Term
General staphylocci characteristics |
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Definition
- Gram +
- catalase +
- clusters
- mainly extracellular
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Term
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Definition
Protein A is a major cell component of S. auerus; anti-phagocytic;
latex agglutination assay is diagnostic.
Protein A binds nonspecifically to Fc region of particular isotypes of IgG. |
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Term
How is teichoic acid used by S. aureus? |
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Definition
Attachment to fibronectin-coated surfaces; inflammation |
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Term
How is catalase used? Who is susceptible? |
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Definition
differentiate staph from strep; Chronic granulomatous disease |
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Term
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Definition
differentiate staph aureus from other staph |
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Term
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Definition
Staph exotoxin; superAg; induces TNF and IL-1; causes shock, fever, rash desquamation of skin, diarrhea (Food poisoning+diarrhea) |
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Term
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Definition
resistant to boiling, emesis and diarrhea |
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Term
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Definition
staph exotoxins; proteases breakdown bonds between keratinocytes -desmoglein-1 no longer maintains Keratin-Keratin attachment; SSSS, scarlet fever, bullous impetigo. |
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Term
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Definition
Gram, beta-hemolytic on BAP with golden color (coag negative staph are white);
Coagulase and Protein A used to identify in RLAT |
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Term
Clinical manifestations of Staph infections |
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Definition
Cutaneous - Boils (furuncles), carbuncles, folliculitis, styes, paronychia, bullous impetigo, SSSS;
Burns/wounds- nearly all wounds are staph or P.aeruginosa, polymicrobic
UTI - s. sapro ascends; Pneumonia 2ndary to viral RT- consider in CF patients due to immunocompromised
Bact/Sept, osteomyelitis (MCCO), pyelonephritis, endocarditis, meningitis - usually spread from a skin infection;
StahphTSS
Food Poisoning -intoxication not infection, 2-6hr onset, violent vomiting |
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Term
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Definition
- Meth/naf/ox if sensitive
- MRSA=IV Vanc, linezolid, synercid, daptomycin
- Penicillin is not effective
- Sensitivity testing is important
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Term
Staph epidermidis - General characteristics |
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Definition
Coag-negative;low virulence; MCCO prosthetic heart valve infection;
Meth resistance = difficult to treat;
MCCO nosocomial bacteremia. |
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Term
Where do S. epidermidis infections occur |
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Definition
- foreign bodies (prostheses, IV cath, shunts - MCCO these infections d/t slime layer)
- only slime layers infect prostheses
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Term
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Definition
Coag negative; normal flora, esp skin and periurethral
community acquired UTI, distant 2nd to E. coli among outpatient UTI;
S/S of uncomplicated cystitis - suprapubic pain, dysuria (burn), frequency/urgency, bacteuria (greater than 10^5, if < consider STI) |
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Term
Streptococcus - general profile |
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Definition
Gram + catatase negative; high maintenance growth requirements, but does well on BAP |
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Term
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Definition
part of cell wall of strep; All pyogenics are typable, not all types are pyogenic;
S. pyo is GAS;
S. agalactiae is GBS;
E.feacalis, E.faecium are GDS;
S. pneumoniae = non-typable alpha-hemolytic (viridans is also non-typable alpha) |
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Term
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Definition
S. pneumonia - mulitple carbo types
s.pyogenes - hyaluronic acid;
GBS - several contain sialic acid (vaccines in trial) |
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Term
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Definition
Beta - complete, GAS, GBS, others
Alpha -incomplete (greening), s. pneumonia, viridans
Non- GDS are non-hemolytic |
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Term
Source of strep infections |
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Definition
Humans; endogenous and exogenous. |
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Term
S. pyogenes (GAS) - virulence factors |
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Definition
Fimbriae/fibrillae composed of M Protein + LTA; strep pyrogenic exotoxins (SPEs); hemolysins- SLO; hemolytic enzymes |
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Term
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Definition
Strep virulence factor; strongly antiphagocytic; anti-M abs protect against strep but multiple types exist; cross react with human heart tissue - possible contributor to ARhF; LTA is adhesin associated with M. |
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Term
Streptcoccal pyrogenic exotoxins (SPE) |
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Definition
- Pyrogens/superAgs
- Scarlet fever
- STSS
- Necrotizing fasciitis/myositis
- SPEs are FERST
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Term
S.pyo diagnostic for ARhF |
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Definition
SLO - anti-SLO abs is diagnostic for ARF; |
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Term
Lab dx of strep pyogenes (GAS) |
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Definition
Beta-hemolytic, G+cocci in chains, Catalase negative, Bacitracin sensitive (B-BRAS) ; Definitive lab dx- lancefield (GAS) RADT |
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Term
where is S.pyo reservoir? |
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Definition
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Term
Non-invasive GAS diseases |
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Definition
Pharyngitis. ScarletFever. Skin infections -impetigo, erysipelas, cellulitis |
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Term
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Definition
Septicemia, Toxic Strep Syndrome, necrotizing fasciitis and myositis |
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Term
Non-suppurative diseases from strep |
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Definition
ARhF, Acute Glomerulonephritis (AGN), E. nodosum |
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Term
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Definition
2-3wks post strep throat, not skin; Dx is strengthened by proven strep throat, high anti-SLO titer; prompt abx (Pen V) for strep throat can prevent |
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Term
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Definition
follow strep pharyngitis or strep skin infection, immune complex disease |
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Term
S. agalactiae (GBS) characteristics |
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Definition
Beta-hemolytic, bacitracin resistant (B-BRAS), antiphagocytic capsules contain sialic acid, colonize vagina during pregnancy |
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Term
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Definition
antiphagocytic capsules, if mother makes Ab neonate is protected; Chance of neonatal infection increases with prematurity and prolonged labor. Culture mom @ wk 35-37 and administer intrapartum Abx (Pen/Amp) |
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Term
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Definition
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Term
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Definition
Neonate sepsis, menigitis, respiratory disease; Soft tissue infections, septicemia, endocarditis in compromised adults (diabetics, AIDS, cardiodisease, immunocompromised) |
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Term
Enterococcus - Class and characteristics |
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Definition
GDS, bile-esculin +, NaCl tolerant, opportunistic endogenous source of infection, Pen/Ceph natural resistance, some strains are VRE. One of the most resistant bugs. |
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Term
Opportunistic disease from Enteroccocus |
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Definition
Nosocomial UTI or septicemia, Subacute endocarditis (SBE), esp valvular heart disease |
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Term
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Definition
Inhibit peptidoglycan crosslink, Gram+ only, Resistance in staph is from Enterococcus but VRSA is rare; Tx entero infections, serious MRSA, pneumoccocal meningitis when PenR is prevalent (empiric prior to known sensitivity), C. difficile |
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Term
How to treat VancR strains for Enterococcus |
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Definition
IV Linezolid, Synercid, daptomycin |
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Term
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Definition
Nontypable, Alpha hemolytic strep, normal in pharyngeal/oral, opportunist, leading cause of SBE (look for damaged valves), Prophy Abx if damaged valves, murmurs for dental procedures; S. mutans has slimy sucrose capsule that attaches to teeth |
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Term
S. pneumoniae characteristics |
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Definition
Non-groupable alpha hemolytic; lancet shaped diplococci, Optochin-sensitive, bile soluble (OVPRS-distinguish Strep pneumo from viridans); |
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Term
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Definition
Capsule (80 types) - anti-phagocytic, abs are protective, RATDs detect capsule Ag in sputum, CSF, blood, urine; Pneumolysin; surface protein; C-substance-binds CRP > synthesis of acute phase reactants |
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Term
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Definition
Culture sputum, blood CSF (Ab sensitivity needed); gram stain of above, RADTs |
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Term
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Definition
- MOPS!!!
- Meningitis (MCCO bacterial meningitis in adults/children)
- Pneumonia,
- URTI (Otitis media, sinusitis)
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Term
Risk factors of S. pneumoniae pneumonia |
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Definition
- Viral infections (flu, milder RTI),
- Chronic pulmonary disease,
- splenic disorders (sickle cell, diabetics),
- EtOH abuse
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Term
Classic pneumoccal pneumonia |
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Definition
Single rigor (shaking chill) rusty sputum, pleuritic pain, fever, lobar pneumonia/consolidation on CXR, lungs fill with fluid due to immune rxn |
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Term
Treatment for pneumoccocal pneumonia |
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Definition
AbxR is a consideration - order sensitivities for all isolates; Penicillin or ceftriaxone; If PenR use fluoroquinone (ie levofloxacin, fluoroquinone |
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Term
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Definition
S. pneumoniae, H. influenzae, M. catarrhalis |
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Term
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Definition
headache, neck stiffness, fever, vomiting, photophobia, irritability, neuro dysfunction |
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Term
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Definition
usually associated with large #s of PMN, decreased glc, increased protein |
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Term
Identification of bacterial agent causing meningitis |
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Definition
- Gram stain CSF,
- Culture CSF and Blood (CAP/BAP)
- sensitivities
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Term
Treatment of pneumococcal meningitis |
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Definition
Pen/Ceph resisitance common in Memphis;Tx with Ceph+Vanc combo |
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Term
Pneumococcal meningitis vaccine |
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Definition
Pneumovax (multivalent, not conjugated, 23capsule types) - over 65, high risk, 5-7yrs resistance; Prevnar - safe and $$$$, abs seen in children @ 2 mos (young!), anamnestic response |
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Term
Neisseria meningitidis - general |
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Definition
Gram negative, kidney bean, oxidase positive, diplococci |
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Term
Neisseria meningitidis - virulence |
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Definition
Polysaccharide capsule is antiphagocytic and basis for polvalent vaccine; C6 deficiency is a risk |
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Term
Neisseria meningitidis (meningococcal) diseases |
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Definition
- Meningitis to bacteremia
- Petechial to frankly purpuric skin rash in meningococcemia
- meningococcemia is rare and deadly
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Term
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Definition
Pen, ceftoxamine, ceftriaxone; only minor resistance problems |
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Term
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Definition
Vaccine but not for Group B serotype, reccomended for all children @ 11-12yrs; Abx prophy (Cifprofloxacin or Rifampin) |
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Term
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Definition
disease/infection mirrors S. pneumo; Small non-motile G- rod; grows on CAP, not BAP |
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Term
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Definition
Encapsultated (type b and f)- severe, systemic disease; HIB is invasive, polyribotol capsule is antiphagocytic; Unencapsulated strains - chronic resp disease in elderly, sinusitis, Otitis media, conjunctivitis in kids/infants. Peumonia also possible |
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Term
H. influenzae -tx and prevention of disease |
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Definition
3rd gen CEPH with dex prior to abx; Conjugated type b vaccine is part of infant-childhood vaccination series |
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Term
Listeria monocytogenes - general |
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Definition
facultative intracellular parasite; infects mucosal epithelial cells and non immune macs/monos; Foodborne- meats/cheeses, uncommon but high mortality |
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Term
Listeria monocytogenes - diseases |
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Definition
Infections resemble flu, preggers 20x more likely; Bacteremia,meningitis in compromised and neonates |
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Term
Tx of bacterial meningitis |
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Definition
- 3rd gen ceph, add ampicillin if listeria is suspected.
- If resistant S. pneumo (MCCO) is possible add vanc.
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Term
Panton-Valentine leukocidin |
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Definition
Cytolytic toxin used by Staph aureus; found in most community acquired MRSA |
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Term
Review of bacterial heart infections |
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Definition
Aureus= ACUTE bacterial endocarditis; Virdans (S. mutans) & GDS (entero) = SBE. Virdans is leading cause of SBE
ARhF is caused by S. Pyogenes and can lead to bacterial endocarditis by damaging valves. |
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