STAPHYLOCOCCUS AUREUS, THE GOLDEN CHILDNeil Goodloe, MD Cox Health ID
INTRODUCTIONS
! Staphylococcus is a gram positive organism ! Distinguished from Streptococcal species by
clusters versus chains on Gram stain ! 2 different catagories of Staphylococcal
organisms ! S. aureus ! Coag Negative Staph, can cause certain invasive
infections
INTRODUCTIONS INTRODUCTIONS
INTRODUCTIONS INTRODUCTIONS
! Mannitol-salt agar, is chemically-configured to turn yellow when S. aureus ferments the mannitol,changing the color of the phenol red indicator dye.
INTRODUCTIONS
! This is example of an antibiotic sensitivity test. The size of the “inhibition zones" depends on the sensitivity of the bacteria.
INTRODUCTIONS
WHAT AND WHY OF STAPHYLOCOCCUS AUREUS.
! It is now #1 for Native and prosthetic valve bacterial endocarditis.
! The types of infections are very broad ! Blood stream infections ! Skin and soft tissue infections
! Device infections
! Toxin mediated illnesses ! Community outbreaks
ANTI-STAPH ANTIBIOTICS
! Anti –staph penicillins ! Nafcillin, oxacillin, dicloxacillin
! Not active for anaerobes, enterococcus, Gram negatives or listeria
ANTI-STAPH ANTIBIOTICS
! Aminopenicillins ! Ampicillin and Amoxicillin
! Strep. pneumo, Prot mirabilis, many gonococci & meningococci & Clostid
! Amoxicillin – clavanutate (Augmentin)
! As for amoxicillin & also Staph. ! H influenzae, B fragilis & other anaerobes, E
coli, salmonella & shigella ! Among gram-positive bacteria, staphylococci are
the major pathogens that produce β-lactamase
ANTI-STAPH ANTIBIOTICS
Ceph Gen 1st 2nd 3rd 4th 5th S. aureus +++ ++ + + + MRSA - - - - + ! Of Course Vancomycin, Daptomycin,
Dalbavancin, Oritivancin, Linezolid, Tedezolid all also cover MRSA infections as well.
! Sulfa, Lincomycins, Tetracyclines are dependent on susceptibilities
! Ceftaroline is 5th gen cephalosporin
STAPHYLOCOCCUS AUREUS BACTEREMIA.
! Blood stream infections ! Complicated or uncomplicated? ! Additional blood culture
! NEVER consider a contaminate
! As apposed to Coag Negative Staphylococcus
! With an exclusion later ! Echo is recommended for all adult patients
UNCOMPLICATED BACTEREMIA.
! Positive blood culture results and the following: ! exclusion of endocarditis ! no implanted prostheses ! follow-up blood cultures performed 2–4 days
after the initial set that do not grow ! Defervescence within 72 h of initiating
effective therapy ! No evidence of metastatic sites of infection
! 2weeks of treatment
COMPLICATED BACTEREMIA STAPHYLOCOCCUS AUREUS
! Patients with positive blood culture results who do not meet criteria for uncomplicated bacteremia
! Increased risk ! Community acquired ! Fever >72 hours ! Repeat blood culture positive ! Any device
! 4-6 weeks of treatment ! Think about the source too!
COMPLICATED BACTEREMIA STAPHYLOCOCCUS AUREUS
! Risk ! 12% for Native valves ! 40% for Prosthetic valves ! Can not rule out BE by exam with
Staphylococcus aureus ! TEE is preferred method
! Staphylococcus lugdunensis, be aware and beware of this one
ILLUSTRATIVE CASE
! 48yo male ! Hypotensive SBP< 90 ! HR>120 ! Confusion, Lethargy ! Fever 103 ! Rhonchi bilaterally ! Murmur along LLSB
ILLUSTRATIVE CASE
ILLUSTRATIVE CASE ILLUSTRATIVE CASE
ILLUSTRATIVE CASE
! Uncomplicated versus Complicated? ! What do you want to do? ! What else do you want to know? ! What antibiotics do you want to give?
! Think of why, what you want to cover.
ILLUSTRATIVE CASE
! WBC 30,000 ! HGB 12 ! Platelet 130,000 ! NA 132 ! CRT 1.2 ! Blood culture GPC in clusters
! Does this change your plan?
ILLUSTRATIVE CASE
! TTE Large 1.0 MV lesion ! Blood cultures finally negative on day 3 ! Fever on going for 7 days ! CXR with septic pulmonary emboli ! Culture grew MRSA ! Vancomycin IV given ! Eventually met a friendly neighborhood CTS ! UDS with Meth and Amphetamines
STAPHYLOCOCCUS AUREUS SKIN AND SOFT TISSUE INFECTIONS (SSTI)
! Skin and soft tissue infection ! We have all seen this one at least once. ! Can be very problematic in the outpatient setting ! Can lead to severe invasive infections ! Of course can be recurrent and effect everyone
in the house. ! Can be spread in a community
STAPHYLOCOCCUS AUREUS SSTI
! MRSA USA 300, an epidemiologic tracking device ! Clonal propagation from a strain that
appeared in 1995 ! Recent article showed the close relatedness
of strains being spread in Manhattan 2004-9 ! National Acad Sci USA 2014 May
6;111:6738
ILLUSTRATIVE CASE
! Recently a 9yo with a MRSA skin lesion on her back !Family attempted to express the infection
!The child presented 1 week later prostrate with fever 101
!Severe back pain
!Epidural abscess found
ILLUSTRATIVE CASE STAPHYLOCOCCUS AUREUS SSTI
! For a cutaneous abscess, incision and drainage is the primary treatment
! For simple abscesses or boils, incision and drainage alone is likely to be adequate
! Antibiotic therapy is recommended for !severe disease
!Rapid progression with cellulitis, systemic illness
!comorbidities !abscess difficult to drain !septic phlebitis !lack of response to incision and drainage
STAPHYLOCOCCUS AUREUS SSTI
! For purulent lesion empirical therapy for CA-MRSA is ! Five to 10 days of therapy is recommended
! Oral antibiotic ! Clindamycin (D-test and Erythromycin) ! Trimethoprim-sulfamethoxazole ! Tetracyclline, Oxazolidinones, Glycopeptides
! MSSA best treatment is beta-lactam (not amoxicillin) ! Use of rifampin as a single agent not recommended
RECURRENT STAPHYLOCOCCUS AUREUS SSTI.
! Decolonization does it Work? ! Hygiene and decreasing risk of exposure
!Walmart, Bathrooms, Gas stations etc ! Life span of Staph on surface? ! Household contacts? ! Animals? See Emerg Infect Disease 2007;13:1834 ! Recent article in CID 2014, June 1;58:1540 on this topic ! See IDSA Guidelines on MRSA treatment
RECURRENT STAPHYLOCOCCUS AUREUS SSTI.
! Article to look at ! New England Journal Medicine 2010;362:9-17 ! New England Journal Medicine 2013;368:533-42 ! New England Journal Medicine 2013;638:2255-65 ! Clinical Infectious Disease 2014 June;58:1540
STAPHYLOCOCCUS AUREUS PNEUMONIA
! Suspect for hospitalized patients with severe CAP ! ICU admission ! Necrotizing or cavitary infiltrates ! Empyema ! Beta lactam for MSSA
STAPHYLOCOCCUS AUREUS PNEUMONIA
! Initial choice of treatment is IV vancomycin for MRSA ! Watch MIC to vancomycin in MRSA strain ! Linezolid 600 mg PO/IV twice daily ! Clindamycin 600 mg PO/IV 3 times daily ! Ceftaroline 600mg IV Q12 hours ! Don’t use Daptomycin
STAPHYLOCOCCUS AUREUS PNEUMONIA
! MSSA treatment of choice is beta-lactam (not amoxicillin)
! 7–21 days, depending on the extent of infection ! Check Flu PCR of sputum as well in the right season ! Remember Staphylococcus produces 208
different toxins ! Tissue destruction is name of game
ILLUSTRATIVE CASE
! 65 yo female admitted for right knee pain. ! Acute onset 3 days ago ! Associated fever 102, WBC 14,000 ! PMHX: Right prosthetic joint replacement 2 years
ago. ! What do you think is wrong? ! What is your next step?
ILLUSTRATIVE CASE
! Arthrocentesis 50,000 WBC, 98% neutrophils ! Gram stain with GPC in clusters ! Now what?
ILLUSTRATIVE CASE
! She reports a PCN allergy when she was 5. ! Does this change your plan?
PCN ALLERGY
! PCN versus Cephalosporin drug reaction ! General understanding is around 10-15% risk of
cross reactivity ! New information is constantly changing ! Recently in J Emerg Med. 2012 May;42(5):612-20.
literature review showed a 1% risk in dissimilar medications.
! Always feel free to ask an ID or pharmacist.
ILLUSTRATIVE CASE
! Bacterial culture grows Staphylococcal aureus. ! What if it is Oxacillin susceptible? ! What if it was Oxacillin resistant? What does this
mean for your treatment? ! You place her on the right antibiotics and then
call your friendly Orthopedic surgeon and Infectious Disease doctor.
STAPHYLOCOCCUS AUREUS BONE AND JOINT INFECTIONS
! Surgical debridement and drainage of associated soft tissue, abscesses is the mainstay of therapy
! Optimal route of administration not established. ! Parenteral, oral, or initial IV followed by oral?
! Ancef and Nafcillin are choice for MSSA ! Call a friendly Orthopedic surgeon and Infectious
disease doctor for help. ! Prosthetic joint infections require unique treatment
decisions ! Single or 2 stage?
STAPHYLOCOCCUS AUREUS BONE AND JOINT INFECTIONS
! MRSA ! IV Vancomycin ! IV Daptomycin ! TMP-SMX BID
! Oxazolidinones, with caveats. ! Clindamycin ! Not Tigecycline or Glycopeptides at this time ! Rifampin, please call Infectious Disease prior, never
use alone, ! Remember drug-drug interactions
STAPHYLOCOCCUS AUREUS CNS INFECTIONS
! REMOVE infection! ! REMOVE Devices as able! ! Treat with Vanco for MRSA ! Nafcillin for MSSA ( Ancef?) ! Duration is variable ! If using alternative agents, talk to your
neighborhood ID doctor, it really is Complex. ! Remember blood brain barrier exists for a reason
THINGS TO REMEMBER ABOUT STAPHYLOCOCCUS AUREUS.
! Beta-lactam for MSSA ! Vanco for MRSA
! Watch Renal function and Trough ! 10-15 or >15 trough
! Watch MIC for Vancomycin, beware and be aware ! Talk to your Friendly ID doctor
! Daptomycin has limitations ! Not for lungs ! Monitor CK
THINGS TO REMEMBER ABOUT STAPHYLOCOCCUS AUREUS
! Watch Erythromycin sensitivity ! This is important for use of Clindamycin ! D-test will help resolve
! Linezolid has its place, Tedezolid has its place ! Duration of treatment increases neurotoxicity,
not recoverable, it is a mitochondrial toxicity ! Fluoroquinolones and Tetracyclines work in adults,
fearful in children ! Glycopeptides have a place too.
SCARY THINGS TO THINK ABOUT
! Antibiotic resistance genes are Ubiquitous in Soil Microorganism ! Nature 2014 May 29;509:612
! TheCost of Surgical Site Infections ! Jama 2014, May 21
! Can animals carry Staphylococcus aureus infection? ! Drug resistance can occur on treatment, even
appropriate treatment. ! Quorum sensing does exist, bacterial burden of infection
does matter.
THANKS
! See the IDSA practice guidelines for complete information contained in this Lecture
! Some pictures obtained from Open source and CDC I do not own those images.
STAPHYLOCOCCUS LUGDUNENSIS
! Community acquired infections ! Coag negative staphylococcus organism ! Almost never a contaminant ! Causes staphylococcus aureus type infections ! Hardware ! Blood ! Surgery and Mortality risk ! Oxacillin susceptible though