1. Upper Respiratory Tract Infections

2. Burden of Upper respiratory tract infection (URI)
Significant morbidity and direct health care costs
Direct costs of $ 17 billion annually
Excessive use of antibiotics a major issue
Occasionally leads to fatal illness

3. Common cold - Definition
The common cold is a viral infection
upper respiratory tract, nose, and throat
More than 100 viruses can cause a common cold
signs and symptoms tend to vary greatly
Preschool children are at greatest risk of frequent colds
children average 8 per year, adults 3
Most people recover from a common cold
a week or two

4. The Common Cold - Causes
Etiologies
Rhinoviruses 30 to 35%
Coronaviruses about 10%
Miscellaneous known viruses about 20%
Influenza and adenovirus-30%
Presumed undiscovered viruses up to 35%
Group A streptococci 5% to 10%
Parainfluenza was the first respiratory virus isolated (1955)
Seasonal variation
Rhinovirus early fall
Coronavirus- winter

5. Transmission of Rhinoviruses
Direct contact is the most efficient means of transmission
40% to 90% recovery from hands
Brief exposure (e.g., handshake) transmits in less than 10% of instances
Kissing does not seem to be a common mode of transmission

6. Transmission through droplet dispersion (Courtesy-American Assoc
Transmission through droplet dispersion (Courtesy-American Assoc. for the Advancement Of Science)

7. Molecular surface of a Human rhinovirus, showing protein spikes

8. Risk factors Cold viruses are almost always present in the environment
But the following factors can increase your chances of getting a cold:
Age
Immunity
Time of year

9. Clinical characteristics
Incubation period hours
Nasal obstruction, drainage, sneezing, scratchy throat
Median duration 1 week - but 25% can last 2 weeks
Pharyngeal erythema is commoner with adenovirus than with rhino or coronavirus

10. Common Cold - Symptoms Common symptoms are Sometimes accompanied by
sore throat
runny nose
nasal congestion
sneezing
Sometimes accompanied by
conjunctivitis
myalgias
fatigue
Sinusitis often present by CT scan; “rhinosinusitis” might be a better term

11. Common Cold - Complications
Acute ear infection (otitis media)
Wheezing
Sinusitis
Other secondary infections

12. The common cold

13. Diagnosis and treatment
Main challenge is to distinguish between uncomplicated cold and streptococcal pharyngitis or bacterial sinusitis
Marked exudate or pharyngeal erythema suggests
Streptococcal infection
Adenovirus
Diphtheria
Rapid antigen tests for group A streptococcus
Rapid techniques for influenza, RSV, parainfluenza
Treat with NSAIDs and whatever else your grandmother advises

14. A Rapid Strep Test kit

15. Acute sinusitis - Definition
causes the cavities around your nasal passages to become inflamed and swollen
With acute sinusitis, it may be difficult to breathe through the nose
Acute sinusitis is most often caused by the common cold

16. Acute sinusitis - Causes
Acute sinusitis can be caused by:
Viral infection Bacterial infection
Fungal infection
Some health conditions can increase the risk of getting a sinus infection include:
Allergies Nasal polyps or tumors
Deviated nasal septum Tooth infection
Other medical conditions

17. Acute bacterial sinusitis
Epidemiological studies suggest 1 billion cases of viral rhinosinusitis occur annually in the US
Of these 0.5 – 2 % are complicated by bacterial sinusitis
Acute sinusitis typically starts with viral infection that paves the path for pathogenic bacteria
The major pathogens are Streptococcus pneumoniae and Haemophilus influenzae
Nose blowing generates high intranasal pressures that deposit bacteria into the sinus cavity
More common in adults than in children

18. Acute bacterial sinusitis - Causes
Community acquired bacterial sinusitis
S. pneumoniae
H. influenzae
S. pyogenes
Nosocomial sinusitis
Seen in critically ill, mechanically ventilated
S. aureus
Pseudomonas aeruginosa
Serratia marcescens
Fungal

19. Bacterial sinusitis - Clinical features
Sneezing
Nasal discharge
Facial pressure
Fever
Purulent drainage
Headache
Sinus imaging not routinely recommended

20. Chronic sinusitis Chronic sinusitis
a common condition in which the cavities around nasal passages (sinuses) become inflamed and swollen
for at least eight weeks, despite treatment attempts

21. Chronic sinusitis - Causes
Bacterial
Cultures show a variety of opportunistic pathogens including anaerobes but problem is mainly anatomic, not microbiologic
Fungal
Suspect especially when a single sinus is involved

22. Numerous microorganisms can be isolated from patients with chronic sinusitis
Mixtures of aerobic and anaerobic bacteria are common
The general conclusion at this time is that in most patients, no single microorganism can be assigned a pathogenic role

23. In some patients, however, P. aeruginosa or S
In some patients, however, P. aeruginosa or S. aureus seems to be clearly pathogenic
There are data suggesting roles for H. influenzae and Moraxella catarrhalis in children
In these instances, especially in children, Streptococcus pneumoniae and Haemophilus influenzae may be important
Numerous bacteria including gram-negative rods have been isolated with patients with post-operative sinusitis

24. Acute pharyngitis Inflammatory syndrome of the pharynx
Most cases are viral
Most important bacterial cause is Streptococcus pyogenes (15-20%)
Presents with sore or scratchy throat
In severe bacterial cases there may be odynophagia, fever, headache

25. Miscellaneous causes of pharyngitis
Primary HIV infection
Gonococcal infection
Diphtheria
Yersinia entercolitica (can have fulminant course)
Mycoplasma pneumoniae
Chlamydia pneumoniae

26. A case of strep throat

28. Severe Acute Respiratory Syndrome (SARS)
Caused by a previously unrecognized coronavirus—genome has now been sequenced
Clinical manifestations are similar to those of other acute respiratory illnesses—notably, influenza
Cases in U.S. associated mainly with travel or as secondary contacts
SARS coronavirus (SARS-CoV) is causative of the syndrome

29. SARS: Radiographic findings
Early: a peripheral/pleural-based opacity (ground-glass or consolidative) may be the only abnormality. Look especially at retrocardiac area
Advanced: widespread opacification (ground-glass or consolidative) tending to affect the lower zones and often bilateral
Pleural effusions, lymphadenopathy, and cavitation are not seen.

30. Croup Rhinorrhea, sore throat, mild cough, fever
Parainfluenzae and influenza can be identified by nasopharyngeal swab
Rapid tests are available
Treat with vaporizers, nebulized adrenaline
Systemic or nebulized corticosteroids in the severely sick
The steeple sign as seen on an AP neck X-ray of a child with croup

31. Acute Epiglottitis
A life-threatening cellulitis of the epiglottis and adjacent structures
Onset usually sudden (as opposed to gradual onset of croup); drooling, dysphagia, sore throat
H. influenzae the usual pathogen both in children (the usual patients) and adults

32. Acute suppurative parotitis
Uncommon, but high morbidity and mortality
Usually associated with some combination of dehydration, old age, malnutrition, and/or postoperative state
S. aureus the usual pathogen

34. Otitis externa
Acute, localized: often S. aureus, S. epidermidis or S. pyogenes
Acute diffuse (swimmer’s ear): gram-negative rods, especially Ps. Aeruginosa ; Rx: topical quinolones
Chronic: mainly with chronic otitis media
Malignant: life-threatening infection in diabetics, elderly, immunecompromised

35. Malignant otitis externa
Diabetes mellitus
Pseudomonas aeruginosa
Osteomyelitis of the temporal bone
Involvement of vital structures at base of brain

36. Acute otitis media
S. pneumoniae and H. influenzae the leading causes in all age groups (most H. flu is from non-typable strains and not “B”)
Moraxella catarrhalis: 10% of cases
Some cases may be viral (RSV, influenza, enteroviruses)
Mycoplasma pneumoniae: inflammation of the tympanic membrane (“bullous myringitis”)

37. Acute otitis media
Critical role of eustachian tube as conduit between nasopharynx, middle ear, and mastoid air cells
Children have shorter, wider eustachian tubes than adults

38. Diagnosis and treatment
Presence of fluid in the middle ear AND
Ear pain, drainage, hearing loss
The fluid may take weeks to resolve
Amoxicillin remains the drug of choice
Beta-lactamase producing strains of H. influenza will need amoxicillin/clavulanic acid or cephalosporins

39. Otitis Media

40. Vesicular lesions
Herpangina
Uncommon
Due to coxsackieviruss
Small, 1-2 mm vesicles on the soft palate, uvula, and anterior tonsillar pillars which rupture to form small white ulcers
Occurs mainly in children
Also think of Herpes simplex virus when you see vesicular lesions

41. Dr. Carlo Urbani ( )
2/28/03: Recognized SARS while examining a patient in Hanoi.
Identified outbreak and raises the alarm.
Stayed caring patients despite multiple illnesses in staff—sent wife and three children back to Italy
3/29/03: Died of SARS