7 - URTI Flashcards
At what age does acute otitis media most often occur?
- Peak incidence at 6-24 months
- 50% by 1 year
- 70% by 3 years
- Reduces by 7 years
Signs and symptoms of acute otitis media?
- Middle ear inflammation, fluid collection (effusion)
- Rapid onset
- Otalgia (pain), otorrhea (drainage), fever, irritability, GI (vomiting, diarrhea), imbalance, hearing loss
Most common pathogens of acute otitis media?
- Viral (RSV, influenza, rhinovirus) - immunization reduces episodes by 30-40%
- S. pneumoniae
- H. influenzae
- Moraxella catarrhalis
What is otitis media w/ effusion?
- Chronic middle ear inflammation w/ fluid collection, but no acute signs of infection
- 90% spontaneous resolution w/in 3 months
Risk factors for acute otitis media?
- Bottle fed
- Daycare
- Allergies
- Passive smokes
- Craniofacial anomaly
- Immunocompromised
How is acute otitis media diagnosed?
- Clinical presentation
- Otoscopy shows impaired mobility, bulging, reddened membrane
- Tympanocentesis for severe infection, tx failure, recurrence, and immunocompromised
When should antimicrobials be used for acute otitis media?
Greatest benefit in under 2 y/o, bilateral infection, otorrhea, or immunocompromised
What is watchful waiting?
- Analgesia
- Antimicrobial rx w/ detailed instructions to initiate therapy if persistent or worsening at 48-72 h from onset of illness
- Follow-up
When should watchful waiting be considered?
6-23 months w/ mild infections and 2 years and older w/ mild-moderate infection (w/o recurrence, bilateral infection, otorrhea, sx > 72 h, craniofacial anomalies, or co-morbidities)
What are the antimicrobial options for acute otitis media?
- High dose amoxicillin 80-90 mg/kg/day given q12h (max 3g/day)
- Standard dose 40 mg/kg/day given q8h may be considered if over 2 y/o w/o risk factors for penicillin-resistance strep pneumoniae
- Alternatives = cefprozil/ cefuroxime 30 mg/kg/day given q12h; clarithro 15 mg/kg/day given q12h
What are the antimicrobial options for acute otitis media (severe infection or risk factors for resistance)? What are the risk factors for resistance?
- Beta lactam w/in 1 month, tx failure, recurrence w/in 1 month, or conjunctivitis indicative of H. influenzae)
- Amox-clav 200/28.5 or 400/57
- [Ceftriaxone 50 mg/kg IV/IM q24h x 3 days]
What is the typical response to antimicrobial therapy for acute otitis media?
Clinical improvement w/in 24-48 h and resolution w/in 72 h
What is the duration of antimicrobial therapy for acute otitis media?
- Amox or amox-clav = 5-7 days or 10 days for under 2 y/o or complicated infection
- Azithromycin = 5 days
- Others = 7-10 days
What are some possible reasons for tx failure in acute otitis media?
- Poor adherence
- Low antimicrobial dose
- Antimicrobial resistance
- Immunosuppressed
What is some essential pt counselling info for acute otitis media?
- Analgesia; avoid topical analgesics
- Avoid decongestants and antihistamines
- Adhere to antimicrobial regimen
- Potential adverse effects
What is considered recurrent acute otitis media?
> 3 episodes w/in 6 months or > 4 episodes w/in 12 months
What are some preventative measures for recurrent acute otitis media?
- Minimize risk factors, investigate associations w/ allergic rhinitis or food allergies
- Vaccination for influenzae and strep pneumo
- Continuous antimicrobial prophylaxis reduces by 1.5 episodes/year by increases risk of resistance
- Tympanostomy tubes reduces episodes by 2-3/year
What is the role of topical antimicrobials in treating acute otitis media?
- Used for children w/ tympanostomy tubes
- Would use antibiotic eye drops b/c the tube directly enters the inner ear through the ear drum
- Would use quinolones (must use sterile drops, so commonly use eye drops)
What are the signs and symptoms of acute bacterial rhinosinusitis (ABRS)?
- Nasal obstruction or purulence discharge plus pain, pressure (fullness) or lack of smell for > 7-10 days w/o improvement
- Severe sx for > 3 days w/ purulence and fever > 39 C
- Biphasic febrile-illness after 5-7 days w/ initial improvement then worsening
Most common pathogens in ABRS?
- S. pneumoniae
- H. influenzae
- M. catarrhalis
Risk factors for ABRS?
- Anatomical anomalies (septal deviation)
- Smoking, allergic rhinitis, asthma, cystic fibrosis, immunocompromised
What is the role of intranasal corticosteroids for ABRS?
- Fluticasone furoate 10 mg 2 puffs q12h or mometasone furoate 50 ug 2 puffs q12h x 14 days used for mild-moderate infection > 5-7 days
- Moderate benefit to alleviate sx and hasten recovery
- 70-90% spontaneous resolution
When are antimicrobials used for ABRS? What are the options?
- Moderate-severe infection
- Amox 500-1000 mg q8h
- Alternatives = cefprozil/ cefuroxime 500 mg q12h
- [Clarithro/ azithro] - increasing resistance
- [TMP-SMX] - increasing resistance and more adverse effects
What is the typical response to antimicrobial therapy for ABRS?
- Clinical improvement w/in 2-3 days
- Significant by 7-10 days
- Full resolution by 3-4 weeks
What is the duration of therapy for ABRS?
- 5-10 days for adults
- 10-14 days for children
What are some self-tx measures that can reduce sx of ABRS?
- Analgesia
- Normal saline nasal drops or irrigation, steam inhalation
- Decongestants and antihistamines not recommended
What are the most common pathogens and what is the epidemiology of acute pharyngitis?
- Viral (influenza, rhinovirus, coronavirus, EBV) in 90% of adults and 70% of children – resolves spontaneously w/in 5-7 days
- S. pyogenes most significant
- Peak incidence at 5-15 years
- Highly communicable for 7 days following acute illness
What is the clinical criteria used in assessing for group A strep pharyngitis?
- Exudates (red, edematous)
- Adenopathy (swollen lymph nodes)
- Fever > 38 C
- Cough absent
How is group A strep diagnosed?
- Rapid antigen diagnostic test (70-90% sensitivity, 95% specificity) throat swab, results w/in 1 h
- Confirmatory culture (90% sensitivity, 95% specificity) if negative RADT, results w/in 48 h
- Current recommendations to w/hold antimicrobial therapy until diagnostic confirmation
What are some potential complications w/ group A strep pharyngitis?
- Acute otitis media, ABRS, peri-tonsillar abscess, and necrotizing fasciitis
- Scarlet fever (< 10% of cases) w/ diffuse, popular, sandpaper-like rash that typically starts on groin or axillae and progresses rapidly to trunk and extremities
- Acute rheumatic fever (0.3-3%) w/ delayed presentation at 2-3 weeks of rash, SC nodules, arthritis
- Post-strep glomerulonephritis and strep TSS (both rare)
What are goals of antimicrobial therapy for group A strep pharyngitis?
- Limit transmission
- Hasten sx w/ 1-2 day decrease in duration
- Avoid complications
- Eradicate group A strep to prevent acute rheumatic fever
How effective are antimicrobials in treating group A strep pharyngitis?
- Clinical response rate = 70-90% and bacterial eradication in over 80%
- Higher clinical response and bactericidal eradication rates w/ cephalosporins than penicillins
What are the antimicrobial options for group A strep pharyngitis?
- Pen V 600 mg q12h (adults), 300 mg q12h (children)
- Amox (more palatable for children but more adverse effects) 500 mg q12h (adults), 40-50 mg/kg/day q8-12h (children)
- Alternatives = cefdroxil/ cephalexin; clinda; erythro
- Recurrent or chronic carrier eradication = cefdroxil/ cephalexin; clinda; pen V + rifampin
What is some essential pt counselling info for treating group A strep pharyngitis?
- Analgesics for pain control; salt-water gargle, lozenges
- Adhere to antimicrobial regimen
- Potential adverse effects
What is the typical response for antimicrobial therapy for group A strep pharyngitis?
Significant clinical improvement and bacterial eradication w/in 3-4 days
What is the duration of antimicrobial therapy for group A strep pharyngitis?
- Penicillin = 10 days
- Cephalosporins = 5 days
- Azithromycin = 3-5 days
