
altered enzyme (bacterial dihydropteroate synthetase), decreased uptake, or increased PABA synthesis
mechanism of action of amphotericin B
binds ergosterol (unique to fungi); forms membrane pores that allow leakage of electrolytes and disrupt homeostasis
drug of choice for systemic mycoses
amphotericin B
amphotericin B toxicity
fever/chills, hypotension, nephrotoxicity, arrhythmias, hypochromic normocytic anemia
do ketoconazole and ampho B act synergistically?
no - they antagonize each other's actions, so should never be used together
which has greater oral availability - amoxicillin or ampicillin?
amOxicillin
spectrum of ampicillin, amoxicillin
HELPS kill enterococci:
h. flu, e. coli, listeria, proteus, salmonella, enterococci
cefazolin and cephalexin are what generation cephalosporins?
first
coverage of cefazolin and cephalexin?
PEcK:
proteus, e. coli, klebsiella
(and gram-positives)
cefoxitin, cefaclor, cefuroxamine are what generation?
second
coverage of cefoxitin, cefaclor, cefuroxamine?
HEN PEcKS:
h. flu, enterobacter, neisseria, proteus, e. coli, klebsiella
ceftriaxone, cefotaxime, and ceftazidime are what generation?
third
use of ceftriaxone, cefotaxime, and ceftazidime?
serious gram-negative infections resistant to other beta lactams; meningitis; ex. ceftazidime for pseudomonas, ceftriaxone for gonorrhea
cefepime, cefpiramide belong to what generation?
fourth
use of cefepime, cefpiramide?
increased activity against pseudomonas and gram-positive organisms
serum-like sickness in infants and kids can be seen with what cephalosporin?
ceflacor (2nd generation)
this is an inhibitor of renal dihydropeptidase I
cilastin - decreases inactivation of imipenem in renal tubules
why are aminoglycosides ineffective against anaerobes?
require O2 for uptake
drug used for bowel surgery?
neomycin
this tetracycline is an ADH antagonist - acts as a diuretic in SIADH
demeclocylcine
clinical use of tetracyclines?
VACUUM THe BedRoom: vibrio cholerae, acne, chlamydia, ureaplasma urealyticum, mycoplasma, tularemia, h. pylori, borrelia burgdorferi, rickettsia
this drug treats anaerobes above the diaphragm
clindamycin
these drugs can cause leg cramps and myalgias in kids
fluoroquinolones
used for anaerobes below the diaphragm
metronidazole
how does nystatin work?
binds to ergosterol, disrupting fungal membranes (too toxic for systemic use)
mechanism of the -azoles?
inhibit fungal steriod (ergosterol) synthesis
toxicities of -azoles?
hormone synthesis inhibition (gynecomastia), liver dysfunction (inhibition of P450), fever, chills
this antifungal inhibits DNA synthesis by conversion to fluorouracil, which competes with uracil
flucytosine
toxicity of flucytosine
nausea, vomiting, diarrhea, bone marrow suppression
mechanism of caspofungin?
inhibits cell wall syntehsis
use of caspofungin?
invasive aspergillosis
toxicity of caspofungin?
GI upset, flushing
this antifungal inhibits the fungal enzyme squalene epoxidase
terbinafine
use of terbinafene?
used to treat dermatophytoses (especially onychomycosis)
mechanism of griseofulvin?
interferes with microtubule function; disrupts mitosis; depostis in keratin-containing tissues (e.g. nails)
clinical use of griseofulvin?
oral treatment of superficial infections; inhibits growth of dermatophytes (tinea, ringworm)
toxicity of griseofulvin?
teratogenic, carcinogenic, confusion, headaches, increases warfarin metabolism
two diseases transmitted by inhalation fo asexual spores?
coccidiomycosis and histoplasmosis
treatment for superficial candidal infection? for systemic?
nystatin; amphotericin B
Southwestern US, valley fever
coccidiomycosis
Mississippi and Ohio river valleys
histoplasmosis
rural Latin America
paracoccidiomycosis
bird or bat droppings; intracellular (tiny yeast inside macrophages)
histoplasmosis
Captain's wheel appearance
paracoccidiomycosis
states east of Mississippi River and Central America
blastomycosis
big, broad-based budding
blastomycosis
dimorphic fungi
mold in soil; yeast in tissue
on what do you culture fungi?
Sabouraud's agar
systemic mycoses can mimic what?
TB (granuloma formation)
what is cocidiomycosis in tissue?
spherule
treatments for mycoses?
fluconazole or ketoconazole for local infection; ampho B for systemic infection
what causes tinea versicolor?
malassezia furfur
hypopigmented skin lesions in hot, humid weather
tinea versicolor
treatment for tinea versicolor?
topical miconazole, selenium sulfide
what does cladosporium werneckii cause?
tinea nigra
infection of keratinized layer of skin; appears as brownish spot
tinea nigra
treatment for tinea nigra?
salicylic acid
pruritic lesions with central clearing resembling a ring, caused by dermatophytes
tinea pedis/cruris/corporis/capitis
mold hyphae in KOH prep, not dimorphic
tinea pedis/cruris/corporis/capitis
mold with septate hyphae that branch at a V-shaped (45 degree) angle
aspergillus
culture on Sabourauds' agar, stains with India ink?
cryptococcus neoformans
heavily encapsulated yeast, not dimorphic, found in soil & pigeon droppings
cryptococcus
fungus ball
aspergillus
mold with irregular nonseptate hyphae branching at wide angles (>90 degrees)
mucor and rhizopus
in what type of patients is mucormycosis typically seen?
ketoacidotic diabetic and leukemic patients
fungi proliferate in walls of blood vessels and cause infarction of distal tissue; rhinocerebral, frontal lobe abscesses
mucor and rhizopus
yeast that causes diffuse interstitial pneumonia
pneumocystis cainii
how do you diagnose PCP?
lung biopsy or lavage
methenamine silver stain of lung tissue identifies what?
pneumocystis carinii
treatmetn for PCP?
TMP-SMX, pentamidine, dapsone
dimorphic fungus that lives on vegetation
sporothrix schenckii
cigar-shaped budding yeast visible in pus
sporothrix schenckii
treatment for sporothrix schenckii?
itraconazole or potassium iodide
bloody diarrhea, liver abscess, RUQ pain?
entamoeba histolytica
severe diarrhea in AIDS, mild disease (watery diarrhea) in non-HIV
cryptosporidium
brain abscess in HIV, brain defects (ring-enhancing lesions)
toxoplasma
foul smelling, greenish discharge; itching and burning
trichomonas vaginalis
dilated cardiomyopathy, megacolon, megaesophagus
trypanosoma cruzi (Chags' disease)
African sleepign sickness
trypanosoma gambinse, rhodesiense
visceral leishmaniasis (kala-azar)
leishmania donovani
rapidly fatal menigoencephalitis; swimming in freshwater lakes
naegleria
appears as maltese cross on blood smear
babesia
trophozoites on wet mount
trichomonas vaginalis
cysts on acid-fast stain
cryptosporidium
trophozoites or cysts in stool (2)
giardia, entamoeba
transmission of entamoeba, giradia, cryptosporidium?
cysts in water
transmission of toxoplasma?
cysts in meat or cat feces
transmission of babesia?
ixodes tick
transmission of leishmania?
sandfly
transmission of african sleeping sickness?
tsetse fly
undercooked pork tapeworm; larvae cause mass lesions in brain, cysticercosis
taenia solium (tapeworm/cestode)
eggs in dog feces when ingested can cause cysts in liver; causes anaphylaxis if antigens are released from cysts
echinococcus granulosus (cestode/tapeworm)
snails are host; cercariae penetrate skin of humans; causes granulomas, fibrosis, and inflammation of the spleen and liver
schistosoma (trematode/fluke)
undercooked fish; causes inflammation of the biliary tract
clonorchis sinensis (trematode/fluke)
undercooked crab meat; causes inflammation and secondary bacterial infection of the lung
paragonimus westermani (trematode/fluke)
larvae penetrate skin of feet; intestinal infection can cause anemia
ancylostoma duodenale (hookworm)
eggs are visible in feces; intestinal infection
asarcis lumbicoides (giant roundworm)
food contaminated with eggs; intestinal infection; causes anal pruritis
enterobius vermicularis (pinworm)
larvae in soil penetrate the skin; intestinal infection
strongyloides stercoralis
undercooked meat, usually pork; inflammation of muscle, periorbital edema
trichinella spiralis
in drinking water; skin inflammation and ulceration
dracunculus medinensis
transmitted by deer fly; causes swelling in skin (can see worm crawling in conjuctiva)
loa loa
transmitted by female blackflies; causes river blindness
onchocera volvulus
food contaminated with eggs; causes granulomas (if in retina leads to blindness) and visceral larva migrans
toxocara canis
female mosquito; causes blockage of lymphatic vessels (elephantiasis)
wuchereria bancrofti
parasite: brain cysts, seizures
taenia solium
parasite: liver cysts
echinococcus granulosus
parasite: B12 deficiency
diphyllobothrium latum
parasite: biliary tract disease
clonorchis sinensis
parasite: hemoptysis
paragonimus westermani
parasite: portal hypertension
schistosoma mansoni
parasite: hematuria, bladder cancer
schistosoma haematobium
parasite: microcytic anemia
ancylostoma, necator
parasite: perianal pruritis
enterobius
outbreaks after cleaning chicken coops or exploring caves
histoplasmosis
what type of fungus is cryptococcus?
yeast, not dimorphic
cauliflower skin lesions; broad based budding yeasts
blastomyces
how do you diagnose trichinella?
muscle biopsy
RMSF-type symptoms plus berry-like clusters (morulae) inside neutrophils?
anaplsma phagocytophilium
what causes human granulocytic erlichiosis?
anaplasma phagocytophilium
asarcis lumbricoides, clonorchis seinensis, and fascida hepatica can all cause what?
bacterial cholangitis
what types of milaria have dormant forms?
p. vivax and p. ovale
species of malaria that can cause severe (cerebral) disease?
p. falciparum
malaria drug to prevent relapse caused by p. vivax, p. ovale?
primaquine
all DNA viruses except what are dsDNA?
parvoviridae (part-of-a-virus)
all DNA viruses are linear except what?
papovaviruses (circular, supercoiled), hepadnaviruses (circular, incomplete)
name 3 naked RNA viruses?
calcivirus, picornavirus, reovirus (naked CPR)
this type of virus acquires envelopes from the nuclear membrane
herpesvirus
most enveloped viruses aquire their envelope from where?
from plasma membrane when they exit from cell
all viruses are haploid except what?
retroviruses, which have 2 identical ssRNA molecules (diploid)
all DNA viruses replicate where? what is the exception?
nucleus - except poxvirus
all RNA viruses replicate where? what are the exceptions?
cytoplasm - except influenza and retroviruses
name the DNA viruses
HHAPPPy viruses: hepadna, herpes, adeno, pox, parvo, papova
this DNA virus carries its own DNA-dependent RNA polymerase
poxvirus
all DNA viruses are icosahedral except what?
pox (complex)
naked DNA viruses (3)
PAP: parvo, adeno, papova
enveloped DNA viruses (3)
HPH: hepadna, pox, herpes
what is the largest DNA virus?
poxvirus
virus causing febrile pharyngitis, pneumonia, conjunctivitis
adenovirus
virus causing aplastic crises in sickle cell disease, fifth disease, hydrops fetalis?
parvovirus
what is the smallest DNA virus?
parvovirus (ss linear)
HBV is a member of what virus family?
hepadnavirus - DNA, partial circular
members of the picornavirus family?
PERCH:
poliovirus
echovirus
rhinovirus
coxsackievirus
HAV
HEV and Norwalk virus belong to what family?
calciviruses - RNA (ss, linear), icosahedral
virus causing roseola (exanthem subitum)
HHV-6
virus related to Kaposi's sarcoma?
HHV-8
what type of virus is JC - causes PML in HIV
papovavirus
type of virus causing Colorado tick fever?
reovirus
number one cause of fatal diarrhea in kids?
rotavirus
togaviruses (3)?
rubella, EEE, WEE
flaviviruses (5)?
HCV, yellow fever, dengue, St. Louis encephalitis, West Nile virus
to what family does influenza virus belong?
orthomyxovirus
paramyxoviruses (4)
PaRaMyxovirus:
parainfluenza - croup
RSV
measles
mumps
Rx for RSV bronchiolitis in kids?
ribavirin
what type of virus is rabies?
rhabdovirus
what type of virus is HDV?
deltavirus
MMR, Sabin polio, VZV, yellow fever, smallpox, and adenovirus have what type of vaccine?
live attenuated
rabies, infulenza, HAV, and Salk polio are what type of vaccine?
killed
egg-based vaccines?
FRY an egg:
Flu, MMR, Yellow fever
the vaccine for what is recombinant?
HBV- antigen is recombinant HBsAg
exchange of genes between 2 chromosomes by crossing over within regions of significant base sequence homology
recombination
when viruses with segmented genomoes (e.g. influenza) exchange segments. high-frequency virus recombination; cause of worldwide pandemics
reassortment
when 1 of 2 viruses that infect the cell has a mutation that results in a nonfunctional protein; the nonmutated virus complemetns the mutated one by making a functional protein that serves both viruses
complementation
genome of virus A can be coated with the surface proteins of virus B; type B protein coat determines the infectivity of the phenotypically mixed virus; however, the progeny from this infection has a type A coat and is encoded by type A genetic material
phenotypic mixing
DNA enveloped viruses (3)
herpesvirus, HBV, smallpox
DNA nucleocapsid viruses (3)
adenovirus, papillomaviruses, parvovirus
influenza virus, parainfluenza, RSV, measles, mumps, rubella, rapies, HTLV, and HIV are what type of RNA viruses?
RNA enveloped viruses
enteroviruses (poliovirus, coxsackie virus, echovirus, HAV), rhinovirus, and reovirus are what type of RNA viruses?
RNA nucleocapsid
segmented viruses?
all are RNA viruses: BOAR
bunyaviruses, orhtomyxoviruses, arenaviruses, and reoviruses
all paramyxoviruses have 1 serotype except what?
parainfluenza virus - has 4
parainfluenza, mumps, measles, and RSV all belong to what family?
paramyxoviruses
parotitis, orchitis, and aseptic meningitis?
mumps
bluish-gray spots on buccal mucosa?
Koplik spots - diagnostic for measles
drugs for influenza A?
amantadine and rimantadine (especially prophylaxis)
drugs useful for both influenza A and B?
zanamivir and oseltamivir (neuraminidase inhibitors)
virus with a bullet-shaped capsid?
rabies
how does rabies travel to CNS?
migrates in a retrograde fashion up axons
variant of dengue fever in Southeast Asia?
hemorrhagic shock syndrome
caused by flavivirus, an arbovirus transmitted by Aedes mosquitos
yellow fever
high fever, black vomit, jaundice
yellow fever
councilman bodies (acidophilic inclusions) may be seen in liver with this virus
yellow fever
virus causing mono with negative monospot?
CMV
heterophil antibodies detected by agglutination of sheep RBCs?
monospot test
tzanck test
a smear of opened skin vesicle to detect multinucleated giant cells - used to assay for HSV-1, HSV-2, and VZV
hepatitis RNA picornavirus
HAV
hepatitis DNA hepadnavirus
HBV
hepatitis RNA flavivirus
HCV
hepatitis delta virus
HDV
hepatitis RNA calcivirus
HEV
how is HAV trasmitted?
fecal-oral
type of hepatitis that is transmitted enterically and causes water-borne epidemics
HEV
defective virus that requires HBsAg as its envelope
HDV
common cause of transfusion-mediated hepatitis
HCV
best test to detect active hepatitis A?
IgM HAVAb
continued presenc of what indicates carrier state of HBV?
HBSAg
provides immunity to HBV
HBsAb
positive during the window period of HBV
HBcAb
HBV vaccination - what serologic marker is seen?
HBsAb only
rectangular nucleocapsid protein of HIV?
p24
HIV envelope proteins?
gp41 and gp120
what crosses placenta in HIV infected mothers
anti-gp120
CXCR1 mutation
rapid progression to AIDS
CCR5 mutation
homozygous - immunity (1% U.S. caucasians)
heterozygous - slower course (20% U.S. caucasians)
infectious agents that don't contain DNA or RNA, just protein
prions
normal prions have what? pathologic prions are what?
normal - alpha helix
pathologic (like CJD) - beta pleated sheets
virus family of HPV?
papovavirus
aseptic meningitis, herpangina - febrile pharyngitis, hand, foot, and mouth disease, myocarditis
coxsackievirus - picornavirus
rotavirus belongs to what family?
reovirus - DS linear segmented RNA
hemorrhagic fever, pneumonia, RDS in NM, AZ, CO, UT
hantavirus - member of bunyavirus family (SS circular RNA; helical capsid)
ebola/marburg are what types of viruses?
filoviruses - SS linear RNA, helical capsid
triad of cutaneous hemorrhages, deafness, and periventricular CNS calcifications in a neonate
congenital CMV infection
virulence factor of staph aureus - binds Fc-IgG, inhibiting complement fixation and phagocytosis
protein A
superantigen that binds to MHC II and TCR, resulting in polyclonal T cell activation
TSST - (staph aureus)
what makes coagulase?
staph aureus
antibody to what enhances host defenses against strep pyogenes?
M protein
group A beta-hemolytic strep?
strep pyogenes
what detects recent strep pyogenes infections?
ASO titer
associated with rusty sputum, sepsis in sickle cell, and splenectomy?
strep pneumo
most common cause of meningitis, otitis, pneumonia, sinusitis?
strep pneumo
what gives immunity to strep pneumo?
IgG antibodies to surface acidic polysaccharide
causes pneumonia, meningitis, and sepsis mainly in babies
group B strep (agalactiae) - beta hemolytic, bacitracin resistant
what is Lancefield grouping based on?
differences in the C carbohydrate on the bacterial cell wall
what can grow in 6.5% NaCl
enterococci
enterococci can cause what?
UTI, subacute endocarditis, biliary tract infections
bacteria related to colon cancer?
strep bovis
type of strep viridans that can cause subacute bacterial endocarditis?
strep sanguis
what does C. perfringens produce?
alpha toxin
gram-positive rods with metachromatic granules?
corynebacterium diphtheriae
woolsorter's disease?
bacillus anthracis
inhalation of anthrax spores?
flulike symptoms that rapidly progress to fever, pulmonary hemorrhage, and shock
gram-positive anaerobe that causes oral/facial abscesses that may drain through sinus tracks in skin
actinomyces
gram positive, weakly-acid fast aerobe that causes pulmonary infection in immunocomprimised patients
nocardia asteroides
sulfur granules
actinomyces
gram-positive rods forming long branching filaments resembling fungi
actinomyces & nocardia
most invasive disease of H. flu is caused by what capsular type?
B
treatment for H. flu meningitis?
ceftriaxone
treatment for neisseria gonorrhea?
ceftriaxone - also z pack or doxycycline because 50% will also be infected with chlamydia
why don't you want to culture if pt. has epiglottitis?
manipulation cause laryngeal spasm
members of enterobacter family (7)
e. coli, salmonella, shigella, klebsiella, enterobacter, serratia, proteus
what antigen is related to the virulence of enterobacter?
K antigen
all of these ferment glucose and are oxidase negative
enterobacter
these bacteria grow pink colonies on MacConkey's agar
klebsiella, e. coli, enterobacter (KEE), citrobacter
salmonella or shigella: motile and can disseminate hematogenously?
salmonella
salmonella or shigella: which is more virulent?
shigella
salmonella or shigella: symptoms may be prolonged with antibiotic treatments
salmonella
salmonella or shigella: animal reservoir
salmonella
this is usually transmitted from pet feces, contaminated milk, or pork; outbreaks common in daycare centers
yersinia enterocolitica
this can mimic Crohn's or appendicitis & can disseminate to produce lymphadenitis
yersinia enterocolitica
arthritis can develop with yersinia infection in patients with what?
HLA-B27
vibrio parahaemolyticus and v. vulnificus
contaminated seafood
reheated rice
B. cereus
meats, mayonase, custard
s. aureus
reheated meat dishes
c. perfringens
undercooked meat
e. coli 0157:H7
poultry, meat, eggs
salmonella
bloody diarrhea; comma or S-shaped organisms
campylobacter
is campylobacter motile?
yes
e. coli producing shiga-like toxin; can cause HUS
enterohemorrhagic
day-care outbreaks, pseudoappendicitis
yersinia
protazoan causing bloody diarrhea
entamoeba histolytica
protaozoa causing watery diarrhea
giardia, cryptosporidium (in immunocompromised)
treatment for legionella?
erythromycin
UTI - urine with alkaline pH
proteus - very motile - able to break down urea
pneumonia in CF
pseudomonas
wound and burn infections
pseudomonas
treatment for pseudomonas?
amnoglycoside plus extended-spectrum penicillin (piperacillin, ticarcillin)
aerobic gram-negative rod; oxidase positive, non-lactose fermenting; pyocyanin pigment
pseudomonas
hot tub folliculitis
pseudomonas
pneumonia, sepsis, UTI, drug use and diabetic osteomyelitis
pseudomonas
cellulitis from animal bite, cats, dogs
pasteurella
dairy products, contact with animals
brucella
ghon complex
TB granulomas (Ghon focus) with lobar and perihilar LN involvement; reflects primary infection or exposure
mycobacterium scrofulaceum
cervical lymphadenitis in kids
mycobacterium kansasii
pulmonary TB-like symptoms
acid-fast bacillus that likes cold temperatures and cannot be grown in vitro
mycobacterium leprae
reservoir for m. leprae in U.S.?
armadillos
what does m. leprae infect?
skin and superficial nerves
treatment for leprosy?
long-term oral dapsone - toxicity is hemolysis and methemoglobinemia
which type of Hanson's diseaseiis worse?
lepromatous worse than tuberculoid
the chlamydial petidoglycan wall is unusual in that it lacks what?
muramic acid
treatment for chlamydia?
erythromycin or tetracycline
cytoplasmic inclusions seen on Giemsa or fluorescent antibody-stained smear
chlamydia
infection of liver capsule with RUQ pain; associated with chlamydial or gonococcal infection
Fitz-Hugh-Curtis syndrome
how do the reticulate bodies of chlamydia replicate?
binary fission
types A, B, and C of chlamydia
Africa/Blindness/Chronic infection
types D-K of chlamydia
urethritis/PID, ectopic pregnancy, neonatal pneumonia or conjunctivitis
types L1, L2, and L3 of chlamydia
lymphogranuloma venereum (acute lymphadenitis - positive Frei test)
treatment for neonate after passage through chlamydia-infected birth canal?
erythromycin eye drops
most common STD in U.S.?
chlamydia
only spirochete that can be visualized using analine dyes (Wright's or Giemsa stan) in light microscopy
borrelia
shepherd's crook-shaped spirochete
leptospira
Wal's disease
fatal from of leptospira infection - jaundice, bleeding, renal failure, skeletal muscle necrosis
treatment for Borrelia recurrentis?
doxycycline, erythromycin
treatment for Lyme disease?
doxycycline
what causes yaws?
tremonema pertenue - tropical infection that is not an STD, although VDRL test is positive
what are important reservoirs for ixodes? what is required for tick life cycle?
mice; deer
signs of tertiary syphilis?
broad-based ataxia; positive Romberg; Charcot joints; stroke without hypertension
congenital syphilis?
saber shins, saddle nose, deafness
primary syphilis?
painless chancre
secondary syphilis?
disseminated isease with constitutional symptoms, maculopapular rash (palms and soles), condylomata lata
VDRL positive, FTA positive?
active infection
VDRL positive, FTA negative?
probably false positive
VDRL negative, FTA positive?
successfully treated
VDRL false positives?
Viruses (mono, hepatitis)
Drugs
Rheumatic fever and rheumatic arthritis
Lupus and leprosy
Weil-Felix reaction?
classic test that uses cross-linking proteus antigens to confirm diagnosis of rickettsia
strep associated with pharyngitis, cellulitis, impetigo, scarlet fever, TSS, rheumatic fever, glomerulonephritis?
strep pyogenes (group A beta hemolytic)
characteristics of rheumatic fever?
subcutaneous nodules, erythema marginatum, chorea, carditis
tumbling motility, menigitis in newborns, unpasteurized milk
listeria monocytogenes
virulence factor of staph aureus?
protein A
what does c. difficile produce?
a cytotoxin, an exotoxin that kills enterocytes, causing pseudomembranous colitis
what encodes the exotoxin of corynebacterium diphtheriae?
beta-prophage
gram-positive rods with metachromatic granules?
corynebacterium diphtheriae
vesicular papules covered y black eschar
bacillus anthracis
what part of gram-negative bugs inhibits entry of penicillin and vancomycin?
the outer membrane layer
this vaccine contains type B capsular polysaccharide conjugated to diphtheria toxoid or other protein
h. flu
flagellar antigen of enterobacter?
H antigen
somatic antigen of enterobacter?
O antigen (polysaccharide of endotoxin)
viruses causing watery diarrhea?
rotavirus, adenovirus, norwalk virus
pertussis toxin permanently disables what?
Gi
cholera toxin permanently activates what?
Gs
how does pertussis toxin promote lymphocytosis?
by inhibiting chemokine receptors
treatment of choice for most rickettsial infections?
tetracycline
classic triad of rickettsiae?
headache, fever, rash (vasculitis)
rickettsiae are obligate intracellular parasites and need what?
CoA and NAD
all rickettsiae except what are transmitted by an arthropod vector and cause headache, fever, and rash?
coxiella
why is coxiella an atypical rickettsia?
because it is transmitted by aerosol and causes pneumonia
what causes rocky mountain spotted fever? to where is it endemic?
rickettsia rickettsii; endemic to east coast
vector for rocky mountain spotted fever?
tick; rickettsia rickettsii
vector for endemic typhus?
fleas; rickettsia typhi
vector for epidemic typhus?
human body louse; rickettsia prowazekii
what causes Q fever?
coxiella burnetii
rickettsial disease with no rash, no vector, negative Wiel-Felix, and casative organism can survive outside for a long time
coxiella burnetii
what does the Weil-Felix reaction assay for?
antirickettsial antibodies, which cross-react with proteus antigen
what is the only bacterial membrane containing cholesterol?
mycoplasma pneumoniae
growth on Eaton's agar?
mycoplasma pneumoniae
normal flora dominant in nose
staph aureus
normal flora dominant in skin
staph epidermidis
normal flora dominant in oropharynx
strep viridans
normal flora dominant in dental plaque
strep mutans
normal flora dominant in colon
bacteriodes fragilis > e. coli
normal flora dominant in vagina
lactobacillus, colonized by e. coli and group B strep
common causes of pneumonia in kids (6 wks. - 18 yrs)
viruses (RSV)
mycoplasma
chlamydia pneumoniae
strep pneumo
common causes of pneumonia in adults (18-40)
mycoplasma
c. pneumoniae
strep pneumo
common causes of pneumonia in adults (40-65)
strep pneumo
H flu
anaerobes
viruses
mycoplasma
common causes of pneumonia in elderly
strep pneumo
viruses anaerobes
H. flu
gram-negative rods
common causes of pneumonia in nosocomial
staph, gram-negative rods
common causes of pneumonia in immunocomprimised
staph, gram-negative rods, fungi, viruses, PCP (HIV)
common causes of pneumonia in aspiration
anaerobes
common causes of pneumonia in alcoholic/IV drug user
strep pneumo, klebsiella, staph
common causes of pneumonia in postviral
staph, h. flu
common causes of pneumonia in neonate
group B strep, e. coli
common causes of atypical pneumonia
mycoplasma, legionella, chlamydia
causes of meningitis in newborn (0-6 mos)
group B strep
e. coli
listeria
causes of meningitis in children (6 mos - 6 yrs)
strep pneumo
neisseria meningitidis
H. flu type B
enteroviruses
causes of meningitis in 6-60 year olds
n. meningitidis
enteroviruses
strep pneumo
HSV
causes of meningitis in elderly (over 60)
strep pneumo
gram negative rods
listeria
causes of meningitis in HIV
cryptococcus, CMV, toxoplasmosis (brain abscess), JC virus (PML)
CSF findings in bacterial meningitis
increased pressure
increased neutrophils
increased protein
decreased sugar
CSF findings in fungal/TB meningitis
increased pressure
increased lymphocytes
increased protein
decreased sugar
CSF findings in viral meningitis
normal/increased pressure
increased lymphocytes
normal protein
normal sugar
cause of osteomyelitis in most people
staph aureus
cause of osteomyelitis in sexually active
neisseria gonorrhoeae (rare), septic arthritis more common
cause of osteomyelitis in diabetics and drug addicts
pseudomonas
cause of osteomyelitis in sickle cell
salmonella
cause of osteomyelitis in prosthetic replacement
staph aureus and staph epidermidis
cause of vertebral osteomyelitis
TB (Pott's disease)
UTI in ambulatory patients
e. coli (50-80%), klebsiella (8-10%)
second most common cause of UTI in young ambulatory women
staph saprophyticus
cause of UTI in hospital?
e. coli, proteus, klebsiella, serratia, pseudomonas
UTI - colonies show metallic sheen on EMB agar
e. coli
UTI - large mucoid capsule and viscous colonies
klebsiella
UTI - swarming on agar (motility); produces urease
proteus
vaginitis, strawberry-colored mucosa
trichomonas vaginalis
noninflammatory, malodorous discharge; positive whiff test; clue cells
gardnerella vaginalis
risk factor: newborn nursery
CMV, RSV
risk factor: urinary catheterization
e. coli, proteus
risk factor: respiratory therapy equipment
pseudomonas aeruginosa
risk factor: work in renal dialysis unit
HBV
risk factor: hyperalimentation
candida albicans
risk factor: water aerosols
legionella
infections dangerous in pregnancy
ToRCHeS:
toxoplasma
rubella
CMV
HSV/HIV
syphilis
traumatic open wound
c. perfringens
surgical wound
staph aureus
sepsis/meningitis in newborn
group B strep
neutrophils in CSF?
bacterial meningitis
normal protein and sugar in meningitis?
viral