Clinical Researich Of Montelukast On Treating Recurrent Bronchiolitis

ObjectiveBronchiolitis is a common disease in infant,50%-80% of which is caused by respiratory syncytial virus(RSV),and many are infants less than 6 months old. Clinical symptoms of paroxysmal cough and wheezing, is the state of airway hyper responsiveness(AHR) in performance. About 50% to 70% of infants who are bronchiolitis may have recurrent wheezing.eventually develop into bronchial asthma.The incidence is significantly higher than in normal children, which is harm to the child's physical and mental health seriously. Cysteinyl leukotriene(CysLT) are derived from arachidonic acid(AA) through the 5-lipoxygenase(5-LO) pathway, which are composed of leukotriene C4(LTC4),leukotriene D4(LTD4)and leukotriene E4(LTE4). Cysteinyl leukotriene (CysLT) is the key media in airway inflammation,which have many biological activity:cause smooth muscle constriction, increase airway mucus secretion,promote eosinophil recruitment and activation,increase microvascular permeability, promote the accumulation of inflammatory cells in airway.These reasons altoghter cause the airway hyper responsivenes,then the The corresponding clinical symptoms can be seen. There are several ways which can evaluate the overall level of CysLT in vivo,but total CysLT production is quantified by urinary LTE4 levels,which is simple and noninvasive.Because urinary leukotriene E4 is the major metabolite of the CysLT in vivo,and excretes at a stable ratio of 4%-7%,it can be detected to evaluate the CysLT production in vivo. Nowadays,the role of CysLT in asthma has been affirmed, however, bronchiolitis have much in common with bronchial asthma in the pathogenesis of bronchiolitis, pathology, clinical manifestations. We speculate that cysteinyl leukotriene also play an important role in bronchiolitis. The effect of Cysteinyl leukotriene receptor antagonist(LTRA) for the treatment of bronchial asthma is significant.It is a treatment in GINA(Global initiative for asthma)2006. In this study, we detected the children with bronchiolitis by the levels of urinary LTE4, According to the study result,Cysteinyl leukotriene receptor antagonist may be used in the therapy of bronchiolitis. It will also inspect that whether the children with bronchiolitis evolve into bronchial asthma in the future and clue on the time of therapy.MothodsWe detected the urinary LTE4 level by enzyme-linked immunosorbent assay (ELISA) method.100 children (3-24months) with bronchiolitis were divided randomly into the montelukast group(60) and the routine group(40).The montelukast group was given the synthetic therapy and montelukast, another Group was only given the synthetic therapy.Detect the expression of urinary LTE4 before and after the therapy.Peripheral blood was used to determine eosinophils count(EC) in acute bronchiolitis cases.We observe the time needed to relieve children's asthma. All children were fllowed up 6 months.At the same time after discharge from hospital records of two groups of re-hospitalization rate.ResultUrinary LTE4 in children with bronchiolitis was higher than normal children(P<0.05) before thetherapy,and the expression of urinary LTE4 was also more decreased than the routine group(P<0.05),which the expression was higher than normal children. Urinary leukotriene E4 level is significantly higher in severe group(P<0.01); Urinary leukotriene E4 level of atopy positive infants with bronchiolitis is significantly higher than atopy negative infants(P<0.01); The concentration of urinary LTE4 of mycoplasma pneumoniae (MP)-IgM positive was higher than that of MP-IgM negative (P<0.05), but RSV-IgM positive group and RSV-IgM negative group had no significant difference(P>0.05).There is no significant correlation between the levels of urinary leukotriene E4 and EC for acute bronchiolitis(P>0.05).Two cases of main symptoms and signs and duration of hospitalization time:children's cough and lung physical sign duration and hospitalization time in montelukast group were shorter than that of routine treatment group, it was statistically significant differences(P<0.01).The number of children who gasped and the frequency of the gasping in montelukast group were lower than that of the routine group. Conclusions:1. Application of ELISA for determination of urinary levels of LTE4 are more rapid,accurate,easy and noninvasive,and the results can reflect the overall level of CysLT in vivo the body and are easy and noninvasive.2.The level of urinary LTE4 in acute bronchiolitis patients increases and remains high in convalescent stage;Higher urinary LTE4 level in acute bronchiolitis cases indicates that urinary LTE4 level is related to the severityof the disease; CysLT is an important mediator of inflammation that may influence the prognosis of atopy positive infants with bronchiolitis;EC is not a good index to present the airway inflammation of infants with bronchiolitis.3. CysLT play an important role in the pathogenesis of bronchiolitis.4.Montelukast can lower the urinary LTE4 in children with bronchiolitis, and produce a marked effect on antinflammation mechanism in bronchiolitis. Orally taken montelukast is effective and has less adverse reaction for infants and young children after bronchiolitis prevent recurrent asthmatic wheezing in and ought to be recommended.We presume that the montelukast could be intervention earlier and decrease morbility。...