1. Bronchiolitis Bronchiolitis fa Dr. S. Alyasin Associated Professor
Pediatric Department

2. Bronchiolitis
-LRT disease common in infant resulting inflammatory obstruction of small airway
-By age of 2 years (1-3 mo.)
-Winter- early spring
-Infants with respiratory distress , tachypnea and wheez

3. Acute bronchiolitis : Etiology
Viral infection
RSV>50%
Parainfluenza – adenovirus – mycoplasma
Human meta-pneumovirus & bocavirus (primary or co-infection)
Sometime confused clinically with bacterial pneumonia but it rarely followed by bacterial
super-infection
Pertussis may be co-infection
In co-infection ; is more severe

4. Acute bronchiolitis : Epidemiology
In USA children < 1y/o are hospitalized annually (RSV) rate: -Day care center - survival of premature baby

5. Acute bronchiolitis: Epidemiology
More common in:-
- boys
– not breast fed
crowded condition
- younger mother smoked during pregnancy
Source of infection: older family member with URI
Older children tolerate bronchiolar edema

6. Acute bronchiolitis : Pathogenesis
Bronchiolar obstruction (edema- mucus- cellular debris)
Airflow is inversely proportional to th 4th power of radius
Resistance is increased in inspiration < expiration: air trapping & over inflation
If obstruction become complete: atelectasis
V/Q mismatch: hypoxemia: then hypercapnia

7. Pathophysiology Not all infected infant develops LRTI Smaller airway
Diminished lung function
Eosinophil degranulation , ECP
IgE
Chemokine IL8 , MIP1α- RANTES (regulated on activation, normal T cell expressed and secreted)
IFNδ, leukotriene

8. Acute bronchiolitis : Clinical manifestation
Exposure to URI
Sign of URI
Diminished appetite and fever (T range: subnormal or markedly elevated)
Gradually resp distress- cough – wheez-irritable –interfere with feeding
Apnea may be prominent (age < 2mo or premature)
Might fine crackles or overt wheeze
Prolong Exp
Decrease breath sound  severe disease
Liver & spleen ( hyperinflated)

9. Acute bronchiolitis Dx
Previously healthy infant with first-time wheezing in outbreak
CXRay hyperinflated with patchy atelectasis
WBC: Nl
PCR – IF – Culture (if dx is uncertain or for epidemiologic purpose)
Trial of bronchodilator reverse asthma & occasionally bronchiolitis but can worsen bronchial malacia

10. CX ray: hyper inflation, patchy atelectasis, 10% nl

11. peribronchial, and interstitial thickening.
bilateral hyperinflation (most evident on the lateral), with increased perihilar,
peribronchial, and interstitial thickening.
bilateral suprahilar ill-defined opacities

12. Acute bronchiolitis Df Dx
-Asthma – CF – congenital malformation – F.B. – GER – trauma & tremor - Cardiogenic asthma(pul. Congestion)

13. Acute bronchiolitis : Treatment
Admission:
-hypoxia
– inability to take oral feeding
– extreme tachypnea
Risk factor for severe disease:
age < 12 wk
– preterm
– CVD
– pul
– ID

14. Acute bronchiolitis : Treatment
Supportive
Cool humidified oxygen in all hypoxemic infant
No sedative (Resp. drive)
Head & chest elevated (30o) + neck extended
Aspiration due to tachypnea (NG feeding),
in severe forms& need intubation: NPO
Trial of bronchodilator (further therapy is individualized)

15. Acute bronchiolitis : Treatment
Frequency suctioning of nasal and oral secretions often provides relief of distress or cyanosis
- CS (parenteral, oral on inhaled) have been used (conflicting studies)
Ribavirin (aerosal): in CHD – CLD
Antibiotic have no value unless co-infection of bacteria

16. Acute bronchiolitis : Treatment
No support RSV Ig during acute episode in healthy children.
Nebulizer E and Dexamethasone is not currently recommended.
Nebulized hypertonic saline (some benefit)

18. Bronchiolitis Obliterance
Chronic
Hydrochloride –Nitric oxide –sulphur oxide
Rhuematoid arthritis
SLE
GVHD
Lung transplant
Steven Jhonson
Adenovirus 7 & 21
RSV – parainfluenza -Mycoplasma

19. Bronchiolitis Obliterance
Ill, cough ,fever,dyspnea, wheez
Wax and wane
Weeks to months
Chronic lung disease in 60%

20. DX : Bronchiolitis Obliterance
Persistent wheez after transplant or viral or mycoplasma infection
Unilateral or patchy Hyperlucency -
Hyperinflation - atelectasis
V/P scan
Bronchoscopy
Chest CT
Lung biopsy

21. Bronchiolitis Obliterance
Histology
Hypertrophy -disorganizing
Destruction, Fibrosis
Oblitration of termainal bronchiol and dilation of distal bronchiol