2. INTRODUCTION
The respiratory systems essentially comprises of three
different structural and functional units:
Respiratory tract
Lung parenchyma
Respiratory regulatory system
In addition, the pleura, the thoracic cage and the
mediastinum, are considered as important constituents of
the respiratory system
3. RESPIRATORY TRACT: function air conduction, filtering, warming and humidifying the
inspired air
Classified:
upper respiratory tract -include the nose, the mouth, the pharynx and the larynx up to the
level of the vocal cords.
lower respiratory tract- Starting with the trachea at the opening of the vocal cords up to
terminal bronchi
Airway can also be classified as:
Extra thoracic airway
Intra-thoracic extra-pulmonary airway
Intra-thoracic intra-pulmonary
4. Common Cold
The Common Cold is a viral illness in which the symptoms of rhinorrhea and nasal
obstruction are prominent
systemic symptoms and signs such as headache, myalgia, and fever are absent or mild.
=self-limited involvement of the sinus mucosa and is more correctly termed
rhinosinusitis
Etiology and epidemiology
Rhinoviruse--- the most common,
others: corona virus, bokovirus, RSV….
occur year-round, greatest from the early fall until the late spring
Young children have an average of 6-8 colds per year, 10-15% of children have at least 12
infections per year, decreases as age increases
Children in out-of-home daycare centers during the 1st year of life
5. PATHOGENS ASSOCIATED WITH THE COMMON COLD
ASSOCIATION PATHOGEN RELATIVE FREQUENCY*
Agents primarily associated
with colds
Rhinoviruses Frequent
Coronaviruses Occasional
Agents primarily associated
with other clinical
syndromes that also cause
common cold symptoms
Respiratory syncytial viruses Occasional
Human metapneumovirus Occasional
Influenza viruses Uncommon
Parainfluenza viruses Uncommon
Adenoviruses Uncommon
Enteroviruses Uncommon
Bocavirus Uncommon
6. Pathogenesis
spread by small-particle aerosols, large-particle aerosols, and direct contact.
Viral infection of the nasal epithelium can be associated:
with destruction of the epithelial lining, as with influenza viruses and
adenoviruses, or
there can be no apparent histologic damage, as with rhinoviruses and RSV
infection of the nasal epithelium is associated with an acute inflammatory
response
characterized by release of inflammatory cytokines and infiltration of the
mucosa by inflammatory cells
This acute inflammatory response causes the symptoms associated with the
common cold
Inflammation can obstruct the sinus ostium or Eustachian tube and predispose to
bacterial sinusitis or otitis media.
7. CF and DX
incubation period 1-3 days
Sore or scratchy throat usually resolves quickly and, by the 2nd
and 3rd day of illness
rhinitis(rinorhhea ,nasal obstruction),
Cough is associated with ∼30% of colds
fever and other constitutional symptoms---- Influenza viruses, RSV,
and adenoviruses .
The usual cold persists for about 1 wk, 10% last for 2 wk.
Examination of the nasal cavity might reveal swollen,
erythematous nasal turbinates
8. Muco-purluent rhinitis( thick, opaque or discolored nasal discharge), this is not an
indication for antimicrobial treatment unless it persists without signs of
improvement for more than 10-14 days suggesting possible sinusitis.
Exclude other conditions that are potentially more serious or treatable
Routine laboratory studies are not helpful for the diagnosis and management of
the common cold.
9. Management
primarily of symptomatic treatment
Either topical or oral adrenergic agents ---such as xylometazoline, oxymetazoline, or
phenylephrine
Saline nose drops (wash, irrigation)
first-generation antihistamines reduce rhinorrhea by 25-30%.
Acetaminophen not asprin
Complications
otitis media- most common complication of a cold—5 to 30%
Sinusitis 5 to 13%
Exacerbation of asthma
increasing antibiotic resistance--- due to inappropriate abc intake
10. 10
Sinusitis
Sinusitis is infectious or noninfectious inflammation of 1 or more
sinuses
occur at any age.
Third most common diagnosis for which antibiotics are prescribed
Affects 30-35 million persons/year
25 million office visits/year
Direct annual cost $2.4 billion and increasing
Added surgical costs: $1 billion
Cardiomyopathy- at any age
11. 11
Development of Sinuses
4 paranasal sinuses, each lined with pseudostratified ciliated columnar epithelium
and goblet cells
Frontal
Maxillary
Ethmoid
Sphenoid
Maxillary and ethmoid sinuses present at birth
The maxillary sinuses are not pneumatized until 4 yr of age
Frontal sinus developed by age 5 or 6
Sphenoid sinus last to develop, 8-10
The ostia draining the sinuses are narrow (1-3 mm) and drain into the ostiomeatal
complex in the middle meatus
12. 12
Physiologic Importance of Sinuses
Provide mucus to upper airways
Lubrication
Vehicle for trapping viruses, bacteria, foreign material for removal
Give characteristics to voice
Lessen skull weight
Involved with olfaction
13. The paranasal sinuses are normally sterile, maintained by the mucociliary
clearance system
2 types of acute sinusitis: viral and bacterial
Viral Rhino-sinusitis
Short lived, last less than 10 days
Sinus mucosa as well as nasal mucosa is involved
Most will clear without antibiotics
Treatment: decongestants, nasal lavage, rest, fluids
14. 14
Classification of Bacterial Sinusitis
Acute bacterial sinusitis- infection lasting 4 weeks, symptoms resolve completely
(children 30 days)
Subacute bacterial sinusitis- infection lasting between 4 to 12 weeks, yet resolves
completely
Chronic sinusitis- symptoms lasting more than 12 weeks
Recurrent Acute Bacterial Sinusitis- Episodes lasting fewer than 4 weeks and
separated by intervals of at least 10 days during which the patient is totally
asymptomatic
Or 3 episodes in 6 months or 4/year
15. 15
Bacteria Involved in Acute Bacterial Sinusitis
Streptococcus pneumoniae 30%
Haemophilus influenza 20%
Moraxella catarrhalis 20%
Staphylococcus aureus, other streptococci, and anaerobes
are uncommon causes
16. 16
Bacteria Involved in Chronic Sinusitis
Anaerobes includes
Fusobacterium nucleatum,
Prevotella spp,
Porphyromonas spp, and
Peptostreptococcus spp
Aerobes
Aerobic gram-negative bacilli, such as Pseudomonas aeruginosa, Klebsiella pneumoniae,
Proteus mirabilis, Enterobacter spp, and Escherichia coli
Staphylococcus aureus
Staphylococcus epidermidis
20. 20
Sinus Transillumination
Helpful in older children and adults
Normal transillumination decreases chance of fluid in the sinus
No light reflex suggests mucopurulent material or thickening of
nasal mucosa
cannot reveal the etiology, whether it is viral or bacterial in
origin.
In children, transillumination is difficult to perform and is
unreliable
Inexpensive screening tool
22. Diagnosis
based on history
Persistent symptoms of upper respiratory tract infection, including nasal
discharge and cough, for >10-14 days without improvement, or
severe respiratory symptoms, including fever of at least 102?F (39?C) and
purulent nasal discharge for 3-4 consecutive days, suggest a complicating
acute bacterial sinusitis
Sinus aspirate culture----the only accurate method of diagnosis
Bacteria are recovered from maxillary sinus aspirates in 70%
sinus plain films, CT scans
Including opacification, mucosal thickening, or presence of an air-fluid
confirm the presence of sinus inflammation but cannot be used to
differentiate the etiology
24. 24
Treatment of Acute Bacterial Sinusitis
50-60% of children with acute bacterial sinusitis recover without antimicrobial
therapy
antimicrobial treatment to promote resolution of symptoms and prevent
suppurative complications
Amoxicillin for 10-14 days or for 7 days after resolution of symptoms
First line choice in most areas
because of its efficacy, low cost, side-effect profile, and narrow spectrum
for the penicillin-allergic include trimethoprim-sulfamethoxazole, cefuroxime
axetil, cefpodoxime and macrolides
Where beta-lactanase resistance is an issue
High dose Amoxicillin/clavulanate or azithromycin
Frontal sinusitis can initiation of parenteral ceftriaxone
25. 25
Complications of Sinusitis
Orbital---most often secondary to ethmoiditis
periorbital cellulitis and
orbital cellulitis
Brain
epidural abscess, meningitis, cavernous sinus thrombosis, subdural
empyema, and brain abscess
Bone
osteomyelitis
26. Pharyngitis
Definition: Inflammatory Syndrome of the pharynx caused by several microorganisms
Causes:
Viral– most common
adenoviruses, coronaviruses, enteroviruses, rhinoviruses, RSV, EBV,HSV,
metapneumovirus
Bacteria- The most bacterial cause is Group A Streptococcus (Streptococcus pyogenes)
15 to 30%
GABHS--- uncommon before 2 to 3 yr
peak incidence in the early school years, and declines in late adolescence and
adulthood
OTHERS-GCS, Mycoplasma, Arcanobacterium, Francisella, Neiseria, Corynbacteria
27. Clinical feature
GAS- The incubation period is 2-5 days
rapid onset sore throat, fever, headache, GI symptoms
cough is absent
pharynx is red, and petechiae may be there
tonsil enlarged and covered yellow blood tingled exudate
uvula may become red, stippled and swollen
anterior cervical L.node enlarged and tender
The illnesses attributed to group C streptococcus and A. haemolyticum are generally
similar to those caused by GABHS
Viral-gradual onset with rhinorrhea, cough and diarrhea
conjunctivitis, coryza, hoarseness, and cough
other symptoms according to the cause
Measles> cccp
cough
coryza
conjunctivitis
photophobia
28.
29. Diagnosis
identification of GABHS
Rapid antigen test—high specificity ≥95 percent and a sensitivity that
varies between 70 and 90 percent
if +ve----- no need culture
Throat culture---- gold standard
false –ve----- enadequate swab and ABC use
false +ve------ in asymptomatic carrier 5 to 21 percent of
children b/n 3 and 15 years of age
GAS molecular tests--- both sensitivity and specificity are reported to be
≥98%
--- more expensive than throat culture
Most children and adolescents with negative microbiologic tests for GAS have
viral pharyngitis, which is a self-limited condition and can be treated
symptomatically
30. McIsaac scoring
one point for each of the following:
1. Age 3 to 14 years
2. tonsillar swelling or exudates
3. Tender, enlarged (>1 cm) anterior cervical lymph nodes
4. Temperature >38°C (100.4°F)
5. Absence of cough
overestimates the likelihood of GAS
31. Treatement
indication for abc are culture +ve and Ag positive for GABS, Dx of scarlet fever, Hx of RF,
contact with proven GBS pharyngitis, hx of recent RF in family member
Antibiotics- pencillin
amoxicillin for 10 days or
benz.penicillin
-Erythromycin
- the primary goal of abc is to prevent rheumatic fever and is completely successful
if given within 9 days
For eradication of carrier clindamycin for 10d
- other supportive measures
anti pyretic like paracetamol
gurgling with warm salt water and local anasthetic spray
TONSILOCTOMY ------ for severe and recurrent GABHS tonsilits
→> seven in previous year and > 5 in preceding 2 years
32.
33. Recurrent Pharyngitis
Definition:
≥7 episodes in the previous year or ≥5 in each of the preceding 2 yr, or ≥3 in
each of the previous 3 yr
Causes:
reinfection with the same M type if type-specific antibody has not developed;
poor compliance with oral antibiotic therapy;
macrolide resistance if a macrolide was used for treatment; and
infection with a new M type
Management
Treatment with intramuscular benzathine penicillin eliminates
nonadherence to therapy
Tonsillectomy may lower the incidence of pharyngitis for 1-2 yr among
children
35. OTITIS MEDIA
The term otitis media has 2 main categories:
I. acute infection, which is termed suppurative or acute otitis media (AOM); and
II. inflammation accompanied by effusion, termed nonsuppurative or secretory OM, or otitis
media with effusion (OME)
Middle-ear effusion (MEE) is a feature both of AOM and of OME and is an expression
of the underlying middle-ear mucosal inflammation
These 2 main types of OM are interrelated: acute infection usually is succeeded by
residual inflammation and effusion
bacteria- isolated in 65 – 75 % of ME exudates
-Streptococcus pneumoniae(40%),
-Hemophilus influenzae(25-30%), and
-Moraxella catarrhalis(10-15%)
o Virus –mostly together with bacteria
- RSV and rhinovirus
36. Epidemology
Over 80% of children will have experienced at least one episode of otitis
media (OM) by the age of 3 yr.
The peak incidence and prevalence of OM is during the 1st 2 yr of life.
OM is the leading reason for physician visits and for use of antibiotics
OM is the most common reason for prescribing antimicrobial drugs to children
Age
the development of at least 1 episode of OM has been reported as 63-85% by
12 mo and 66-99% by 24 mo of age
less well-developed immunologic defenses and less favorable eustachian
tubal factors
37. Gender
Greater in boys than in girls and greater severity in boys
Socioeconomic Status
Poverty has long been considered an important contributing factor to both
the development and the severity of OM.
Elements contributing to this relationship include crowding, limited
hygienic facilities, suboptimal nutritional status
Breast Milk Compared to Formula Feeding
In general, studies have found a protective effect of breast milk feeding
against OM
Exposure to Tobacco Smoke
Exposure to Other Children
38. Congenital Anomalies
OM is universal among infants with unrepaired palatal clefts, and is also
highly prevalent among children with submucous cleft palate, other
craniofacial anomalies, and Down syndrome.
The common feature in these congenital anomalies is a deficiency in the
functioning of the Eustachian tubes, which predisposes these children to
middle ear disease
Vaccination Status
39. Etiology
nontypeable H. influenzae ---- 40 to 50%
S. pneumoniae ---30-50% of cases
M. catarrhalis representing the majority of the remaining cases.
Other pathogens include group A streptococcus, Staphylococcus aureus, and
gram-negative organism
respiratory viruses also may be found in middle-ear exudates of children with
AOM, either alone or, more commonly, in association with pathogenic
bacteria.
Of these viruses, rhinovirus and respiratory syncytial virus (RSV) are found
most often
40. PATHOGENESIS
Otitis Media usually follows an URI in which there is edema of the Eustachian
tube, leading to blockage.
Stasis of these middle ear secretions lead to infection and irritation
Viral infection of the URTI results in release of cytokines and inflammatory
mediators, some of which may cause Eustachian tube dysfunction.
Respiratory viruses also may enhance nasopharyngeal bacterial colonization
and adherence and impair host immune defences against bacterial infection
Other factors: allergic rhinitis, nasal polyps, adenoidal hypertrophy
The maturation of this immune system during early childhood is most likely
the primary event leading to the decrease in incidence of OM
41. Clinical Manifestations
ear pain
In young children may be manifested by irritability or a change in sleeping or
eating habits and holding or tugging at the ear
Fever
purulent otorrhea
Balance difficulties or disequilibrium
Hearing loss
Examination of the Eardrum
Otoscope- normal tympanitic mb is slightly concave, pearly gray and
transleucent
Acute otitis media:- bulged, erythema or abnormally white if effusion
and absence of motility
(atleast 2 of 3)
44. Treatment
Antibiotics -First line
amoxicillin
azithromycin
bactrim
Second line
augmentin
cefuroxime
ceftiaxone(IM)
*Duration of treatment is 10 days
Myringotomy
Tympanocentesis and tympanostomy tube insertion
45. CRITERIA FOR INITIAL ANTIBACTERIAL-AGENT TREATMENT OR OBSERVATION
Nonsevere illness is mild otalgia and fever <39?C in the past 24 hr. Severe illness is
moderate to severe otalgia or fever ≥39?C.
Observation is an appropriate option only when follow-up can be ensured and antibacterial
agents started if symptoms persist or worsen
AGE CERTAIN DIAGNOSIS UNCERTAIN DIAGNOSIS
<6 mo Antibacterial therapy Antibacterial therapy
6 mo-2 yr Antibacterial therapy
Antibacterial therapy if
severe illness;
observation option* if
nonsevere illness
≥2 yr
Antibacterial therapy if
severe illness;
observation option* if
nonsevere illness
Observation option*
