Bronchiolitis

definition

acute inflammatory illness of the small airways of the lower respiratory tract

aetiology

viral

RSV

parainfluenza

influenza

<6mo

prematurity

heart or lung disease

NMD

immunodeficiency

pathophysiology

bronchiolar injury and consequent interplay between inflammatory and mesenchymal cells can lead to diverse pathologic and clinical syndromes

excessive mucus production

lymphocytic infiltration leading to submucosal oedema

inflammation, oedema, and debris result in obstruction of the bronchioles, leading to hyperinflation, increased airway resistance, atelectasis, and VQ mismatching

incidence

very common in < 2 y

seasonal

clinical

prognosis

self-limiting

7-10 day course

morbidity and mortality mostly in younger than 2

history

day 1-3

low grade fever

rhinorrhea

cough

day 4-6

respiratory distress

tachypnoea

hypoxia

examination

tachypnoea

hypoxia

intercostal recession

crackles or coarse breath sounds +/- wheeze

diagnosis

clinical

ancillary

?CXR - r/o pneumonia

nasopharyngeal aspirate - RSV

treatment

supportive

hydration

suctioning

supplemental 02

?bronchodilators if Hx or strong FHx of asthma

hospitalise if signs of severe illness are present

complications

ARDS

bronchiolitis obliterans

congestive heart failure

secondary infection