Lung function measurements in children - copsac
Lung function measurements in children - copsac
Lung function measurements in children - copsac
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Cl<strong>in</strong>ical manifestations<br />
RSV <strong>in</strong>fection can be spread from an <strong>in</strong>fected person up to three weeks after symptom<br />
debut by send<strong>in</strong>g virus-conta<strong>in</strong><strong>in</strong>g droplets <strong>in</strong>to the air when cough<strong>in</strong>g or sneez<strong>in</strong>g. The<br />
droplets rema<strong>in</strong> contagious on environmental surfaces more than 6 hours and can <strong>in</strong>fect<br />
a person when it comes <strong>in</strong> contact with mouth, nose or eye. Common symptoms of RSV<br />
<strong>in</strong>fection are upper respiratory <strong>in</strong>fection and coryza. Most recover from RSV <strong>in</strong>fection<br />
with<strong>in</strong> 1 to 2 weeks. However, <strong>in</strong> 25-40 % of the primarily <strong>in</strong>fected <strong>in</strong>fants a RSV<br />
<strong>in</strong>fection manifests as a lower respiratory tract <strong>in</strong>fection, bronchiolitis or pneumonia.<br />
Infants with bronchiolitis have tachypnea, wheezes, chest retractions and <strong>in</strong> the<br />
youngest <strong>in</strong>fants risk of apnea (69, 85). Almost all <strong>children</strong> are <strong>in</strong>fected with the virus<br />
by their second birthday, but only a small percentage develops severe disease.<br />
Asthma <strong>in</strong> childhood<br />
Asthma <strong>in</strong> young <strong>children</strong> is associated with high morbidity and the prevalence is<br />
<strong>in</strong>creas<strong>in</strong>g (86). Approximately 7% of Danish school<strong>children</strong> have asthma and 15-20 %<br />
of preschool <strong>children</strong> have episodes of asthmatic symptoms. This is the most common<br />
cause of hospitalization of young <strong>children</strong> <strong>in</strong> Denmark (87).<br />
Def<strong>in</strong>ition<br />
Asthma is a chronic <strong>in</strong>flammatory disorder of the airways. The mechanism <strong>in</strong>volves<br />
several <strong>in</strong>flammatory cells (mast cells, eos<strong>in</strong>ophils, Th2 etc.) which release mediators<br />
that contribute to airway narrow<strong>in</strong>g: the airway smooth muscle contracts; <strong>in</strong>creased<br />
microvascular leakage lead to airway oedema; mucus hypersecretion; and airway<br />
thicken<strong>in</strong>g (“remodell<strong>in</strong>g”).<br />
Asthma has significant genetic and environmental components, but s<strong>in</strong>ce its<br />
pathogenesis is not clear, much of its def<strong>in</strong>ition is descriptive (86).<br />
Cl<strong>in</strong>ical manifestations and diagnosis<br />
The chronic <strong>in</strong>flammation is associated with airway hyperresponsiveness that leads to<br />
recurrent episodes of wheez<strong>in</strong>g, breathlessness, chest tightness, and cough<strong>in</strong>g,<br />
particularly at night or <strong>in</strong> the early morn<strong>in</strong>g. Follow<strong>in</strong>g symptoms are highly suggestive<br />
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