leukotriene-b4 and Bronchiolitis

To observe the effect of montelukast treatment on levels of serum leukotriene B4 and urinary leukotriene E4 in infants with bronchiolitis.. Seventy-five children who were diagnosed with bronchiolitis between June 2014 and December 2014 were randomly assigned into two groups, one with thirty-eight cases as the montelukast treatment group and another thirty-seven cases as the control group. All of the children were given routine medical treatment. The children in the montelukast treatment group were additionally given montelukast daily (4 mg once a day, for 7 days). The serum leukotriene B4 and urinary leukotriene E4 levels were measured using ELISA before and after treatment. The relationship between serum leukotriene B4 and urinary leukotriene E4 levels was analyzed by Peason correlation analysis.. After 7 days of treatment, the serum leukotriene B4 and urinary leukotriene E4 levels in the montelukast treatment and control groups were significantly reduced compared with before treatment (P<0.05). The montelukast treatment group showed significantly lower serum leukotriene B4 and urinary leukotriene E4 levels than the control group (P<0.05). The remission time of cough, wheezing and lung wheezes and the length of hospital stay in the montelukast treatment group were significantly shortened compared with the control group (P<0.05). There was a positive correlation between serum leukotriene B4 and urinary leukotriene E4 levels (r=0.723, P<0.05).. Montelukast has a reliable clinical curative efficacy for bronchiolitis in infants, possibly by decreasing serum leukotriene D4 and urinary leukotriene E4 levels.

Topics: Acetates; Bronchiolitis; Cyclopropanes; Humans; Infant; Leukotriene B4; Leukotriene E4; Quinolines; Sulfides

Respiratory syncytial virus (RSV) bronchiolitis is a very common infection in infants and, after the acute phase, a number of patients develop a reactive airway disease that lasts for years. Although the pathogenesis of the lung damage after RSV bronchiolitis is still largely unknown, previous studies suggest that leukotrienes may play an active part in it. The aim of this study was to measure leukotriene levels in the nasal lavage fluid (NLF) collected in infants during RSV bronchiolitis and 1 month later. Cysteinyl leukotrienes (Cys-LTs) and leukotriene B(4) (LTB(4)) were measured in the NLF of 22 infants with their first episode of RSV bronchiolitis and 16 healthy infants. A second NLF sample was collected to measure leukotriene levels 1 month after the acute disease. NLF Cys-LT levels were significantly higher in infants with RSV bronchiolitis than in healthy controls [950 pg/ml (285.5-2155.9) vs. 110.5 pg/ml (66.5-451.3), p = 0.01], and they remained so a month after the acute infection (p = 0.02). A subanalysis showed no difference in Cys-LTs concentrations, either between bronchiolitis infants with and without a family history of atopy, or between those with and without passive exposure to cigarette smoke. No significant difference was found between the LTB(4) levels measured in the bronchiolitis cases and the control children. Cys-LTs are significantly increased in the NLF of infants with acute RSV bronchiolitis, and remain so at 1-month follow-up, suggesting a possible role of these eicosanoids in the pathogenesis of the disease.

Topics: Bronchiolitis; Cysteine; Female; Follow-Up Studies; Humans; Infant; Leukotriene B4; Leukotrienes; Male; Nasal Lavage Fluid; Respiratory Syncytial Virus Infections; Respiratory Syncytial Virus, Human

The clinical and immunoregulatory effects of long-term macrolide antibiotic therapy for patients with chronic lower respiratory tract infections (CLRTI) were investigated. Clinical parameters and neutrophil chemotactic mediators in the epithelial lining fluid (ELF) of CLRTI patients (n = 10) were examined before and after 3 months oral administration of roxithromycin (RXM). The in vitro effects of RXM were also examined on the release of these mediators from alveolar macrophages (AM) and neutrophils. Arterial oxygen tension (p<0.05), vital capacity (VC) (p<0.001), %VC (p<0.05) and forced expiratory volume in one second (p<0.01) were improved after RXM treatment, but airway bacteria were not eradicated. Among the mediators, the levels of interleukin (IL)-8, neutrophil elastase (NE) and leukotriene B4 (LTB4) were higher in ELF than in plasma of CLRTI patients and they decreased after RXM treatment (n = 7, p<0.05 for each). RXM concentrations were significantly increased in the bronchoalveolar lavage cells of the treated patients. In in vitro experiments, RXM showed inhibitory effects on IL-8 release from AM and neutrophils. In conclusion, interleukin-8, neutrophil elastase and leukotriene B4 contribute to the neutrophilic inflammation in the airways of chronic lower respiratory tract infection patients and the clinical effects of roxithromycin may, in part, be attributable to the suppression of excess release of the chemotactic mediators from inflammatory cells.

Topics: Anti-Bacterial Agents; Bronchiectasis; Bronchiolitis; Bronchoalveolar Lavage Fluid; Chemotactic Factors; Chronic Disease; Forced Expiratory Volume; Humans; In Vitro Techniques; Interleukin-8; Leukocyte Elastase; Leukotriene B4; Macrophages, Alveolar; Middle Aged; Neutrophils; Oxygen; Respiratory Tract Infections; Roxithromycin; Vital Capacity

Leukotriene B4 (LTB4) is a potent proinflammatory mediator that may be of particular relevance to the pathology of several respiratory diseases. We have previously reported that neutrophil chemotactic mediators in the lavage fluid of patients with diffuse panbronchiolitis (DPB) consist of many components. In this study, we evaluated the effect of erythromycin (EM) on the pathogenesis of DPB, by examining the level of LTB4 in the bronchoalveolar lavage (BAL) fluid, and determining the relationship between the level and neutrophil accumulation into the respiratory tract. Pre-EM treatment neutrophil chemotactic activity (NCA) in the patients with DPB was significantly increased compared with that in five healthy nonsmoking volunteers (HVs) (p < 0.001), and the level was markedly reduced after EM treatment (p < 0.001). The amounts of LTB4, detected in the BAL fluid from the patients, was also significantly higher than those in control subjects (3.5 +/- 1.1 ng/mL vs 0.1 +/- 0.0 ng/mL, p < 0.001), and the level was significantly reduced after EM treatment (0.6 +/- 0.3 ng/mL, p < 0.01). In addition, the percent reduction of the level of LTB4 was significantly correlated with NCA (r = 0.832, p < 0.01); the reduction was also significantly correlated with neutrophil percentage before and after EM treatment (r = 0.778, p < 0.05). These findings provide evidence for the potent role of LTB4 in the respiratory tracts of patients with DPB and suggest that this lipoxygenase metabolite is involved in the recruitment of neutrophils into the airways of the patients. Our findings suggest that LTB4 is one of the most important chemotactic mediators that has a pathogenetic role in the airway damage of DPB. Erythromycin might inhibit the production of this mediator, restrict the neutrophil accumulation, modulate the excessive inflammation in the respiratory tract, and ultimately improve the pathogenesis of DPB.

Topics: Adult; Bronchiolitis; Bronchoalveolar Lavage Fluid; Chemotaxis, Leukocyte; Erythromycin; Female; Humans; Leukotriene B4; Male; Middle Aged; Neutrophils; Respiratory Function Tests