medically impt bacteria Flashcards
what are the non gram staining bacteria
mycoplasma (no cell wall) and ureaplasma, (mycobacteria poorly staining), spirochetes , chlamydia, rickettsia, legionella
gram + cocci in clusters, catalase +, coagulase negative, novobiocin sensitive, catheters/shunts- biofilm producing, inf piercing,
Staph Epidermitus
gram + cocci in clusters, catalase +, coag neg, honeymoon cystitis, novobiocin resistant,
Staph Saphrolyticus
gram + cocci in clusters, catalase +, coagulase +, abscess forming, normal flora (nares)
-2ndary typical PNA, nosocomial + acute
-gastroenteritis 2-6 hr onset w/ salty food (salt resistant) and custards,canned meats, potatoe salad
acute endocarditis
-TSS: F, desquaminating rash, hypotension
-bullous impetigo- honey crust
-MCC osteomyletis (unless HbS)
Staph Aurues
- gram + cocci in chains, Beta-hemolytic, skin and throat = reservoir, bacitracin sensitive, PYR positive, streptolysin O ab
- pharyngitis: abrupt onset, tonsilar abscess
- Scarlet fever: blanching sandpaper rash w/ strawberry tongue
- impetigo: honey crusted lesions
- rheumatic fever: high ASO titer after strep inf
- M protein assoc w/ acute glomerulonephritis- pharyngitis or impetigo 2-3wk –> htn, edema, smoky urine
Strep pyogenes (group A Beta Hemolytic strep)
GBS, uti, maternal sepsis and MCC of neonatal meningitis + septicemia. gram + cocci in chains, catalase -, bacitracin resistant, camp test +
strep agalactiae (group B strep)
gram + cocci in chains, calase -, alpha hemolytic, MCC of CAP- rusty sputum lobar typical PNA, MCC ofadult meningitis- CSF many PMNs, low glucose, high protein,
MCC otitis media, tx is penecillin, blood agar
Strep Pneumoniae
gram + cocci in chain catalase -, alpha hemolytic, optochin resistant, normal flora of mouth, MCC plaque + dental caries, subacute endocarditis following dental work in those w/ preexisting cardiac abnormality like chronic rheumatic fever,
Viridians Streptococci
gram + cocci, catalase -, variable hemolysis, hydrolyzses esculin (bile esculin agar –> black), can cause UTI or biliary tract inf in elderly males, subacute bact endocarditis in elderly males following GI/GU Sx, preexisting heart valve damage.
Enterococcus Faecelis/facium (group D strep)
list of gram positive rods
Bacillus, clostridium, listeria, corynebacterium, actinomyces, nocardia, mycobaterium
gram + rod, aerobic spore forming, cow hide or soil w/ clow feces, biowarfare
can cause ulceroglandular inf w/ eschar-MC
inhalation of spores causes deadly PNA w/ mediastinal hemmorrhagic lymphadenitis = wool sorters disease. GI inf rare
Bacillus Anthracis
gram + rod, spore forming, aerobic, rapid onset nonbloody self-limiting Gastroenteritis, foodborne - fried rice
Bacilus cereus
gram + rod, anaerobe, spore forming, dirty puncture wounds- IVDA or environmental contaminated soil. tc w/ toxoid vaccine and passive IgG. CP: rigid paralysis, opisthotonus, risus sardonicsus. requires low tissue oxygenation. toxin retrograde axonal transport to CNS, inhibits GABA and glycine
clostridium tetani
gram + rod, spore forming anaerobe, alkaline canned vegetables/meat, reversible flaccid paralysis, honey in neonates- floopy baby syndrome, inhib Ach in peripheral nerves
Clostridium botolinum
gram + rod, spore forming anaerobe, stormy fermation on milk media environmental, contaminated wound –> inf muscle –> feathered appearance on x-ray from gas (lechithinase- alpha toxin of phospholipase C disrupts mb –> massive hemolysis, tissue destruction and hepatotox, (id w naglar reaction egg yolg), pain unproportional to wound appearance- tense tissue w. exudate, bronze to black, tachycardia disproprtionate to fever
reheated meats –> non inflamatory diarrhea
clostridium perforingens
gram + rod, spore forming anaerobe, inf of inpatient on abx- clidamycin, cephalosporitis, colitis, pseudomembranous colitis –> diarrhea, culture not diagnostic bc its normal flora- stool exam for toxin, tx: metronidazole
C diff
gram + rod, beta hemolytic, cold growth tumbling motility, reservoir- GI/GU of animals= zoonosis, facultative intracellular, tfood-borne, (deli meat bad for pregnant bc transplancental inf –> granulomatosis infantiseptica, or neonatal meningitis- 3rd MCC (after GBS and E. coli)
MCC of meningitis in renal transplant or cancer pt
Listeria monocytogenes
gram + bacillus, form gray-black colony of club shaped gram + rods V or L shape, diptheria toxin from bacterial phage ribosylates eEF-2 to inhib prot synth, gray shaggy pseudoMb in pharynx –> airway obstruction + bull neck, myocarditis , and nerve palsy- recurrent laryngeal, organism restricted to resp track (noninvasive), granules (voluntine) on loefler coag serium
Cornyeobacterium diptheriae (note: diptheroids are normal flora- dont have lysogeny aka toxin produced by a phage)
gram + rod, anaerobe, non-acid fast branching rods (acid fast branching rods = nocardia)
normal flora of gingival crevices(mycetoma) and vaginal (iud). branching rods are sulfur producing- yellow lesion post dental work,
mycetoma on jaw line or spread from IUD.
actinomyces isreali
gram + filamentous bacteria- branch like fungal hyphae but bacteria, aerobic, partially acid fast (some areas stain w/ methylene blue and others w/ carbylofushin, remember noCARDia has CORD factor)
-immunosupr/cancer
nocardosis- cavitary bronchopulmonary dz (can b acute or chronic -PNA w/ cavitation)–> brain abscess
mycetomas (subQ abscess draining granules and cellulitis)
Nocarcia asteroides and Nocardia brasiliensis
facultative intracellular, obligate aerobe, slow growing, produces niacin B3, heat sensitive-catalase (catalse neg in lab test but catalase + in body temp), aureamine-rhodamine staining- flourescent apple green - sensitive not specific, confirm w/ AFB.
-sulfatides in cell envelope- inhib phagosome-lysosome fusion
-cord factor (trehalose dimycolate)- serpentine growth, inhib mito resp + oxphos, inhib leukocye migration
-tuberculin surface prot and mycolic acid –> cause T4 HSR
Gohn complex- kill macrophage –> abscess + regional lympht node
reactives
matoux = PDD test- exposure not dz vaccine
vaccine BGC
quantiferon test- disease
rifamin, izoniazid,
Mycobacterium
MAC/MAI. M. kansasi - TB w/ aids (pulm/GI/dissem inf)
M. scrofulatum- scrofula(cervical lymphadenitis) in peds
m. Marinum- fish tank granuloma
MOTS (myocabacterium other than TB)
immigrant pt w/ sensory loss in extremities –> acid fast rods in punch biopsy
hansons disease, slow replicating, intracellular, inf endothelial cell, schwann cell, and langerhans cell stays in peripheral (growth at 33deg), obligate intracelular
acid fast stain, PPD only + in lepromatous leprosy
dapsone
mycobacter Leprae
weakly gram staining (gram -), diplococci w/ flattened sides in neutrophils. PID, urethritis, acute prostatitis, septic arthritis (knee), oxidase + (enterobactericae group oxidsase -), genital portal of entry (sexually active pt), luekorrhea (dishcharge), neonatal opthalmia
ferments glucose
Niesseria Gonorrhiae
gram - diplococcus in CSF, oxidase positive, ferments maltose and glucose, young adult w/ meningitis (dorm room), acute fulminant meningiti w/ signs of endotoxin (LPS) toxicity
Nieseria meningitis
encapsulated organisms inc: e. coli, strep pna, salmonelli typhi, klebsiella pna, haemophilus inf typable, pseudamonus, bordatella/bacteriodies, crypto
even some super killers have pretty nice big capsules
gram - encapsulated rod, oxidase positive, aerobic (nonfermenting), ubiqitous in water/IV/contact soln nosocomial,blue green flourescence filamentous (pyocyanin), burn inf–> green/fruity odor, slime layer, UTi w/ catherlization, typical PNA- (w/ sempticiemia) CGD or CYSTIC FIBROSIS. healthy people: loose stool, hottub folliculitis, corneal ulceration,
sources of in: raw veg, respirators, humidificers, sink drains, potteed or cut flowers, whirlpools.
intrinsic and acquired sensitivity - must antibiotic sensitivity test before and during tx
pseudamonas aeringuosa
weakly gram -, pleomorphic rods requiring cysteine and iron, water HVAC tanks, facultative intracellular, seroconversion, pontiac dz, or legionarres disease (smoker, EtOH, immunosupressed), endotoxin. atypical PNA w/ confusion and diarrhea
Legionella pneumophillia
zoonotic, gram neg sm rod, facultative intracellular, biowarfare risk, cysteine required for growth. rabbit hide (deer licks) (trappers disease), arkansas missouri, ulceroglandular disease via tick bite- ulcer w/ eschar regional LAD, gastroenteritis, fatal atypical PNA if aerosolized,
Francisella tularensis
encapsulated, unvaccinated child, whooping cough, filamentous hemagluttingin (attachment) , pertusus toxin ADP ribosylation of Gi, stays in resp track, 100 day cough, AC toxin, tracheal cytotin, vacine need booster - IgA mediated since its mucosal inf, vaccinated human as reservoir, afebrile adult w/ cough for 2+ wk. DTaP
Bordetella pertusis
zoonosis exposure to animal or unpasturized dairy, many manifestations pt w/ acute septicemia. cali/texas/mexico. biowarfare potential,
Brucella (abortus, millensus, suis)
from vertebrate –> human. brucella, francisella, campylobacter, listeria monocytogenous, salmonella enteritidis, yersinia pestis, chlamydophillia psittaci,
zoonotic organisms
watery, enterotoxin destroys water and electrolyte fxn of mucosal cells w/out damage to structure of the cell --> inflammation. organisms remain in lumen -vibrio cholerae (rice water stool) -ETEC (e coli) bacillus ceraeus C diff
noninflam diarrhea and bacterial causes
cell death, invasion of bacteria, blood/mucous in stool salmonella campylobacter jejuni C diff shigella enterohemorrhagic e coli enantomeba histiolytica
inflammatory diarrhea and bacterial causes
inflam D, gram -, curved rod w/ polar flagella (“gulls wings”), oxidase -, grows at 42, microaerophillic
dz: gastrenteritis, MC inf diarrhea workwide, 10+ stools a day w/ blood
complications: Guillane barre syndrome, reactive arthtiris
campylobacter jejuni
gram - helical bacilli, urease positive (can make ammonia to survive pH of stomach), gastritis- pud, assoc w/ gastric adenocarcinoma and low grade lymphoma.
H pylori
gram - rod w/ polar flagella, oxidase +, alkaline growth TCBS media, non inflam rice stool diarrhea, hydrate and replace electrolytes to prevent fatal dehyration, travel to endemic area, cholera enteroticin ADP ribosylates Gs –> AC activation –> cAMP –> efflux of Cl- and h2o (simular to e coli labile toxin LT)
(two other vibrio species and V. paraheaemolyticus - gastroenteritis raw seakfood, V. vulnificus oysters- gastroenteritis or cellulitis (swimming)
vibrio cholerae
gram neg bacilli, oxidase negative, nitrates –> nitritries, catalase +. lactose fermenting (pink colony) or nonlactose fermenting (clear colony + divided into H2S producing or nah)
enterobacteriacae family
