Sinusitis

1
Sinusitis

• Sinusitis is an extremely common part of the
  common cold syndrome
• RVs have been detected in 50 of adult patients
  with sinusitis by RT-PCR of maxillary sinus
  brushings or nasal swabs
• Frequency of association of RV infection with
  sinusitis suggests that common cold could be
  considered a rhinosinusitis

2
Sinusitis

• Signs and symptoms
• Patient may complain of a feeling of fullness
  and pressure over the involved sinuses, nasal
  congestion, and purulent nasal discharge
• Other associated symptoms include sore throat,
  malaise, low grade fever, headache, toothache,
  and cough gt1 weeks duration
• Symptoms may last 10 14 days

3
Sinusitis

• Diagnosis
• Based on clinical signs and symptoms
• Physical examination may reveal patient described
  symptoms palpate over sinuses, observe for
  structural abnormalities such a deviated nasal
  septum
• Sinus radiographs may reveal cloudiness and air
  fluid levels
• Limited coronal CT are more sensitive to
  inflammatory changes and bone destruction

4
Sinusitis

• Management/Treatment
• 2/3 of untreated patients will improve
  symptomatically within 2 weeks
• Antibiotics may be appropriate in certain
  patients
• Supportive therapy such as humidification,
  antihistamines, analgesics, and/or
  vasoconstrictors may relieve congestion and
  fullness
• OTC decongestant sprays for use of more than 5
  days duration should be discouraged

5
Pharyngitis

• Fewer than 25 of patients with a sore throat
  have true pharyngitis
• Primarily seen in 5 18 year old population, it
  is common in adult women
• Most common cause is viral most common agent is
  rhinovirus Self-limiting usually lasts 3-4 days
• Group A, beta-hemolytic streptococcus is the
  primary bacterial pathogen in 1/3 cases
• Early detection reduces incidence of acute
  rheumatic fever and post streptococcal pharyngitis

6
Pharyngitis

• Sore throat is the prominent symptom
• Erythema
• Swelling of the affected tissues
• Exudates inflammatory cells overlaying mucous
  
• membranes
• Low-grade fever, mild general symptoms
• Difficult to differentiate from streptococcal
  infection

Caused by the same viruses that cause common cold
and Adenovirus, Enteroviruses and Influenza virus.
7
Viral Causes of Pharyngitis

• Rhinoviruses
• Adenoviruses
• Coronaviruses
• Epstein-Barr Virus
• Herpes Simplex Virus
• Parainfluenza Viruses
• Respiratory Syncytial Virus
• Influenza Viruses
• Coxsackie Viruses

8
Adenoviruses
9
Adenoviruses 51 serotypes

• Immunity correlates with the presence of type-
  specific
• neutralizing antibodies
• Endemic or epidemic, often during summer
• Incubation period 4-7 days

• Moderate to severe pharyngitis, sometimes
  exudative
• Fever and systemic symptoms
• Rhinitis and follicular conjunctivitis are
  common

10
Adenovirus 51 serotypes
Pharyngo-conjunctival fever sporadic or
epidemic association with swimming pools
Epidemic acute respiratory disease in
military recruits pneumonia in 10-20
Pneumonia in immunocompromised patients BMT
recipients mortality 60
Nosocomial transmission epidemic
keratoconjunctivitis
11
Pathogenesis

• Epithelial cells are the primary target.
• E1B and E4 proteins inhibit transport of host
  mRNA from the nucleus to the cytoplasm causing
  cell death
• The penton protein has been shown to be directly
  toxic to cells and it has been found in the blood
  of several fatal cases of adenoviurs pneumonia.

12

• Entry by the mouth, the nasopharynx or via the
  conjunctiva.
• The lower stereotypes (1,2,5 and 6) are
  ubiquitous particularly in young children
• Endemic spread takes place by the fecal oral
  route to new pools of susceptible infants and
  children.

13

• May be transmitted in swimming pools, via medical
  equipment (tonometer), and via respiratory
  droplets.
• Site of initial replication is commonly the
  oropharynx and spread is mostly local.
• Virermic spread is rare.
• Latency has been shown to be common among humans
  (in tonsils and adenoids)

14
Adenovirus Clinical Syndromes

• They infect the respiratory tract as well as the
  eye, gastrointestinal tract, urinary bladder, and
  the liver.
• On occasions, these viruses may cause disease in
  other organs such as CNS and the pancreas.
• Most human disease is associated with only
  one-third of the serotypes.
• Many adenovirus infections are subclinical

15
Respiratory Disease

• Endemic Adenovirus Respiratory Infections of
  young children
• - Represent 5 of the acute respiratory
  disease
• in children(lt5y) most commonly as
  pharyngitis or
• pharyngoconjunctival fever
• - Most common serotypes are 1,2,5 and 6 and
• occasionally 3, 4 and 7.
• - Responsible for 10 of the pneumonias of
• childhood.
• - Most patients recover but epidemics of
• adenovirus 7 have resulted in considerable
  
• mortality.

16
Acute Respiratory Disease

• Primarily affects military recruits (types 4, 7
  and occasionally 3).
• Frequently occurs under conditions of fatigue and
  crowding.
• Characterized by fever, pharyngitis, cervical
  adenitis, cough, hoarseness and rhinitis.
• Some cases have had a fatal outcome (pneumonia).

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• Pertussis like syndrome
• - It is associated with adenovirus type 5.
• Infections of the Eye
• - Acute follicular conjunctivitis
• types 3 and 7 but other types
• (1,2,4,6,9,10,15,17,20,22) have been
• incriminated.

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• Epidemic Keratoconjunctivitis
• - Types 8, 11, 19 and 37.
• - Followed by corneal subepithelial
  infiltration which may persist for a long period
  but it
• resolves completely with return of visual
  acuity
• to normal.
• - Outbreaks can be traced to eye clinics
• where an instrument (Tonometer) or a solution
  
• acts as a vehicle.

19
Viral Causes of Pharyngitis

• Rhinoviruses
• Adenoviruses
• Coronaviruses
• Epstein-Barr Virus
• Herpes Simplex Virus
• Parainfluenza Viruses
• Respiratory Syncytial Virus
• Influenza Viruses
• Coxsackie Viruses

20
Viral Infections of the Lower Respiratory Tract
21
Laryngotracheo Bronchitis (Croup)

• - An acute viral inflammation of larynx,
  trachea, and bronchi that is common in young
  children.
• - It is often preceded by a "cold".
• - Accompanied by pyrexia, hoarseness, croaking
  cough, stridor, restlessness (respiratory
  insufficiency).
• - Can be fatal - i.e. life-threatening disease.

22
Acute Bronchitis

• Inflammation of bronchi, accompanied by fever,
  cough, wheezing and "noisy chest".
• Respiratory virus infection associated with cough
• Influenza virus 7593 of cases
• Adenovirus 4590
• RVs 3260
• Coronaviruses 1050
• 40 of nonasthmatic patients with acute
  bronchitis had FEV1 ?80 of predicted
• Bronchial reactivity remained increased up to 5
  weeks after an episode of acute bronchitis

23
Acute Bronchiolitis

• Inflammation of terminal bronchioles in young
  children.
• - Bronchiole diameter is larger during
  inspiration than during expiration and this leads
  to hyperinflation of air sacs distal to
  bronchiole.
• - Complete plugging of bronchiole with air
  resorption leads to collapse. These features can
  be seen on x-ray.
• - These changes cause respiratory embarrassment
  and can be life-threatening.
• - Clinically, there is fever, rapid respiration,
  exhausting cough and wheezing.

24
Pneumonia Bronchopneumonia

• - Acute respiratory disease accompanied by
  fever, restlessness and cyanosis.
• Often not much clinical "consolidation".
• Again, can be life-threatening.

25
Causative Agents

• Paramyxoviruses
• - Parainfluenza viruses
• - Respiratory Syncytial Virus (RSV)
• - Measles virus
• Influenza
• Coronaviruses
• Adenoviruses
• Enteroviruses
• Rhinoviruses

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Parainfluenza Viruses
27
Pathogenesis and Pathology

• Initially, the mucous membranes of the nose and
  throat are involved.
• Obstruction of the paranasal sinuses and
  eustachian tubes may also occur.
• Many patients with mild disease may have limited
  involvement of the bronchi as well.
• In more extensive infections there is a tendency
  for HPIV-1 and 2 to involve the larynx and upper
  tarchea, resulting in croup.

28

• Such infections may extend also to the lower
  trachea and bronchi, with accumulation of
  inspissated mucous and resultant atelectasis and
  pneumonia.
• When HPIV-3 produces severe disease, infection of
  the small air passage is likely with the
  development of bronchopneumonia, bronchiolitis,
  or bronchitis.
• Lower respiratory tract involvement also occurs
  commonly during primary HPIV-1 and 2 infection
  about 25 of primary infections produce
  bronchitis or pneumonia.

29

• The mechanisms responsible for localization and
  severity of human parainfluenza viruses' disease
  are not known.
• Severe respiratory tract disease caused by HPIV1,
  2, and 3 generally occurs in the first 3-5 years
  of life.
• Primary infections and reinfections occur and
  most persons have had primary infections before
  the age of 5 years.

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Clinical Features

• Most infections are asymptomatic, especially in
  older children and adults.
• The incubation period is 2-6 days.
• Fever and a spectrum of respiratory infections
  are caused by HPIVs rhinorrhea/rhinitis,
  pharyngitis, croup, bronchiolitis and pneumonia.

31

• In children, the most common type of illness
  consists of rhinitis, pharyngitis, and
  bronchitis, usually with fever.
• Severe acute laryngotracheobronchitis (Croup) is
  noted in only 2-3 of primary HP1V1 or 2
  infections.
• When croup develops, the initial symptoms of
  rhinitis, pharyngitis, fever, and cough progress.

32

• After several days, subglottic region becomes
  narrower, the cough worsens and becomes brassy,
  seallike, or barking, with hoarseness and
  stridor.
• At this stage, most children recover uneventfully
  after 24-48 hours.
• In some children, however, air hunger develops,
  with cyanosis, sternal and intercostal
  retraction, and progressive airway obstruction.

33

• HP1V3 is an important cause of bronchiolitis in
  young infants and children below 2 years of age.
• When bronchiolitis or pneumonia develops, fever
  persists and the cough progresses and becomes
  somewhat productive.
• It is accompanied by wheezing, tachypnea,
  retraction, and in severe cases cyanosis.

34

• A combined bronchopneumonia-croup syndrome occurs
  in some patients.
• Rarely, parainfluenza viruses are associated with
  otitis media, parotitis, and aseptic meningitis.
• Prolonged (persistent) and particularly severe
  infections are known to occur in the
  immunocompromised

35
Respiratory Syncitial Virus
36

• RSV is the most important cause of viral lower
  respiratory tract disease in infants and children
  worldwide.
• RSV is also an important agent of disease in
  immunosuppressed adults and the elderly.
• RSV grows poorly in tissue culture and most
  experimental animals, does not shut off host
  macromolecular synthesis, and it is unstable.
• Consequently, research on RSV was impeded.

37

• RSV survives on surfaces for up to 6 hours and on
  gloves for less than 2 hours.
• The virus loses activity with freeze-thaw cycles,
  in acidic conditions and with treatment by
  disinfectants.
• Classified into two types, RSV-A and RSV-B, on
  the basis of variation in the G glycoprotein
• RSV utilizes ICAM-1 as its receptor.

38
Pathogenesis

• RSV is transmitted via large droplets, through
  fomites and via hands
• The mechanism of virus spread from upper to lower
  respiratory tract is assumed to be via the
  respiratory epithelium or through aspirated
  secretions.
• The virus is capable of cell-to-cell spread
  without emergence into the extracellular fluid.
• Viremia has not been described during infection
  of normal infants and children

39
Pathogenesis

• RSV causes the release of
• Interleukins
• Leukotrienes
• Chemokines
• This results in inflammation and tissue damage
• Presence of eosinophils and eosinophilic cationic
  protein in blood is associated with recurrent
  wheezing episodes post RSV infection

40
Pathogenesis

• Bronchiolitis
• Virus induced necrosis of bronchiolar epithelium
• Hypersecretion of mucous
• Round cell infiltration and edema of the
  surrounding submucosa
• This leads to
• Formation of mucous plugs
• Hyperinflation/collapse of distal airways
• Can also result in interstitial pneumonia
• Infants are particulary at risk due to small size
  of normal bronchioles

41
Pathology

• Lower respiratory tract involvement (signs)
  usually appear 1-3 days after the onset of
  illness (rhinorrhea)
• Inflammatory infiltration, edema, and excessive
  mucous production cause obstruction of small
  bronchioles, with either collapse or emphysema of
  distal portions of the airway.
• In those instances in which pneumonia occurs, the
  interalveolar walls thicken as a result of
  mononuclear cell infiltration, and the alveolar
  spaces may fill with fluid.

42

• There is usually a patchy appearance of these
  pathologic changes, even though disease may be
  widespread.
• Severe infections are observed in
• - Preterm infants (lt35 weeks gestational age)
• - Those with chronic lung disease
• - Those with cyanotic congenital heart disease
• - Immunocompromised hosts.