Microbiology Flashcards
Gram Stain
Bacteria- peptidoglycan layer
except treponema, leptospira, mycobacteria, mycoplasma, ureaplasma, legionella, rickettsia, chlamydia, bartonella, anaplasma, ehrlichia
(-) pink
(+) violet
Giemsa Stain
Rickettsia, chlamydia, trypanosomes, plasmodium, borrelia, H. pylori
PAS stain
stains glycogen, mucosaccharides
Whipple disease
Ziehl Neelsen stain
Acid bast bacteria (mycobacteria, Nocardia, protozoa)
India Ink Stain
Cryptococcus neoformans
Silver stain
Fungi
Fluorescent Ab Stain
PJ, giardia and cryptosporidium
Chocolate Agar
H. influenzae
Thayer Martin agar
N. gonorrhoeae, N. meningitidis
Bordet Genou agar
B. pertussis
Tellurite agar
C. diphtheriae
Lowenstein Jensen medium
M. tuberculosis
MacConkey agar
Lactose fermenting enterics
EMB agar
E. coli
Charcoal yeast agar
Brucella, francisella, legionella, pasteurella
Obligate intracellular
Rickettsia, Chlamydia, Coxiella
Facultative intracellular
Salmonella, Neisseria, Brucella, Mycobacterium, Listeria, Francisella, Legionella, Yersinia
Encapsulated bacteria
Pseudomonas, strep, H. flu, Neisseria, E. coli, Salmonella, Klebsiella
urease (+) organisms
proteus, Cryptococcus, H. pylori, Ureaplasma, Nocardia, Klebsiella, S. epidermidis, S. saprophyticus
Pigment producing
Actinomyces israeli- yellow
S. aureus- yellow
P. aeruginosa- green
Serratia- red
Exotoxin
polypeptide secreted from cell located on pasmid or bacteriophage. high adverse effects. toxoid vaccines
Tetanus, botulism, diphtheria, cholera
Endotoxin
out cell membrane of gram (-) that is not secreted from the cell. Made of Lipid A component of LPS from bacterial chromosome. low adverse effects. cause fever, shock, DIC. Induce TNF, IL1 and IL6. No vaccines.
Meningococcemia
Corynebacterium diphtheriase
Diphtheria toxin (exotoxin) --> inactivate EF2 --> pharyngitis with pseudomembranes on throat and severe LAD, myocarditis, neuropathies Gram + rods with metachromatic granules and Elek +
Pseudomonas aeruginosa
Exotoxin A –> inactivate EF2 –> host cell death
Shigella
Shiga toxin (exotoxin) –> inactivate 60S ribosome by removing adenine from rRNA –> GI mucosal damage, dysentery, enhance cytokine release –> HUS
Enterohemorrhagic E. Coli (O157’H7)
Shiga like toxin (exotoxin) –> inactivate 60S ribosome by removing adenine from rRNA –> enhance cytokine release –> HUS
DOES NOT INVADE HOST CELL
gram -
via undercooked meat, raw leafy vegetables
Enterotoxigenic E. Coli (Heat labile)
Heat Labile toxin (exotoxin) –> overactivates adenylate cyclase (increase cAMP) –> increase Cl- secretion in gut and H2O efflux –> watery diarrhea (travelers)
gram -
Enterotoxigenic E. Coli (Heat stable)
Heat stable toxin (exotoxin) –> overactivates guanylate cyclase (increase cGMP) –>decrease resorption of NaCl and H2O in gut –> watery diarrhea (travelers)
gram -
Bacillus anthracis
Anthrax toxin (exotoxin) –> mimic adenylate cyclase –> edematous borders of black eschar in cutaneous anthrax
Gram +, spore forming rod
colonies show halo projections
Vibrio cholerae
cholera toxin (exotoxin) –> overactivates adenylate cyclase by inactivating Gs –> increase Cl- secretion in gut and H2O efflux –> rice water diarrhea
Gram -, flagella, comma shaped, oxidase +
via ingestion of water or food (shellfish)
T(x): rehydration
Bordetella pertussis
Pertussis toxin (exotoxin) --> inactivate Gi --> activate adenylate cyclase --> whooping cough Gram - Catarrhal- low grade fever Paroxysmal- whooping cough Convalescent- recovery Prevent with Tdap, DTaP T(x): macrolides or bactrim
Clostridium tetani
Tetanoplasmin (exotoxin) –> proteases that cleave SNARE –> release inhibitory neurotransmitters from Renshaw cells in spinal cord –> spastic paralysis, lockjaw
Gram +, spores, obligate anaerobe
Clostridium botulism
Botulinum toxin (exotoxin) --> proteases that cleave SNARE --> release stimulatory signals at NMJ --> flaccid paralysis, diplopia, dysarthria, dysphagia and dyspnea Gram +, spores, obligate anaerobe
Clostridium perfringens
alpha toxin (exotoxin) –> phosphilipase that degrades tissue and cell membranes –> myonecrosis and hemolysis
Gram +, spores, obligate anaerobe
Food poisoning in 10-12 hours, resolution in 24 hours
Streptococcus pyogenes
Streptolysis O (exotoxin) –> protein that degrades cell membrane –> lyse RBC, host Ab against toxin used to d(x) rheumatic fever
Staph aureus
toxic shock syndrome (exotoxin) –> cross link B region of TCR to MHC II –> overwhelming release of IL1 IL2 IFNy TNFa –> shock, fever, rash
Streptococcus pyrogenes
Erythrogenic exotoxin A –> cross link B region of TCR to MHC II –> overwhelming release of IL1 IL2 IFNy TNFa –> shock, fever, rash, scarlet fever
a hemolytic bacteria
Gram + cocci, partial oxidation of Hb --> green/brown color Strep pneumoniae (Catalase - and optochin sensitive) Viridans streptococcus (Catalase - and optochin resistant)
B hemolytic bacteria
Gram (+) cocci. Complete lysis of RBCs –>pale
S.aureus (catalase and coagulase +)
Strep pyogenes (Catalase - bacitracin sensitive)
strep agalactiae (Catalase - bacitracin resistant)
Staphylococcus aureus
Gram +, B hemolytic, catalase +, coagulase +, cocci
Protein A binds Fc-IgG –> inhibit complement.
Causes inflammatory disease, TSST
MRSA
nosocomial and community acquired infections. Resistant due to altered penicillin binding protein.
TSST
fever, vomiting, rash, desquamation, shock, end organ failure
Increase AST and ALT, bilirubin
Prolonged use of tampons
Staphylococcus epidermidis
Gram +, catalase + coagulase - urease + cocci, novobiocin sensitive,
Does not ferment mannitol
Normal skin flora
infects prothetic devices and IV catheters
Staphylococcus saprophyticus
Gram + catalase + coagulase - rease +. Novobiocin resistant
Normal flora of female genitalis
Uncomplicated UTI
Streptococcus pneumoniae
Gram +, a hemolytic, lancet shaped diplococci, encapsulated, IgA protease, optochin sensitive, bil soluble
Meningitis, otitis media, pneumonia, sinusitis
Rusty sputum, sepsis in SCD and asplenic patients
Streptococcus viridans
Gram +, a hemolytic cocci, Optochin resistant, bile insoluble
Normal oropharynx flora
mutans and mitis –> dental caries
sanguinis –> damaged heart valves
Streptococccus pyogenes
Gram + cocci, M protein (rheumatic fever)
Pyogenic: pharyngitis, cellulitis, impetigo
Toxogenic: scarlet fever, TSST
Immunologic: rheumatic fever
Streptococcus agalactiae
Gram +, bacitracin resistant, B hemolytic. Babies
colonized vagina, causes pneumonia, meningitis and sepsis
Hippurate test + PYR-, produce CAMP factor
Streptococcus bovis
Gram +, colonizes the gut
cause bacteremia and subacute endocarditis and associated with colon cancer
Enterococci
Gram + cocci, penicillin G resistant
Normal colonic flora
cause UTI, biliary tract infection and subacute endocarditis
Catalase - PYR +
Cutaneous anthrax
painless papule surrounded by vesicles –> ulcer with black eschar –> uncommonly progress to bacteremia and death
Pulmonary Anthrax
inhalation of spores –> flu like symptoms that progress to fever, pulm hemorrhage, mediatstinitis
Bacillus cereus
Gram + rod, sores
causes food poisoning (rice)
emetic: nausea and vomiting within 1-5 hours via cerulide (preformed toxin)
Diarrhea: watery, nonbloody diarrhea and GI pain within 8-18 hours
Clostridium difficile
Gram +, spores, obligate anaerobe
Produce toxins A and B –> damage entorcytes –> water diarrhea –> pseudomembranous colitis
Toxic megacolon
Listeria monocytogenes
Gram + facultative intracellular rod
ingestion of unpasteurized dairy
Rocket tails via actin polymerization
causes amnionitis, septicemia, spontaneous abortion
meningitis in immunocompromised, neonates and older adults
self limited gastroenteritis in healthy
T(x) ampicillin
Nocardia
Gram +, long branching, aerobe, acid fast
soil
causes pulm infections in immuocompromised. cutaneous infections after trauma in immunocompromised
T(x) bactrim
Actinomyces
Gram +, long branching, anaerobe normal oral, reproductive and GI flora causes oral/facial abscesses that drain through sinus tracts, dental caries yellow sulfur granules T(x) penicillin
Mycobacteria
Gram +
tuberculosis- resistant to multiple drugs, fever, night sweats, weight loss, cough, hemoptysis. Serpentine cord
avium- causes disseminated disease in AIDS, resistant to multiple drugs
scrolfulaceum- cervical LAD in children
marinum- hand infection in aquarium handlers
Tuberculosis
+PPD if current or past infection
-PPD if no infection, sarcoidosis or HIV
Caseating granulomas with central necrosis and Langerhan giant cells
Leprosy
Mycobacterium leprae, acid fast bacilli, likes cool temperatures –> glove and stocking loss of sensation
d(x) skin biopsy or tissue PCR
Lepromatous Leprosy
presents diffusely over the skin with lion-like facies and is communicable
low cell mediated immunity with Th2 response
Lethal
T(x): clofazimine
Tuberculoid Leprosy
few hypoesthetic, hairless skin plaques
high cell mediated immunity with Th1 response and low bacterial load
T(x) dapsone and rifampin
Neisseria
Gram - diplococci
metabolize glucose and produce IgA proteases
LOS with endotoxin
Neisseria gonococci
No polysaccharide capsule, maltose acid detection, vaccine
STI
causes gonorrhea, septic arthritis, neonatal conjunctivitis, pelvic inflammatory disease, Fitz Hugh Curtis syndrome
D(x) NAT
T(x): certriaxone
Neisseria Meningococci
Polysaccharide capsule, maltose acid detection, vaccine
via resp and oral
causes petechial hemorrhages and gangrene toes, meningitis, Waterhouse Friderichsen syndrome
D(x): culture
T(x) rifampin, ciprofloxacin, ceftriaxone
Waterhouse Friderichsen Syndrome
adrenal insufficiency, fever, DIC, shock
caused by N. meningitidis
Haemophilus influenzae
Gram - rod, produce IgA protease
aerosol
causes otitis media, conjunctivitis, bronchitis, pneumonia and epiglottitis
Vaccine: type b capsular polysaccharide
T(x): amoxicillin, clavulamate, ceftriaxone
Actinebacter baumannii
Gram - aerobic, oxidase -
Resistant hospital acquired infection
cause ventilator associated pneumonia and septicemia in immunocompromised
Brucella
Gram - aerobic
ingestion of contaminated animal products
Survives in macrophages in the reticuloendothelial system
Non caseating granulomas
undulant fever, night sweats, arthralgia
t(x) doxycycline, rifampin, streptomycin
Legionella
Gram - rod Silver stain, charcoal yeast agar Ag in urine, hyponatremia aerosol (air conditioning) T(x): macrolide or quinolone Severe pneumonia, fever, GI and CNS symptoms (smokers and chronic lung disease)
Pseudomonas aeruginosa
Aerobic, motile, catalase +, gram -
Water
Pneumonia, sepsis, ecthyma gangrenosum (cutaneous necrotic lesions), UTI, DM, osteomyelitis, otitis externa, nosocomial infection, addicts, skin infection
Mucoid polysaccharide capsule
Produces phospholipase C, endotoxin (fever shock), exotoxin A (inactivate EF2), pigments
T(x): carbapenems, aminoglycosides, monobactams, polymixins, fluoroquinolones, 3rd and 4th gen cephalosporins, extended spectrum penicillin
Salmonella typhii
Gram - rods oxidase - , produce H2S, flagella, endotoxin, Vi capsule
disseminate in blood
monocytic immune response
Constipation then diarrhea
oral vaccine or IM vaccine
Typhoid fever (rose sots on abdomen, constipation, ab pain, fever, GI ulceration, hemorrhage
T(x): ceftriaxone, fluoroquinolones
All other salmonella species
Gram - rods oxidase - , produce H2S, flagella, endotoxin Poultry, eggs, pets PMN in disseminated disease via blood diarrhea no vaccine
Shigella
Gram - rod oxidase- cell to cell spread endotoxin and exotoxin PMN infiltration, M cell invasion crampy ab pain --> tenesmus, bloody stools No vaccine from fingers, flies, good, feces
Yersinia enterocolitica
Gram -
transmitted via pet feces, contaminated milk, pork
acute bloody diarrhea, pseudoappendicitis, reactive arthritis
Enteropathogenic E. Coli
Gram -
No toxin produced
adhere to apical surface, flattens villi, prevents absorption
Diarrhea (children)
Enteroinvasive E. Coli
Gram -
invade intestinal mucosa and causes necrosis and inflammation
Klebsiella
Gram - intestinal flora lobar pneumonia in alcoholics and DM when aspirated Currant jelly sputum nosocomial UTI, multidrug resistance
Campylobacter jejuni
Gram - comma shaped, oxidase +
bloody diarrhea (children)
fecal-oral
Guillain Barre syndrome and reactive arthritis
Helicobacter pylori
curved, flagella, gram -, + catalase, oxidase and urease
colonize in antrum of the stomach –> gastritis and PUD
D(x): breath test
T(x): amoxicillin, clarithromycin, PPI
Spirochetes
spiral shaped
Borrelia, leptospira, Treponema
Lymes Disease
Borrelia burgdorferi (via tick need deer)
1) erythema migrans
2) secondary dissemination, carditis, AV block, Bell palsy, migratory myalgias
3) encephalopathy chronic arthritis
T(x): doxycycline, amoxicillin, ceftriaxone
Leptospira interrogans
spirochete with hook shaped ends found in water with animal urine
Leptospirosis: flu like symptoms, myalgia, jaundice, photophobia
Weil Disease: jaundice and azotemia from liver and kidney dysfunction, fever, hemorrhage, anemia
Syphilis
Treponema pallidum. T(x) penicillin G
Primary Syphilis
painless chancre
Secondary Syphilis
maculopapular rash (palm and soles), condylomata lata, LAD, patchy hair loss Sero test: VDRL/RPR confirm with FTA-ABS
Tertiary syphilis
gummas, aortitis, neurosyphilis, Argyll Robertson pupil
broad based ataxia, Romberg +, charcot joint, stroke without HTN
Test spinal fluid with VDRL, FTA-ABS and PCR
Congenital syphilis
facial abnormalities (rhagades, snuffles, saddle nose, notched teeth, mulberry molars, short maxilla
saber shins, CNVIII deafness
Prevent: treat mom early in pregnancy
Jarisch Herxheimer reaction
flu like symptoms after antibiotics due to killed spirochetes releasing toxins
Gardenella vaginalis
gray vaginal discharge with fishy smell, nonpainful
associated with sexual activity
clue cells have stippled appearance along outer margin
D(x) amine whiff test
T(x) metronidazole or clindamycin
Chlamydiae
obligate intracellular
elementary body- enters cell via endocytosis, transforms into reticulate body
reticulate body- replicates in cell by fission
Chlamydia trachomatis- causes neonatal and follicular adult conjunctivitis, urethritis, PIDm reactive arthritis
other chlamydia- cause atypical pneumonia via aerosol
T(x): azithromycin, doxycycline
Chlamydia trachomatis Types A, B, C
chronic infection, cause blindness due to follicular conjunctivitis
Africa
Chlamydia trachomatis Types D-K
Urethritis/PID, ectopic pregnancy, neonatal pneumonia with eosinophila, neonatal conjunctivitis (birth canal)
Chlamydia trachomatis Types L1-3
Lymphogranuloma venerum- small, painless ulcers on genitals –> swollen, painful inguinal LN that ulcerate
T(x): doxycycline
Rocky Mountain spotted Fever
Rickettsia rickettsii (tick vector)
Rash starts at wrists and ankles and spreads to trunk, palm and soles
HA, fever, rash
Typhus
Rickettsia
endemic (typhi via flea) epidemic (proazekii via louse)
rash starts central and spreads out sparing palms and soles
Ehrlichiosis
Ehrlichia via tick
monocytes with morulae in cytoplasm
Anaplasmosis
Anaplasma via tick
granulocytes with morulae in cytoplasm
Q fever
Coxiella burnetti
spores via inhalation
HA, cough, influenza like, pneumonia, combo with hepatitis
Mycoplasma pneumoniae
Walking pneumonia (insidious onset, HA, nonproductive cough, patchy or diffuse interstitial infiltrate) military, recruits, prisons, college Cold agglutinins (IgM) T(x): macrolides, doxycycline or fluoroquinolone SJS in children and adolescents
Histoplasmosis
Mississippi and ohio river valleys
macrophage filled with histoplasma
Patatal/tongue ulcers, splenomegaly, pancytopenia
Blastomycosis
Eastern and central US
broad based budding
inflammatory lung disease, disseminates to bone and skin, granulomatous nodules
Coccidioidomycosis
Southwestern US Spherule filled with endospores Disseminates to skin and bone erythema nodosum or multiforme, arthralgias, meningitis Associated with dust exposure
Para coccidioidomycosis
Latin America
budding yeast with captain’s wheel
Males
Tinea
cutaneous fungal infection
Microsporum, Trichophyton, epidermophyton
Branching septate hyphae
pruritis
Tinea capitis
head scalp
LAD, alopecia, scaling
Tinea corporis
on body
enlarging erythematous scaly rings with central clearing
contact with pets
Tinea cruris
inguinal area
Tinea pedis
Interdigital, moccasin distribution or vesicular
Tinea unguium
onchomycosis in nails
Tinea versicolor
Malassezia (yeast like) degrade lipids –> acid –> inhibit tyrosinase –> hypopigmentation, hyperpigmentation or pink patches
spaghetti and meatball appearance
T(x): selenium sulfide, antifungal meds
Candida albicans
Opportunistic fungal infection
pseudohyphae and budding yeast
oral and esophageal thrush in immunocompromised, vulvovaginitis (DM), diaper rash, endocarditis (IV drug users), disseminated candidiasis, mucocutaneous
T(x) oral fluconazole, echinocandins, amphotericin B
Aspergillus fumigatus
Opportunistic fungal infection
Septate hyphae that branch at acute angle
invasive in immunocompromised
aspergillomas post TB infection
Aflotoxins –> hepatocellular carcinoma
T(x) voriconazole or echinocandins
ABPA: hypersensitivity response to Aspergillus in lung mucus. Associated with asthma and CF –> bronchiectasis and eosinophilia
Cryptococcus neoformans
Opportunistic fungal infection
Encapsulated yeast
soil, pigeon droppings
causes cryptococcosis, cryptococcal meningitis, encephalitis (soap bubble)
T(x): amphotericin B, flucytosine, fluconazole
Mucor
Opportunistic fungal infection
nonseptate hyphae branching at wide angles
DM
via inhalation of spores –> proliferate in blood vessels, penetrate cribiform plate –> enter brain
Abscess, cavernous sinus thrombosis, HA, facial pain, black necrotic eschar on face
T(x): surgery, amphotericin B, isavuconazole
Pneumocystis jirovecii
Opportunistic fungal infection
diffuse interstitial pneumonia, bilateral ground glass
AIDS
D(x): bronchoalveolar lavage
disc shaped yeast
T(x) Bactrim, pentamidine, dapsone, atovaquone
Sporothrix schenckii
Opportunistic fungal infection cigar shaped yeast vegetation via cuts pustule or ulcer nodules along draining lymphatics T(x): itraconazole or potassium iodide
Giardia lamblia
bloating, flatulence, foul smelling, fatty diarrhea
Cysts in water
T(x) metronidazole
Entamoeba histolytica
bloody diarrhea, liver abscess, RUQ pain, flask shaped ulcers
Cysts in water
Engulf RBC
T(x): metronidazole, paromomycin or iodoquinol
Crytosporidium
Severe diarrhea in AIDS
oocysts in water
T(x) nitazoxanide
Toxoplasma gondii
Immunocompetent = mono like symptoms
AIDS = brain abscess (ring enhancing lesions)
congenital = chorioetinitis, hydrocephalus, intracranial calcifications
cysts in meat
T(x) sulfadiazine, pyrimethamine
Naegleria fowleri
fatal meningoencephalitis
swim in fresh water
amoeba in CSF
T(x) amphotericin B
Trypanosoma brucei
african sleeping sickness- enlarged LN, recurring fever, coma
via Tsetse fly (painful bite)
T(x): suramin, melarsoprol
Plasmodium vivax
Malaria (fever, HA, anemia, splenomegaly) Trophozite rings form within RBC via anopheles mosquito T(x): chloroquine, primaquine 48 hour cycle, dormant in liver
Plasmodium falciparum
Malaria (fever, HA, anemia, splenomegaly)
Trophozite rings form within RBC
via anopheles mosquito
T(x): chloroquine
Severe irregular fever patterns, parasitized RBCs occluded capillaries in brain, kidney and lungs
Plasmodium malariae
Malaria (fever, HA, anemia, splenomegaly) Trophozite rings form within RBC via anopheles mosquito T(x): chloroquine 72 hour cycle
Babesia
fever, hemolytic anemia
Ixodes tick
blood smear: ring form
t(x): atovaquone and azithromycin
Trypanosoma cruzi
Chagas disease- dilated cardiomyopathy, apical atrophy, megacolon
unilateral periorbital swelling
via kissing bug (triatomine)
T(x): benznidazole, nirfurtimox
Leishmania
Visceral- spiking fevers, hepatosplenomegaly, pancytopenia cutaneous- skin ulcers via sandfly Macrophages contain amastigotes T(x): amphotericin B
Trichomonas vaginales
foul smelling, greenish discharge, itching, burning
via sex
T(x): metronidazole
Enterobius vermicularis
pinworm
anal pruritis
fecal-oral
T(x): bendazoles
Ascaris lumbricoides
obstruction of iliocecal valve, biliary obstruction, interstitial perforation, migrates from nose to mouth
fecal oral
T(x) bendazoles
Strongyloides stercoralis
GI, pulmonary and cutaneous
soil –> skin
T(x) ivermectin or bendazoles
Necator americanus
microcytic anemia by sucking blood from intestinal call
via barefoot walk on beach (skin)
T(x): bendazoles
Trichinella spiralis
cyst in striated muscle –> myositis
fever, vomiting, nausea, periorbital edema, myalgia
via undercooked meat, fecal oral
T(x): bandazoles
Trichuris trichiura
asymptomatic, loose stools, anemia, rectal prolapse in children
fecal oral
T(x): bendazoles
Toxocara canis
visceral larva migrans- migrate to blood via intestinal wall –> inflammation affecting liver, eyes, CNS, heart
fecal oral
T(x) bendazoles
Onchocerca volvulus
skin changes (decrease elastic fibers), river blindness,
via female black fly
T(x): ivermectin
loa loa
swelling in skin, worm in conjunctiva
via deer fly, horse fly, mango fly
T(x): diethylcarbamazine
Wuchereia bancrofti
Lymphatic filariasis- worm invades LN –> inflammation –> lymphedema
via female mosquito
via deer fly, horse fly, mango fly
T(x): diethylcarbamazine
Taenia solium
Intestinal tapeworm via ingestion of larvae in undercooked pork
T(x): praziquantel
Cysticercosis, neurocysticercosis via ingested eggs in food with human feces
T(x): praziquantel, albendazole
Diphyllobothrium latum
Vitamin B12 deficiency
ingestion of larvae in freshwater fish
T(x) praziquantel
Echinococcus granulosus
Hyatid cysts in liver –> anaphylaxis
ingestion of eggs in food with dog feces
T(x): albendazole
Schistosoma
mansoni- liver and spleen enlargement
haematobium- SCC of bladder and pulmonary HTN
via skin in fresh water (snails)
T(x): praziquantel
Clonorchis sinesis
Biliary tract inflammation –> pigmented gallstones
undercooked fish
T(x): praziquantel
Sarcoptes scabiei
mites burrow into stratum carneum and cause pruritis
children, crowded populations, skin to skin
T(x) permethrin cream
Pediculus humanus
blood sucking lice that cause pruritis
T(x): pyrethroids, malathion, ivermectic lotion and nit combing
Poxvirus
Linear DS DNA, envelope
Smallpox eradicated world wide via live attenuated vaccine
replicate in cytoplasm
Hepadnavirus
Circular partial DS DNA, envelope
Acute or chronic hepatitis (HBV)
Adenovirus
Linear DS DNA
febrile pharyngitis, acute hemorrhagic cysts, pneumonia, conjunctivitis, gastroenteritis, myocarditis
Papillomavirus
circular DS DNA
HPV warts, cervical cancer
Polyomavirus
circular DS DNA
JC: progressive multifocal leukoencephalopathy in HIV
BK: transplant pt –> kidney
parvovirus
Linear SS DNA aplastic crisis in SCD slapped cheek rash in children hydrops fetalis pure RBC aplasia and rheumatoid arthritis
Herpes Simplex 1
linear DS DNA, envelope
via resp, saliva
gingivostomatitis, keratoconjunctivitis, cold sores, temporal lobe encephalitis, esophagitis, erythema multiforme
latent in trigeminal ganglia
sportadic encephalitis (AMS, seizures, aphasia)
Cowdry A intranuclear eosinophilic inclusions
Herpes simplex 2
linear DS DNA, envelope STI latent in sacral ganglia viral meningitis Cowdry A intranuclear eosinophilic inclusions
Varicella- Zoster
HHV3 via respiratory encephalitis, pneumonia complication: post herpetic neuralgia Latent in DRG or trigeminal Cowdry A intranuclear eosinophilic inclusions
EBV
HHV4 via respiratory or saliva mono (fever, hepatosplenomegaly, pharyngitis, LAD Infect B cells via CD21 \+ heterphile Ab Amoxicillin--> maculopapular rash
CMV
HHV5
congenital, transfusion, sex, saliva, urine
immunocompromised - pneumonia, esophagitis, AIDS retinitis, hemorrhage, cotton wool exudate, vision loss
owl eye intranuclear inclusions
latent in mononuclear cells
Herpes 6 and 7
via saliva Roseola infantum (high fevers --> seizurs, diffuse macular rash trunk to extremities)
Kaposi
HHV8
sex
HIV and AIDS
dark plaques or nodules, GI and lungs
Reoviruses
linear multisegmented DS RNA
Coltivirus
Rotavirus- fatal diarrhea in children, villous destruction with atrophy –> decreased absorption of Na+ and loss of K+
Picornaviruses
Linear SS + RNA
poliovirus
Echovirus- aspectic meningitis
Rhinovirus- common cold, acid labile, nonenveloped
Coxsackievirus- aseptic meningitis, herpangina, hand, foot and mouth disease, myocarditis, percarditis
HAV
Hepevirus
linear SS+ RNA
Caliciviruses
Linear SS+ RNA
Norovirus- viral gastroenteritis
Flaviviruses
Linear SS+ RNA HCV Yellow fever Dengue St. Louis encephalitis West Nile- meningoencephalitis, flaccid paralysis Zika virus
Togaviruses
Linear SS+ RNA
chikaungunya virus (with dengue)
Rubella- fever, postauricular LAD, arthralgia, maculopapular rash (face to trunk) Blueberry muffin appearance in congenital
Eastern and Western equine encephalitis
Retroviruses
SS+ linear RNA
Have Reverse Transcriptase
HTLV- T cell leukemia
HIV- AIDS
Coronaviruses
Linear SS+ RNA
MERS, SARS
Orthomyxoviruses
Linear SS- RNA
influenza- contain hemagglutinin and neuraminidase. At risk for fatal bacterial superinfection. T(x) neuraminidase inhibitor
Paramyxoviruses
Linear SS- RNA (children) Surface F proteins that cause respiratory epithelial cells to fuse parainfluenza- croup RSV- bronchiolitis Measles Mumps
Rhabdovirus
Linear SS- RNA
Rabies
Filoviruses
Linear SS- RNA
Ebola- fatal
Arenaviruses
Circular SS-/+ RNA
LCMV
Lassa fever encephalitis
Bunyaviruses
Circular SS- California encephalitis Rift Valley fevers Crimean Congo hemorrhagic fever Hantavirus- hemorrhagic fever, pneumonia
Delta Virus
Circular SS-
via parenteral, sexual, perinatal
HDV requires HBV
Yellow Fever
Flavivirus
via Aedes mosquitoes
fever, black vomit, jaundice
Councilman bodies on liver biopsy
Genetic/antigenic shift
Infection of 1 cell by 2 different segmented viruses –> RNA segment reassortment –> different virus –> pandemics
Genetic/antigenic drift
random mutation in hemagglutinin or neuraminidase genes –> minor changes –> epidemics
Acute Laryngotracheobronchitis
croup (seal like barking cough)- narrow upper trachea and subglottis
can cause pulsus paradoxus
caused by parainfluenza viruses
contain hemagglutinin and neuraminidase
Measles
prodromal fever with cough, corynza, conjunctivitis –> Koplik spots –> maculopapular rash (head –> down)
Lymphadenitis with Warthin Finkeldey giant cells
Vitamin A reduce morbidity
Mumps
MMR vaccine
parotitis, orchitis, aseptic meningitis, pancreatitis
can cause sterility
Rabies
Bullet shaped
Negri bodies (cytoplasmic inclusions in Purkinje)
long incubation
Travels to CNS retrograde (dyenin) after binding ACh receptors
fever, malaise –> agitation, photophobia, hydrophobia, hypersalivation –> coma –> death
Ebola
Filovirus target endothelial cells, phagocytes, hepatocytes
abrupt flu like symptoms, diarrhea, high fever, myalgia
Can progress to DIC, diffuse hemorrhage, shock
via direct contact with bodily fluids
supportive care
Zika
Flavivirus via Aedes mosquito conjunctivitis, pyrexia, itchy rash congenital microcepahly or miscarriage Sexual and vertical transmission Supportive Care
HAV
RNA picornavirus fecal- oral (shellfish) short incubation Acute and self limiting Hepatocyte swelling, monocyte infiltration, councilman bodies No carrier state
HBV
DNA hepadnavirus via blood, sex, pernatal long incubation fever arthralgia, rash --> HCC granular eosinophilic ground glass carrier state common Aplastic anemia membranous GN > membranoproliferative GN PAN
HCV
RNA flavivirus
via blood
long incubation
may progress to cirrhosis or carcinoma
Lyphoid aggregates with focal areas of macrovesicular steatosis
carrier state very common
essential mixed cryoglobinemia, increasedrisk of B cell NHL, ITP, autoimmune hemolytic anemia
Membranoproliferative GN > membranous GN
increased risk of DM, autoimmune hypothyroidism
HEV
RNA hepevirus fecal oral short incubation fulminant hepatitis in expecting mothers patchy necrosis
Anti HAV IgM
IgM to HAV
detect acute hepatitis A
Anti HAV IgG
IgG to prior HAV or vaccination
HBsAg
Ag on surface of HBV
hepatitis B infection
Anti HBs
Ab to HBsAg
immunity to Hepatitis B via vaccination or recovery
HBcAg
Ag associated with core of HBV
Anti HBc
Ab to HBcAg
IgM- acute or recent infection (window)
IgG- prior exposure or chronic infection
Anti HBe
Ab to HbeAg
low transmissibility
HIV structure
RNA
env (gp120/41)- attach to host CD4 and fusion and entry
gag (p24/17)- capsid and matrix proteins
pol- reverse transcriptase, integrase , protease
Virus binds CD4 and CCR5 (macrophages) or CXCR4 (T cells)
HIV D(x)
HIV1/2 Ag/Ab immunoassays
Detect p24 Ag and IgG Ab
AIDS d(x): <200 CD4 or HIV+ with AIDS defining condition
Stages of untreated HIV
Flu-like (acute)
Latent- virus replicates in LN
Falling count
Final Crisis
Diseases when CD4 <500
Candida- oral thrush (scrapable white plaque, pseudohyphae)
EBV- oral hairy leukoplakia (lateral tongue)
HHV8- Kaposi
HPV- SCC (anus or cervix)
Diseases when CD4 <200
Histoplasma capsulatum- fever, weight loss, fatigue, cough, dyspnea, nausea, vomiting, diarrhea
HIV- Dementia
JC virus: progressive multifocal leukoencephalopathy
Pneumocystis jirovecii- Pneumocystis pneumonia (ground glass)
Diseases when CD4 <100
Aspergillus fumigatus- hemoptysis, pleuritic pain
Bartonella- Bacillary angiomatosis
Candida- esophagitis
CMV- colitis, retinitis, esophagitis, encephalitis, pneumonitis
Cryptococcus neoformans- Meningitis
Cryptosporidium- chronic watery diarrhea
EBV- B cell lymphoma
Mycobacterium- systemic symptoms, lymphadenitis
Toxoplasma gondii- brain abscess
Prions
Convert a helical –> B pleated via CNS related tissue or contaminated food.
Resists protease degradation and facilitates the conversion of prion
Spongiform encephalopathy, dementia, ataxia, death
CJD- rapid dementia
Bocine spongiform encephalopathy
Kuru- via human cannibalism
Pneumonia in neonates
Strep B
E coli
Pneumonia in chidren
RSV Mycoplasma C. trachomatis C pneumoniae S. pneumoniae
Pneumonia in adults
Mycoplasma
C. Pneumoniae
S. pneumoniae
Viruses
Pneumonia in older adults
S. pneumoniae H. influenza Anaerobes Viruses Mycoplasma
Pneumonia in elderly
S. pneumoniae influenza virus Anaerobes H. influenzae Gram - rods
Meningitis in Newborn
Strep B
E. coli
Listeria
Meningitis in children
S. pneumoniae N. meningitidis H influenzae B Strep B enteroviruses
Meningitis in Adults
N. meningitidis
S. pneumoniae
Enteroviruses
HSV
Meningitis in elderly
S. pneumoniae N. meningitidis H. infleunzae B Strep B Listeria
Infections causing brain absecess
Most common- viridans and s. aureus
Multiple- bacteremia
Toxoplasma gondii- AIDS
Osteomyelitis most common
S. aureus
Osteomyelitis in sexually active
N. gonorrhea, septic arthritis
Osteomyelitis in SCD
salmonella
Osteomyelitis in prosthetic joint
S. epidermidis
Osteomyelitis vertebral involvement
s. aureus, M. tuberculosis
Osteomyelitis in bat and dog bites
Pasteurella multocida
Osteomyelitis in IV drug users
S. aureus, pseudomonas, candida
UTI organisms
E. coli, Staph saprophyticus (sexually active), Klebsiella pneumoniae, serratia, enterococcus, proteus mirabilis (struvite stones), pseudomonas
D(x) Leukocyte esterase, Nitrite test (E. coli), Urease test (stap, proteus, klebsiella)
Bacterial vaginosis
No inflammation, thin white discharge, fishy odor
Clue cells basic
T(x): metronidazole or clindamycin
Trichomonas vaginitis
inflammation, frothy yellow-green foul smelling discharge
motile pear shaped, basic
T(x): Metronidazole
Candida vulvovaginitis
inflammation, thick white cottage cheese discharge Pseudohyphae T(x): Azoles
ToRCHHeS Infections
Toxoplasma gondii- chorioretinitis, hydrocephalus, intracranial calcifications +/- blueberry muffin
Rubella- abnormal eye, ear, PDA, blueberry muffin rash
CMV- hearing loss, seizures, petechial rash, blueberry muffin rash, chorioretinitis, perventricular calcifications
HIV- recurrent infections, chronic diarrhea
HSV2- meningoencephalitis, herpetic lesions
Syphilis- stillbirth, hydrops fetalis, facial abnormalitis, saber shins, CNVIII deafness
Pelvic Inflammatory Disease
Chlamydis trachomatis, Neisseria gonorrheae
Cervical motion tenderness, adnexal tenderness, purulent cervical discharge
Salpingitis, endometritis, hydrosalpinx and tubo ovarian abscess
Fitz Hugh Curtis- inflammation of liver capsule
Penicillin G and V
B lactam antibiotics
D-Ala D-Ala structural analog –> bind transpeptidase –> lock cross linking of peptidoglycan wall –> autolytic enzyme
Gram + , N. meningitidis, spirochetes
Hypersensitivity, direct Coombs + , interstitial nephritis
Penicillinase sensitive penicillins
Amoxicillin, ampicillin, aminopenicillins
D-Ala D-Ala structural analog –> bind transpeptidase –> lock cross linking of peptidoglycan wall –> autolytic enzyme
H. flu, H pylori, E coli, Listeria, proteus, salmonella, shigella, enterococci
Hypersensistivity, rash, pseudomembranous colitis
Resistance via penicillinase
Penicillinase resistant penicillin
Dicloxacilin, nafcillin, oxacillin
D-Ala D-Ala structural analog –> bind transpeptidase –> lock cross linking of peptidoglycan wall –> autolytic enzyme
S. aureus
Hypersensitivity, interstitial nephritis
Antipseudomonal penicillin
piperacillin, ticarcillin
D-Ala D-Ala structural analog –> bind transpeptidase –> lock cross linking of peptidoglycan wall –> autolytic enzyme
Pseudomonas, gam-
Hypersensitivity
Cephalosporins
inhibit cell wall synthesis. Bactericidal
Hypersensitivity reactions, autoimmune hemolytic anemia, disulfram like reaction, vit K deficiency, increase nephrotoxicity
Inactivated by cephalosporinases
1st generation cephalosporins
cefazolin cephalexin
Gram + cocci, proteus, E.coli, Klebsiella
2nd generaltion cephalosporins
cefaclor, cefoxitin, cefuroxime, cefotetan
gram + cocci, H flu, Enterobacter, Neisseria, Serratia, Proteus, E coli, Klebsiella
3rd generation cephalosporins
ceftriaxone, cefotaxime, cefpodoxime, ceftazidime
gram - infections
4th generation cephalosporins
cefepime
gram - with increased activity against pseudomonas and gram +
5th generation cephalosporins
ceftaroline
broad gram + and gram -
MRSA and enterococcus faecalis
NOT PSEUDOMONAS
B lactamase inhibitors
Clavulanic acid, avibactam, sulbactam, tazobactam
Added to penicillin Abx
Carbapenems
Doripenem, Imipenem, Meropenem, Ertapenem
Administered with cilastatin (imipenem)
gram + cocci, gram - rods
GI distress, rash, CNS tox
inactivated by carbapenemases (klebsiella, E coli and Enterobacter)
Monobactams
Azetreonam
prevent peptidoglycan cross linking by binding to PBP3.
gram - rods
nontoxic, sometimes GI upset
Vancomycin
inhibit cell wall peptidoglycan formation by binding D ala D ala
C. difficile, MRSA, S. epidermidis, etnerococcus
nephrotox, ototox, thrombophlebitis, red man syndrome, DRESS syndrome
resistance via amino acid modification
30S inhibitors
inhibit bacterial protein synthesis
aminoglycosides
tetracyclines
50 S inhibitors
inhibit bacterial protein synthesis
chloramphenicol, clindamycin,
erythromycin
linezolid
Aminoglycosides
gentamicin, neomycin, amikacin, tobramycin, streptomycin
irreverisble inhibiton of 30S
gram - rod
nephrotox, neuromuscular block, ototox, teratogenicity
Bacterial transferase enzymes inactivate the drug
Tetracyclines
tetracycline, doxycycline, minocycline bind 30S Borrelia burgdorferi, M. pneumoniae GI distress, discoloration of teeth and inhibit bone growth, photosensitivity contra: pregnant
Tigecycline
Tetracycline derivative
Bind 30S
gram -, gram +, MRSA, VRE
GI symptoms, nausea, vomiting
Chlorampenicol
block peptidyltransferase at 50 S
meningitis, rickettsia
adverse: anemia, gray baby
Clindamycin
block peptide transfer at 50 S
anaerobic infections, strep A
adverse: pseudomembranous colitis, fever, diarrhea
Linezolid
inhibit protein synthesis by binding 50 S
Gram +, MRSA, VRE
adverse: bone marrow suppression, peripheral neuropathy, 5HT syndrome
Macrolides
azithromycin, clarithromycin, erythromycin
inhibit protein synthesis by blocking translocation of 50S
Atypical pneumonias, STIs, gram + cocci, pertussis
Adverse: GI motility, arrhythmias, cholestatic hepatitis, rash, eosinophilia
Polymyxins
Colistin, B
cation polypeptides that bind phospholipids on cell membrane
MDR gram -
nephrotox, neurotox, respiratory failure
Sulfanimides
inhibit dihydropteroate synthase –> inhibit folate synthesis
gram +, gram -, nocardia
Adverse: hypersensitivity, hemolysis if G6PD deficient, nephrotox, photosensitive, SJS, kericterus
Dapsone
Similar to sulfonamides
leprosy, PCJ
Adverse: hemolysis if G6PD, methemoglobinemia, agranulocytosis
Trimethoprim
inhibit bacterial dihydrofolate reductase
combo with bactrim for UTO, shigella, salmonella, PCJ, toxoplasma
Adverse: hyperkalemia, megaloblastic anemia, leukopenia, granulocytopenia
Fluoroquinolones
-oxacin
inhibit Topo II and IV
gram - rods of GU and GI tracts, gram +, otitis externa
Adverse: GI upset, superinfections, rashes, HA, dizzy
contra in pregnant and children
Daptomycin
lipopeptide that disrupts cell membrane of gram + cocci
MRSA and VE
Adverse: myopathy, rhabdomyolysis
Metronidazole
form free radicals in bacterial cell
giardia, entamoeba, trichomonas, gardanella, anaerobes, H pylori
Adverse: disulfram like reaction with alcohol, HA metallic taste
Rifamycin
rifampin, rifabutin
inhibit DNA dependent RNA pol
Mycobacterium tuberculosis, leprosy, H flu B
Adverse: minor hepatotox, orange body fluid
Isoniazid
decrease synthesis of mycolic acids
M. tuberculosis
Adverse: hepatotox, SLE, anion gap met acidosis, vit B6 deficiency, seizures
Pyrazinamide
M tuberculosis
Adverse: Hyperuricemia, hepatotox
Ethambutol
decrease carb polymerization of mycobacterium cell wall by blocking arabinosyltransferase
M tuberculosis
adverse: optic neuropathy
Streptomycin
interfere with 30S
M tuberculosis
Adverse: tinnitus, vertigo, ataxia, nephrotox
Amphotericin B
bind ergosterol
Crytptococcus, Blastomyces, Coccidioides, Histoplasma, Candida, Mucor
Adverse: fever, chills, hypotension, nephrotox, arrhythmias, anemia, phlebitis
Nystatin
bind ergosterol
TOPICAL ONLY
swish and swallow for oral candidiasis
Flucytosine
Inhibit DNA and RNA synthesis via conversion to 5FU
systemic fungal infections
adverse: bone marrow suppression
Azoles
inhibit ergosterol synthesis by inhibiting CYP450
local and less serious systemic mycoses
Adverse: testosterone inhibition, liver dysfunction
Terbinafine
inhibit squalene epoxidase
Dermatophytoses
Adverse: GI upset, HA, hepatotox, taste disturbance
Echinocandins
-fungins
inhibit cell wall synthesis via inhibit B glucan
invasive aspergilliosis, Candida
Adverse GI upset, flushing
Griseofulvin
interfere with microtubule function, disrupts mitosis
oral treatment for superficial infections
Adverse: teratogenic, carcinogenic, confusion, HA, disulfram like reactions
Chloroquine
block detox of heme into hemozoin
plasmodial species
Adverse: retinopathy, pruritis
Oseltamivir
Zanamivir
inhibit influenza neuraminidase
Influenza A and B
Acyclovir
Famiciclovir
Valacyclovir
guanosine analog
HSV and VZV
Adverse: obstructive crystalline nephropathy, AKI
Ganciclovir
Guanosine analog
CMV
Adverse: bone marrow suppression, renal tox
Foscarnet
viral DNA/RNA pol inhibitor and HIV RTase inhibitor
CMV retinitis, HSV
Adverse: nephrotox, electrolyte abnormalities, seizures
Cidofovir
inhibit DNA pol
CMV retinitis, HSV
Adverse: nephrotox
NRTI
Treat HIV competitive inhibition of nucleotide binding to RTase and terminate DNA chain Adverse: bone suppression, peripheral neuropathy, lactic acidosis Abacavir (contra in HLA B27 pt) didanosine emtricitabine lamivusine stauvidine Tenofovir Zidovudine
NNRTI
Treat HIV Bind RTase Adverse: rash and hepatotox Delavirdine Efavirenz Nevirapine
Integrase inhibitors
Treat HIV
-tegra-
inhibit HIV genome integration
Adverse: increase CK
Protease inhibitors
Treat HIV
-navir
precent maturation of new viruses
Adverse: hyperglycemia, GI intolerance, lipodystrophy, nephrotox
Enfuvirtide
Treat HIV
bind gp 41, inhibit viral entry
Adverse: skin reaction at injection site
Maraviroc
Treat HIV
bind CCR5 on T cell –> inhibit interaction with gp120
NS5A inhibitors
Treat Hep C
-asvir
Adverse: HA, diarrhea
NS5B inhibitors
Treat Hep C
-buvir
prevent viral RNA rep
Adverse: fatigue, HA
NS3/4A inhibitors
Treat Hep C
-previr
prevent viral rep
Ribavirin
Treat Hep C
inhibit synthesis of guanine nucleotides by inhibiting IMP dehydrogenase
Adverse: hemolytic anemia, severe teratogen