Λεξικό .. Bronchiolitis

Bronchiolitis is a distressing, potentially life-threatening respiratory condition that affects young babies. Around 2-3% of all infants younger than 1 year are admitted to hospital with bronchiolitis, usually during the seasonal epidemic. The majority of these infants are infected with respiratory syncytial virus and all have an intense inflammatory response in their airways. Although most infants recover, they have an increased risk of recurrent wheezing. Although bronchiolitis is common, little is known about what causes infants to be susceptible. Diagnostic interventions have little effect on clinical outcome, and apart from supportive measures, there is no specific treatment. Bronchiolitis therefore presents an intriguing clinical conundrum and a major challenge to researchers. High quality clinical studies are needed to clarify assessment of disease severity and criteria for hospital admission, particularly the use of pulse oximetry and chest radiography. Careful mapping of the inflammatory pathways in the pathogenesis of bronchiolitis should lead to development of new therapies to alleviate symptoms[1].

In children with bronchiolitis, 2 clinical factors, age and number of previous wheezing episodes, are linked to inflammatory (atopy-related factors) and virologic risk factors of asthma (rhinovirus-associated disease). According to current US and UK guidelines, bronchiolitis includes wheezing children <24 months of age. Our observations suggest that the clinical definition should include only children with their first episode of wheezing [2]. 25 to 32 per cent of infants with bronchiolitis subsequently developed asthma, it was suggested that the measurement of serum IgE level may be helpful in identifying those infants with sporadic bronchiolitis who will subsequently develop asthma [3].

Croup and acute bronchiolitis are common forms of virally induced respiratory disease in infancy and early childhood. There is good evidence that corticosteroids can ameliorate disease severity and alter the natural history of symptoms in patients who have croup and that temporary symptomatic benefit can be obtained from the use of nebulized adrenaline. The principle weakness when reviewing therapeutic interventions for acute bronchiolitis is the lack of a clear diagnostic test or definition. Current evidence suggests that oxygen is the only useful pharmacologic agent for correcting hypoxia [4].

References

1. Smyth RL, Openshaw PJ. Bronchiolitis. Lancet. 2006 Jul 22;368(9532):312-22 .Comment in:Lancet. 2006 Sep 16;368(9540):988.
2. Jartti T, Lehtinen P, Vuorinen T, Ruuskanen O. Bronchiolitis: age and previous wheezing episodes are linked to viral etiology and atopic characteristics. Pediatr Infect Dis J. 2009 Apr;28(4):311-7. 3. Orgel, H.A.: Genetic and developmental aspects of IgE. Ped. Cl. of N. Am. 22, 1:17-32, 1975.
 

4. Everard ML. Acute bronchiolitis and croup. Pediatr Clin North Am. 2009 Feb;56(1):119-33,