ID class

  1. Risks / Benefits of Antibiotics
    • Benefits:
    • Improve outcomes in patients with susceptible bacterial infections
    • Shorten illness
    • Prevent complications
    • Save lives

    • Risks
    • Resistance
    • Super infections
    • MRSA
    • Side effects
    • Cost
  2. URI
    Infections of the upper-airway (not including the lungs)

    Typically include rhinitis, pharyngitis, otitis, laryngitis, and bronchiti
  3. Epidemiology of URIs
    The vast majority of new antibiotic prescriptions (not refills) written in ambulatory care clinics are for URIs

    • Huge resistance risks
    • Significant healthcare costs
  4. What causes URIs
    Viruses predominate

    Virus itself does not typically cause toxicity

    Bacteria may cause host destruction
  5. Acute pharyngitis
    onset of pain in the throat manifested especially on swallowing, sometimes associated with tonsil exudates
  6. Etiology of Pharyngitis (virus)
    • Rhinovirus, coronavirus, adenovirus, influenza virus, parainfluenza virus, and Epstein-Barr virus
    • Not exudative
  7. Bacterial
    • Group A Streptococcus pyogenes (GAS) is the major cause of bacterial pharyngitis
    • Other less common bacteria include:

    Mycoplasma pneumoniae, Chlamydophila pneumoniae, Corynebacterium diphtheriae
  8. Clinical presentaion of URI

    • Mild to moderate pharyngeal discomfort
    • Soreness, scratchiness, or irritation
    • Nasal signs and symptoms
    • Cough
    • Systemic complaints rarely present
    • Low fever, no chills


    • All of the above remain possible
    • Systemic complaints more prominent
    • Fever, headache, chills, abdominal pain
    • Pharyngeal membrane is a “fiery red”
    • Patchy, grayish-yellow exudates on the tonsils
    • Tender, enlarged cervical nodes
  9. Diagnosis of URI
    • Rapid streptococcal antigen test
    • >95% specificity; 60%-90% sensitivity
    • Negative results may need to be confirmed with culture
    • Quickà can be don’t right in the drs office.
    • 1/4th of the time in can miss it if its there
    • Usually do this then if it doesn’t get better they will use a culture or order ab

    Throat culture

    • 95% sensitivity
    • Typically takes 1 to 2 days
    • Used to confirm negative results from the rapid streoptococcal antigen test
  10. Therapy of URI (viral)
    Viral cause suspected:

    • No direct therapy indicated
    • Symptomatic treatment (should initiate immediately to get symptomatic relief)
    • Warm saline gargles
    • Liquids
    • APAP or NSAIDS for pain
  11. Rheumatic Fever
  12. Inflammatory disease that may develop weeks to months after an untreated group A streptococcal infection
    • Caused by antibody cross-reactivity
    • May cause damage to heart valves, joints, skin, brain
    • Body produces specific antigens that causes cross reactivity that damages organs
  13. Antibiotic Therapy for GAS
    Penicillin is still the treatment of choice

    • Cheap, effective, safe, narrow-spectrum
    • Amoxicillin may be used (generally more palatable)

    Macrolides (generally reserved for PCN allergic patients) – RESISTANCE IS A PROBLEM

    • Erythromycin- used less--- qid and GI side effects
    • Azithromycin—used a lot---qd and lasts longer and less side effects
    • Clarithromycin
    • Group A strep is very sensitive so that’s good. Very little resistant with penicillin products
  14. Length of therapy for uri
    • Generally takes 10 days to eradicate bacteria
    • Shorter courses have been studied with success
    • Length is always a guessing game
  15. Otitis Media
    Clinical classification

    1. Acute otitis media (AOM) : The first infection

    2. Recurrent AOM : Get it and it gets better but it never really goes away

    3. OM with effusion : When children have a lot of fluid build up that’s causing pressure

    4. Chronic purulent OM : drainage issue
  16. Etiology of otitis media
    • Streptococcus pneumoniae 20%-35%
    • Haemophilus influenzae 20%-30%
    • Moraxella catarrhalis <20%

    • No bacterial pathogen found in 20%-30% of cases
    • Viral etiology found in up to 40%-45% of cases
  17. s/s of otitis media
    • Fever, tugging of the ear, pain
    • Redness and bulging of tympanic membrane
    • Runny nose

    • Rhinorrhea, cough, irritability, anorexia, headache, vomiting, diarrhea
    • Suction to take milk out of bottle hurts – stop eating
  18. diagnosis of otitis media
    • Otoscope (redness and bulging present)
    • Tympanocentesis (recovery of organism)
  19. Therapy of otitis media
    • abs
    • symptomatic therapy
  20. Acute otitis media treatmetn
    • Mild illness
    • high dose amoxicillin (80-90 mg/kg/day) divided twice daily

    Moderate-severe illness

    High dose amoxicillin- clavulanate (80-90 mg/kg/day of amoxicillin component) divided twice daily
  21. Sinusitis
  22. inflammation and/or infection of the paranasal sinus mucosa
  23. s/s of sinusitis
    Excess nasal secretions, posterior nasal drip, facial pain, and pain in the vertex of the head
  24. Bacterial etiology of sinusitis
    • Streptococcus pneumoniae and Haemophilus influenzae predominate (>70% of cases)
    • Moraxella catarrhalis third likely bacterial pathogen
    • Less likely pathogens seen:

    Staph aureus, Streptococcus pyogenes, fungi, anaerobes
  25. Therapy for sinusitis
    early, mild disease:

    • Initiate therapy for symptoms
    • Decongestants, nasal saline

    If patient has moderate to severe disease for ≥7 days

    Begin antimicrobial therapy
  26. Ab therapy for sinusitis
    Amoxicillin 500mg PO TID

    • allergies:
    • Azithromycin, clarithromycin, quinolone, doxycycline
    • 2nd generation cephalosporin? (non-type 1 allergy)
    • Cefprozil, cefuroxime

    rug resistant S. pneumoniae suspected?

    High dose amoxicillin: 1000mg PO TID

    • This is being used more and more when pneumo is resistant
    • Clindamycin
    • Respiratory fluoroquinolone (levofloxacin, moxifloxacin,)
  27. Duration of therapy for sinusitis
    7-14 days

    z-pac: 5 days
  28. Acute Bronchitis
    inflammation of the large elements of the tracheobronchial tree

    S/s: cough
  29. Types of Bronchitis
    • Acute:
    • Generally occurs as single episodes
    • Common in children and adults


    • Production of sputum on most days for at least 3 months per year for more than 2 years
    • Primarily affects adults
    • Wont occur in a healthy--- usually have other issues
  30. Etiology of bronchitis
    Acute bronchitis:

    Viruses cause most cases

    • Rhinoviruses, influenzae, parainfluenza, adenoviruses
    • Bacterial infection possible

    S. pneumoniae, H. influenzae, atypical pathogens
  31. s/s of bronchitis
    cough fever
  32. Ab therapy of bronchitis
    Directed against most common bacterial pathogens

    Streptococcus pneumoniae, H. influenzae, M. pneumoniae

    • Macrolides, doxycycline, fluoroquinolones
    • Need to treat for atypical
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