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Acute Otitis Media. Objectives. Define otitis media (OM), acute otitis media (AOM) and otitis media with effusion (OME) Be familiar with the epidemiology of AOM List causative pathogens in children with AOM and current bacteriologic resistance patterns.
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Objectives • Define otitis media (OM), acute otitis media (AOM) and otitis media with effusion (OME) • Be familiar with the epidemiology of AOM • List causative pathogens in children with AOM and current bacteriologic resistance patterns
1999 7th International Symposium on Recent Advances in Otitis Media Terms and Definitions
Distinguishing AOM from OME Hoberman A. Clinical Pediatr 2002;41:373-390 (reprinted with permission)
Prevalence of Otitis Media • 1993 - 1995 (NCHS),2 OM accounted for • 18% ambulatory visits (1-4 yr) • 14% visits during the 1st yr of life • AOM episodes diagnosed2 • 81% in pediatric practices • 13% in hospital ED • 6% in hospital outpatient departments
Prevalence of Otitis Media • Peak incidence of OM occurs during the first 2 years • 60%-70% of children have >1 AOM before 1st birthday4,5 • Early onset (<6 mo) associated with recurrent AOM and chronic OME • Recurrent AOM, >3 episodes/6 mo or >4 episodes/yr, ~ 20% of children
Prevalence of Otitis Media • AOM and OME, segments of a disease continuum7 • Mean cumulative time with MEE (AOM or OME)5 • 20.4% in 1st yr • 16.6% in 2nd yr
Risk Factors for OM • Host factors • Age/Gender • Genetic predisposition • Cleft palate/Down syndrome • Allergy/Immunity • Environmental factors • Daycare/Siblings • Bottle (versus breast) feeding • Pacifier use • Smoking • Low socioeconomic status • Season/Upper respiratory infections
Host-Related Risk Factors Age/Gender • AOM most prevalent between 6 and 11 mo • Shorter, horizontal lying eustachian tube • Males, higher cumulative time with OME
Environmental Risk Factors Day Care Attendance • Most important risk factor • 50-70% children 6-18 mo attending day care have bilaterally persistent OME • Number of children in day care, hours spent, age at entry and siblings in daycare influence risk • Day care increases risk of infection, use of antibiotics, thus increasing selection of resistant organisms
Environmental Risk Factors Exposure to Household Cigarette Smoke • Positive relationship between smokers in household and OM during 1st but not 2nd year5 • Increased levels of cotinine in saliva correlated with abnormal tympanograms and number of smokers • Association between early AOM onset and cotinine in urine not found
Pathophysiology of AOM Otitis Media Infection Host Factors Anatomic/Physiologic Dysfunction • Immature/impaired immunology • Eustachian tube dysfunction • Familial predisposition • Type of milk (breast or formula) • Cleft Palate • Gender • Race EnvironmentalFactors Allergy Bluestone CD. Pediatr Infect Dis J. 1996:15:281-291 (reprinted with permission)
Pathophysiology of AOM • Eustachian tube (ET) functions include ventilation, protection and clearance of secretions • Impairment ET function MEE • URI inflammation of nasopharynyx (NP) and ET • Inflammation ET dysfunctionnegative middle ear pressure • Organisms colonizing NP aspirated into middle ear resulting in AOM
Resistant (MICs ³2 µg/mL) Intermediate (MICs 0.12-1 µg/mL) Microbiology: Antimicrobial Resistance Year# Isolates 1988-891476 1990-911524 1992-931799 1994-9521527 1997-9821601 1999-0021531 2001-0231925 • Doern GV. Am J Med. 1995; 99:3S-7S • Doern GV. ACC. 2001;45:1721 • 3. Doern GV. Unpublished data
Bacterial Resistance Against β-Lactam Abx Peptidoglycan cell wall β-lactamase enzymes inactivate β-lactam antibiotics Plasma membrane Altered PBPs Cytoplasm Resistance increases as altered PBPs accumulate Clavulanic acid irreversibly binds to β-lactamase protecting β-lactam antibiotics from enzymatic cleavage Antibiotic β-lactamase Clavulanic acid Normal PBP Altered PBP Jacobs MR. Am J Manag Care. 1999;5(suppl 11):S651-S661.
Bacterial Resistance Against Macrolides Bacteria alter macrolide binding site(ermAM gene, MLSB phenotype) Macrolide unable to block protein synthesis Bacterial efflux pumps(mefE gene, M phenotype) Macrolide excreted from cell Ribosomes 50 50 50 30 30 30 Cytoplasm Macrolide Jacobs MR. Am J Manag Care. 1999;5(suppl 11):S651-S661
Antibiotic Options • 1st Line • Amoxicillin : low versus high dose • Augmentin • PC allergy Zithromax • 2nd Line • Cephalosporins • Zithromax
The Observation Option • Limited to healthy kids over the age of 6mos • May observe age group 6 months to 2 years if AOM is uncertain and pt has nonsevereillness. • What defines a severe illness? • fever ≥ 39 C or 102.2 F, severe otalgia • Older than 2 years if nonsevere illness • Family has access to doctor, and family member to close eye on patient
What is your diagnosis? Otitis Media with Effusion
What is your diagnosis? Eustacian Tube Dysfunction
Bonus Question -What is this? Cholesteoma