URTI

Question 1

Acute otitis media (AOM) pathophysiology

Answer 1

Preceded by a viral URTI → dysfunction of eustachian tube and mucosal swelling of middle ear Reflux of bacteria/viruses and fluid from nasopharynx into middle ear → not cleared properly by mucociliary system
Children more susceptible due to anatomy of eustachian tube (shorter and more horizontal)

Question 2

AOM Risk factor

Answer 2

Winter season outbreaks of viral infections
Episode of acute otitis media in first 6 months of life Sibling with a history of recurrent otitis media Exposure to tobacco smoke in home
Attendance at a daycare centre
Pacifier use

Question 3

MIrcobiology AOM

Answer 3

Viruses (40-45%) 
Respiratory syncytial virus (RSV) 
Rhinovirus 
Adenovirus 
Parainfluenza virus 

Bacteria 
Streptococcus pneumoniae 
Haemophilus influenzae 
Moraxella catarrhalis 
Staphylococcus aureus 
Streptococcus pyogenes

Question 4

CLinical presentation of AOM

Answer 4

Fever , 
Natural history  --- Resolves over ~ 1 week
Tugging at Ear   
Acute onset
Runny nose, nasal congestion, cough
earpain (otalgia)
Difficulty sleeping

Question 5

Diagnosis of AOM

Diagnostic criteria

Answer 5

Children who present with moderate to severe bulging of tympanic membrane (TM), or new onset otorrhea not due to acute otitis externa
OR
Children who present with mild bulging of TM and recent (< 48hrs) onset of ear pain (holding, tugging, rubbing of the ear in a nonverbal child) or intense erythema of TM)

Physical examination
- Otoscope
Discolored or reddened tympanic membrane Thickened tympanic membrane
Bulging tympanic membrane

Culture of middle ear fluid (natural or drain)

Question 6

Diagnosis of AOM
No gold standard for diagnosis
Signs and symptoms very non-specific
Young children cannot verbalize symptoms

Answer 6

Diagnosis of AOM
No gold standard for diagnosis
Signs and symptoms very non-specific
Young children cannot verbalize symptoms

Question 7

Types of Treatment for AOM

Answer 7

Non-antibiotic/Supportive treatment
Paracetamol or NSAID’s for pain and fever
Decongestants and antihistamines not shown to affect outcome
Topical analgesics not recommended

Surgical insertion of tympanostomy tubes (Ttubes)

• Allows drainage of middle ear fluid
• Only for children with recurrent episodes
  - 3 episodes in 6 months, or
  - 4 episodes in 1 year, with 1 episode in the preceding 6 month
• Observation Period (Delayed Treatment)
• Wait and See Prescription (WASP)
• Immediate Treatment

Question 8

AOM controversy

Use of antibiotic ear drops not recommended

• Local adverse effects
• Contribute to development of resistance

~ 80% of cases will resolve within 3 -4 days without antibiotics
Over-prescribing of antibiotics may contribute to development of resistance and risk of adverse effects Immediate antibiotic treatment results in ~ 1 day faster resolution of illness

Answer 8

AOM controversy

Use of antibiotic ear drops not recommended

• Local adverse effects
• Contribute to development of resistance

~ 80% of cases will resolve within 3 -4 days without antibiotics
Over-prescribing of antibiotics may contribute to development of resistance and risk of adverse effects Immediate antibiotic treatment results in ~ 1 day faster resolution of illness

Question 9

Observation Period (Delayed Treatment) AOM

Answer 9

No antibiotics
Symptomatic treatment for initial period of 48- 72 hours
If child improves → do not give antibiotics
If no improvement, or worsening → start antibiotics Must ensure appropriate follow-up and have reliable parents
Disadvantage –may need a second physician visit

Question 10

Wait and See Prescription (WASP) AOM

Answer 10

Initial physician visit → give parents prescription for antibiotic
But, fill prescription only if no improvement in 48 hours
Reduces antibiotic use (~ ⅔ of prescriptions not filled) Parents satisfied with this approach
More convenient than second physician visit

Question 11

Immediate Treatment AOM

Answer 11

Immediate Treatment
At the time of diagnosis → start antibiotic
More convenient
Expected by parents?

Question 12

types of AOM

Answer 12

Otorrhea with AOM
Unilateral or Bilateral AOM with Severe Symptoms
Bilateral AOM without Otorrhea
Unilateral AOM without Otorrhea

Question 13

Tx principle for types of AOM

Answer 13

Otorrhea with AOM
Unilateral or Bilateral AOM with Severe Symptoms
- ABX therapy

Bilateral AOM without Otorrhea

• 6 months to 2 years = ABX therapy
• > = 2years = Antibiotic therapy, OR Observation period

Unilateral AOM without Otorrhea
= Antibiotic therapy, OR Observation period

Question 14

Definition of severe and non severe illness in AOM

Answer 14

Severe illness

• Moderate to severe otalgia OR
• otalgia for ≥48 hours OR
• temperature ≥ 39°C in the past 48 hours

Non-severe illness
- Mild otalgia for < 48 hours AND temperature < 39°C

Question 15

Infants < 6 months of age
Specifically excluded from 2013 guidelines
2004 guidelines →immediate antibiotic therapy Observation period not recommended in this age group

AOM

Answer 15

Infants < 6 months of age
Specifically excluded from 2013 guidelines
2004 guidelines →immediate antibiotic therapy Observation period not recommended in this age group

AOM

Question 16

Abx for AOM first choice

Answer 16

Amoxicillin
Drug of first choice
Patient has not received amoxicillin in past 30 days,

AND
Does not have concurrent purulent conjunctivitis, AND
Not allergic to penicillin

Dose

• Children = 80-90mg/kg/day divided every 12 hours
• Adults = 500mg –1g tds

Question 17

AOM alternative first line therapy

Answer 17

Amoxicillin-clavulanate
Alternative first-line therapy

Patient has received amoxicillin in past 30 days, OR Has concurrent purulent conjunctivitis, OR

Has a history of recurrent AOM unresponsive to amoxicillin

Question 18

Abx for AOM if patient have taken ABX in previous month

Answer 18

Taken antibiotics in the previous month
High dose amoxicillin
Cefuroxime = 30mg/kg/day divided every 12 hours Bad taste may affect compliance

Second or third generation oral cephalosporins Need to cover more resistant β-lactamase producing organisms

Question 19

duration of therapy for AOM

Answer 19

Depends on age of child and severity of infection
< 2 years of age = 10 days
Severe symptoms = 10 days
2 –5 years of age with mild to moderate AOM = 7 days
≥6 years of age with mild to moderate AOM = 5 –7 days

Question 20

tx failure for AOM alternative

Answer 20

No response after 48 –72 hours → treatment failure → change antibiotics

Amoxicillin-clavulanate
Ceftriaxone IM or IV 50mg/kg daily (maximum 1g) x 3 days

Other second or third generation oral cephalosporins

Question 21

Penicillin-allergic patients AOM

Answer 21

Second or third generation oral cephalosporin, OR ceftriaxone (IM/IV)

Question 22

Severe, immediate hypersensitivity reaction in AOM what tx

less severe rxn then?

Answer 22

Azithromycin, clarithromycin
Clindamycin –only for documented Strep. pneumoniae

Less severe reaction
- Cephalosporins

Question 23

Prevention of Acute Otitis Media

Answer 23

Recommended strategies

• Eliminating exposure to tobacco smoke
• Breastfeeding for first 6 months of life
• Eliminating pacifier use in second 6 months of life

Vaccinations
- Influenza vaccine (Decreases incidence by ~30%)
- Pneumococcal vaccine
(6% reduction in incidence AND Decreases need for T-tubes, number of office visits and decreased antibiotic prescriptions)

Question 24

Sinusitis

Answer 24

Inflammation and/or infection of the paranasal sinus mucosa (and usually also involves nasal mucosa)

Question 25

CLassification of sinusitis

Answer 25

Acute –symptoms last < 4 weeks Subacute –symptoms last 4 –12 weeks Chronic –symptoms persist > 12 weeks

Question 26

pathophysiology of acute bacterial sinusitis

Answer 26

Usually preceded by a viral upper respiratory tract infection that causes mucosal inflammation Inflammation results in obstruction of sinus ostia Mucosal secretions are trapped, local defenses impaired, and bacteria trapped and can multiply and set up infection

Question 27

Risk factor for sinusitis

Answer 27

Dental infection or extraction Allergic rhinitis ``` Swimming Prior URTI Asthma Cigarette smoking Environmental pollution Mechanical ventilation Anatomic abnormalities –adenoids, deviated nasal septum, nasal polyps Nasogastric (NG) tubes ```

Question 28

microbiology

Answer 28

virus and bacterial Usually a single organism With increasing use of pneumococcal vaccine → increase in prevalence of H. influenzae and Moraxella

Question 29

Clinical presentation of acute sinusitis acute bacterial sinusitis

Answer 29

``` Acute sinusitis Nasal congestion Facial/sinus pain or pressure Nasal discharge Fever Tooth pain Reduced sense of smell (hyposmia) Malaise ``` Viral infection –usually resolves within 7 –10 days Acute bacterial rhinosinusitis Persistent signs and symptoms of acute rhinosinusitis for ≥ 10 days without evidence of clinical improvement, OR Symptoms or signs of acute rhinosinusitis worsen within 10 days after initial improvement (double worsening)

Question 30

Diagnosis for acute bacterial sinusitis

Answer 30

Primarily a clinical diagnosis Other investigations Aspiration and culture of fluid from sinuses - Gold standard - Requires skill and experience X-ray of sinuses Ultrasound of sinuses CT or MRI of sinuses - Only if suspecting complications

Question 31

Course of disease ABS

Answer 31

40-60% recover spontaneously within 7 –10 days (likely viral) If persists longer than 7 –10 days → more likely bacterial - Primary bacterial - Secondary bacterial –after a viral infection

Question 32

Tx for ABS

Answer 32

Symptomatic/adjunctive - Analgesics - Antihistamines and decongestants A) Not recommended in guidelines (vs. practice) B) No objective evidence of benefit vs. risk of adverse effects - Irrigation of nasal sinuses with saline A) Recommended as adjunctive therapy for both adults and children

Question 33

ICS for ABS

Answer 33

mometasone budesonide flunisolide fluticasone Steroids may reduce nasal and sinus mucosal inflammation and facilitate drainage of sinuses Steroid plus antibiotic more effective than antibiotic alone Some evidence of a dose-response relationship - recommended for symptomatic relief of acute bacterial rhinosinusitis (ADULT)

Question 34

Abx therapy for ABS

Answer 34

May be a small benefit with faster resolution of symptoms May prevent progression to chronic sinusitis and complications Amoxicillin alone OR amoxicillin/clavulanate Dosing Low dose = 45mg/kg/day in 2 divided doses High dose = 80 –90mg/kg/day in 2 divided doses (high dose for Areas with high prevalence of non-susceptible Strep pneumoniae isolates) Second-line antibiotics - If suspect that patient is at risk for having a resistant organism EG Recent course of antibiotics, recent hospitalization, local resistance patterns, etc., OR - Failure to improve within 72 hours with amoxicillin Amoxicillin/clavulanate Second or third generation oral cephalosporins Fluoroquinolones –levofloxacin (adults only) Doxycycline (adults only) ``` Penicillin-allergic patients - Immediate-type hypersensitivity A) Clarithromycin, azithromycin B) Cotrimoxazole C) Fluoroquinolone D) Doxycycline ``` Minor reaction A) Oral cephalosporins

Question 35

Abx therapy principle ABS

Answer 35

Watchful waiting (without antibiotic), OR Immediate antibiotic therapy Watchful waiting Start antibiotic if no improvement by 7 days, OR if condition worsens at any time Amoxicillin alone OR amoxicillin/clavulanate Recommend high dose amoxicillin over standard dose

Question 36

Duration of therpy for ABS

Answer 36

adults: 5 –10 days Lower incidence of adverse effects with shorter duration Children 10 –14 days

Question 37

Pharyngitis bacteria

Answer 37

Group A β-hemolytic Streptococcus (Streptococcus pyogenes) 80% is virus caused

Question 38

pharyngitis epidemiology

Answer 38

Children 5 –15 years of age at greatest risk Rare in adults > 30 years of age Seasonal outbreaks

Question 39

clinical presentation of pharyngitis

Answer 39

``` Sore throat Headache Abdominal pain Red, swollen uvula Pain on swallowing Enlarged, tender cervical lymph nodes Nausea and vomiting Erythema/inflammation of tonsils and pharynx (with or without patchy exudates) Runny nose Fever Cough ```

Question 40

diagnosis of pharyngitis

Answer 40

``` Difficult to distinguish viral from bacterial cause based on clinical presentation Age of patient Contact history or outbreaks in area Throat swab/culture - Gold standard for diagnosis - 24 –48 hours for results Rapid antigen detection testing - Based on immunoassay - Results within minutes - Can be done in GP office setting ``` IDSA guidelines (2012) - Rapid antigen detection test and/or culture should be done to confirm diagnosis - Cannot rely on clinical features to distinguish bacterial from viral infection

Question 41

Clinical scoring systems (Centor criteria)

Answer 41

for pharyngitis ``` 1 point each for Fever Tonsillar exudates Swollen, tender anterior cervical lymph nodes Lack of cough ``` MOH guidelines (2006) - Score < 3 → no antibiotics - Score 3 or 4 → treat with antibiotic US-based guidelines - Score 0 or 1 → no further diagnostic testing, no antibiotics - Score 2, 3 or 4 → rapid antigen test → antibiotic if positive

Question 42

complication of pharyngitis

Answer 42

Viral infection –self-limited Group A Streptococcus infection - Acute rheumatic fever (rheumatic heart disease) (Rare in developed countries) - Acute glomerulonephritis - Develop 1 –3 weeks after infection - Antibiotic treatment will prevent acute rheumatic fever, but does not prevent glomerulonephritis

Question 43

symptomatic tx for pharyngitis

Answer 43

``` Paracetamol NSAID’s Corticosteroids Lozenges Adequate fluid intake Adequate rest ```

Question 44

abx tx forpharyngitis

Answer 44

Amoxicillin or Penicillin x 10 days Other treatment options (low / standard dose) First or second generation oral cephalosporins Azithromycin/clarithromycin –penicillin allergic Clindamycin –penicillin allergic Recommend 10 day course of therapy except azithromycin ``` Amoxicillin dosing - Standard dosing = 25mg/kg bd - Once daily dosing 50mg/kg (maximum 1g) 10 days duration As effective as penicillin and divided dose amoxicillin ```

Question 45

pharyngitis Use of antibiotics shortens symptoms by ~1 – 2 days Considered significant enough to warrant treatment Prevents transmission to others and development of complications No longer contagious after 24 hours of treatment

Answer 45

pharyngitis Use of antibiotics shortens symptoms by ~1 – 2 days Considered significant enough to warrant treatment Prevents transmission to others and development of complications No longer contagious after 24 hours of treatment