Antibiotic Resistance in O.M.

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Antibiotic Resistance in O.M.

• Joseph Lopreiato MD,MPH
• Associate Professor of Pediatrics
• Uniformed Services University
• of the Health Sciences
• Bethesda, MD
• Nov 1999

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Antibiotic Resistance in O.M.

• Doctors are men who prescribe medicines of which
  they know little to cure diseases of which they
  know less in human beings of whom they know
  nothing - Voltaire

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Antibiotic Resistance in O.M.

• Case 1 A 9 month old infant has a chief
  complaint of fever and fussiness since last PM.
  She has had a URI for the last several days, but
  has otherwise been well. PMH is significant for
  OM at age 6 months and day care attendance. After
  examination, you diagnosis AOM and prescribe
  Amoxicillin. After 3 days, the patient returns
  with persistent fever to 101 and fussiness. On
  exam you note that the TM is still erythematous
  and bulging. What do you do next??

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Antibiotic Resistance in O.M.

• Case 2 A 24 month old child comes into your
  office for a routine health maintenance visit. He
  has been well and has had no significant PMH. On
  examination you note a right TM that is dull and
  has decreased mobility. The child has not had any
  significant symptoms. What would you do next??

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Antibiotic Resistance in O.M.

• Organisms in Otitis Media
• Pneumococcus 35 of cases
• Haemophilus Influenza 30 of cases
• Moraxella Catarrhalis 10 of cases
• Virus 33 of cases
• Staph species
• Strep species
• Mycoplasma

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Antibiotic Resistance in O.M.

• Whats causing resistant bacteria??
• many more kids in daycare
• increased use of antibiotics, especially broad
  spectrum agents
• incomplete courses of therapy
• Inappropriate therapy (for OME)

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Antibiotic Resistance in O.M.

• Resistance seems to be correlated with
• Use of any antibiotic in the past 3 months
• White race
• Higher SES
• Day care attendance
• J Pediatr 128757. 1996

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Antibiotic Resistance in O.M.

• Antibiotic use is on the rise. In 1996,
  percentage of times that antibiotics were
  prescribed for children
• 34 to patients with a cold
• 38 for other URIs
• 52 for patients with bronchitis
• JAMA 279875. 1998

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Antibiotic Resistance in O.M.

• Mechanisms of resistance
• Microorganism produces an enzyme that destroys
  antibiotics (e.g. beta lactamase).
• The bacteria changes its permeability to the
  antibiotic (e.g. tetracycline erythromycin).
• The bacteria develops an altered receptor for
  the antibiotic (eg penicillin binding protein).

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Antibiotic Resistance in O.M.

• penicillin binding proteins

Pneumococcus
Penicillins
Cephalosporins
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Antibiotic Resistance in O.M.

• Bacteria in otitis media
• Haemophilus influenza 30-40 resistant
• Moraxella Cat. 90 resistant
• Strep Pneumonia 20-40 resistant to
  penicillins/cephalosporins

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Antibiotic Resistance in O.M.

• Recommendations of Working Group
• Amoxicillin still the first choice!
• Pneumcoccus still 1 organism
• Most pneumcocci are low to intermediately
  resistant
• We have lots of experience with this drug

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Antibiotic Resistance in O.M.

• Clinical failure after 3 days
• Consider resistant pneumococci/ H. influenza
• Amoxicillin/clavulanate 80-90 mg/kg/day
• Cefuroxime axetil 30 mg/kg/day
• IM ceftriaxone 50 mg/kg/day for 3 days

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Antibiotic Resistance in O.M.

• Recommendations of Working Group
• Failure after 10-28 days
• Same as 3 days
• Patients who fail Amoxicillin more likely to have
  TMP/SMP and Macrolide resistance.
• Expect some surprises!
• Pediatr Infect Dis J. 181-9. 1999

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Antibiotic Resistance in O.M.

• Why isnt there a magic bullet?
• 100 patients with OM 33 viral
• 66 bacterial
• 33 spontaneous cure 33 persist
• 20 eventual cure 13 remain Sx

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Antibiotic Resistance in O.M.

• What to do - Lopes rules of the Road
• AOM has a high spontaneous cure rate. because
  the immune system and host factors (like ET
  function) account for the vast majority of
  clinical cures.
• Certain individuals have a greater risk than
  others for recurrent AOM.
• Antibiotics can relieve symptoms faster, but at a
  price.

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Antibiotic Resistance in O.M.

• Treatment must be individualized according to
  risk factors such as age, daycare attendance, and
  prior history.
• Curbing antibiotic use starts with you
• see your patients often.
• avoid havingstrangers diagnose your patient.
• be communicative as to the risks and benefits
  with your parents.

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Antibiotic Resistance in O.M.

• Case 1 A 9 month old infant has a chief
  complaint of fever and fussiness since last PM.
  She has had a URI for the last several days, but
  has otherwise been well. PMH is significant for
  OM at age 6 months and day care attendance. After
  examination, you diagnosis AOM and prescribe
  Amoxicillin. After 3 days, the patient returns
  with persistent fever to 101 and fussiness. On
  exam you note that the TM is still erythematous
  and bulging. What do you do next??

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Antibiotic Resistance in O.M.

• Case 2 A 24 month old child comes into your
  office for a routine health maintenance visit. He
  has been well and has had no significant PMH. On
  examination you note a right TM is dull and has
  decreased mobility. The child has not had any
  significant symptoms. What would you do next??

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Antibiotic Resistance in O.M.

• References
• Dowell S. Acute otitis media management and
  surveillance in an era of pneumoccal resistance
  a report from the drug-resistant Streptococcus
  pneumonia working group. Pediatric Infectious
  Disease Journal 1999181-9.
• Klein JO. The in vivo sensitivity test for
  acute otitis media. Pediatric Infectious Disease
  Journal 199817774-775.
• Lipsy BA. Fluoroquinolone toxicity profiles a
  review focusing on newer agents. Clinical
  Infectious Diseases 199928352-364.

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Antibiotic Resistance in O.M.

• References (cont)
• Dowell SF. Otitis media principles of judicious
  use of antimicrobial agents. Pediatrics
  1998101165-171.
• Leibovitz E. Bacteriological efficacy of a three
  day intramuscular ceftrixone regimen in
  nonresponsive acute otitis media. Pediatric
  Infectious Disease Journal 1998171126-1131.
• Arnold KE. Risk factors for carriage of drug
  resistant Streptococcus pneumonia among children
  in Memphis, Tennessee. J. of Pediatrics
  1996128757-764.

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Antibiotic Resistance in O.M.

• References (cont)
• Nyquist A-C. Antibiotic prescribing for children
  with colds, URI, and bronchitis by ambulatory
  physicians in the United States. JAMA
  1998279875-877.
• Heikkinen T. Short term use of amoxicillin-clavula
  nate during upper respiratory tract infection for
  prevention of otitis media. Journal of Pediatrics
  1995126313-316.
• Mangione-Smith R. The relationship between
  perceived parental expectations and pediatrician
  antimicrobial prescribing behavior. Pediatrics
  1999103711-718.

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Antibiotic Resistance in O.M.

• folder Antibiotic resistance in OM