leukotriene-e4 and Respiratory-Syncytial-Virus-Infections

The persistence of wheezing after early wheezing episodes in infancy may be related to the virus involved and to the type of inflammation during the initial wheezing. The role of mast cell activation and leukotriene secretion in wheezing, and the relation to outcome, is not known. Our objective was to study markers of mast cell activation and leukotriene secretion from wheezing infants, and the relation to respiratory syncytial virus (RSV) infection and persistent wheezing. Urinary 9alpha,11beta-PGF(2), a marker of mast cell activation, and urinary leukotriene E4 were measured in 106 infants hospitalized for wheezing during their first year of life. Results were related to the presence of RSV infection and the persistence of wheezing at follow-up 20 months later. Levels of 9alpha,11beta-PGF(2) were higher in infants positive for RSV than in those with RSV negative wheezing, but both groups had higher levels than controls. Leukotriene E4 levels were higher in wheezing infants than in controls. Urinary 9alpha,11beta-PGF(2) levels were higher in infants with transient compared with persistent wheezing. We found a positive correlation between 9alpha,11beta-PGF(2) and leukotriene E4, strongest in infants with RSV negative disease and in infants with persistent wheezing. The results suggest that mast cells play an important role in infant wheezing, and may be a major source of leukotriene secretion in these infants. Mast cell activation and leukotriene secretion were not associated with persistent wheezing.

Topics: Eosinophil-Derived Neurotoxin; Eosinophils; Female; Humans; Infant; Leukocyte Count; Leukotriene E4; Leukotrienes; Male; Mast Cells; Regression Analysis; Respiratory Sounds; Respiratory Syncytial Virus Infections

Respiratory syncytial virus (RSV) infection is a risk factor for the development of asthma. It is very hard to distinguish bronchiolitis with respiratory virus infection from allergic asthma at first wheezing attack in early childhood. To distinguish wheezing children with RSV bronchiolitis from asthmatic children, we measured leukotriene E(4)(LTE(4)) in urine and ECP in nasopharyngeal aspiration (NPA) at first day of admission with wheezing attack. Thirty-two non-atopic children younger than the age of 3 yr with RSV induced bronchiolitis, 35 atopic asthmatic children with/without respiratory viral infection, and 23 children who exhibited no evidence of atopy, asthma, or virus infections as controls were selected in this study. We measured urinary LTE(4) and ECP level in NPA from subjects. Urinary LTE(4) concentrations in children with asthma were significantly higher than urinary LTE(4) in bronchiolitis and in controls (240.8 +/- 129.8 vs. 162.8 +/- 73.9 vs. 85.1 +/- 31.6 pg/ml). Children with RSV infection demonstrated higher urinary LTE(4) levels compared to children without RSV infection among asthmatic children. ECP in NPA was significantly correlated with urinary LTE(4) (r = 0.57, p < 0.01) in children entered this study who had detectable levels for both LTE(4) and ECP. In summary, Urinary LTE(4) concentrations may be suggested to useful mediators for differential diagnosis of wheezy diseases in early childhood. RSV infection also is associated with synergizing LT biosynthesis and this study demonstrated ECP in NPA was significantly correlated with urinary LTE(4) and may suggest that cysteinyl leukotriene initiate the production of ECP in early childhood, which could contribute to the development of wheeze.

Topics: Asthma; Bronchiolitis; Case-Control Studies; Child, Preschool; Diagnosis, Differential; Eosinophil Cationic Protein; Female; Humans; Infant; Leukotriene E4; Male; Nasopharynx; Respiratory Sounds; Respiratory Syncytial Virus Infections; Respiratory Syncytial Virus, Human; Suction

Respiratory syncytial virus (RSV) infection is the most common cause of bronchiolitis in infants and an important risk factor for the development of recurrent wheezing and asthma. Cysteinyl leukotrienes were implicated in the pathophysiology of these diseases, and are being targeted for their diagnosis and therapy. We measured urinary leukotriene E4 (LTE4) in infants with RSV bronchiolitis in comparison with controls without respiratory infection, and investigated whether medical and family history, age, and passive exposure to tobacco smoke are related to urinary leukotriene excretion. We studied 33 infants with bronchiolitis and 25 controls, 1-12 months of age. Demographic and historical data were obtained from informed-consent forms and questionnaires completed by the parents. RSV was detected in nasal secretions by enzyme-linked immunoassay. Urine samples were collected on day of admission and were analyzed for LTE4 with an enzyme-linked immunoassay. Urinary LTE4 was 8-fold higher in infants with bronchiolitis than in controls. Leukotriene excretion was significantly higher in infected infants <6 months of age with a medical history of eczema or dry cough and/or family history of asthma. Multivariate analysis revealed that eczema and dry cough are independently associated with high LTE4 excretion during bronchiolitis. Exposure to tobacco smoke did not affect urinary LTE4. Our study shows that leukotriene synthesis during bronchiolitis is particularly elevated in younger infants with an atopic/asthmatic background. Urinary LTE4 may become a valuable, noninvasive marker for the identification of patients who will benefit most from therapy with leukotriene modifiers for management of bronchiolitis.

Topics: Age Factors; Asthma; Bronchiolitis; Enzyme-Linked Immunosorbent Assay; Female; Humans; Hypersensitivity; Infant; Leukotriene E4; Male; Respiratory Syncytial Virus Infections; Tobacco Smoke Pollution

We prospectively studied the levels of eicosanoids in intubated patients with severe bronchiolitis and compared them to electively intubated non-infected infants. LeukotrieneE(4) (LTE(4)), leukotrieneB(4) (LTB(4)), and prostaglandinE(2) (PGE(2)) levels were significantly increased (P <.01) from endotracheal (ET) aspirates of infants with bronchiolitis compared with controls, as were urinary LTE(4) levels (P <.001). We conclude that eicosanoids are increased in the tracheal aspirates and urine of children with bronchiolitis.

Topics: Acute Disease; Bronchiolitis, Viral; Case-Control Studies; Child, Preschool; Dinoprostone; Female; Humans; Infant; Intubation, Intratracheal; Leukotriene B4; Leukotriene E4; Male; Prospective Studies; Respiratory Syncytial Virus Infections

The levels of leukotriene E4 (LTE4) of the urine were determined in 24 pediatric patients with infectious diseases due to respiratory syncytial virus (RSV), i.e., bronchitis, pneumonia, and bronchiolitis, and compared with those in controls without allergic disease. The level for LTE4 of the acute-phase urine was 620+/-562 pg/mg. cr in the pediatric patients infected with RSV, being significantly higher than 190+/-67 pg/mg. cr in controls (P<0.005). The levels for LTE4 of the urine in the recovery phase showed a tendency toward decrease, as compared to those in the acute phase. However, there was no significant difference in the level for LTE4 of the acute-phase urine between the presence and the absence of each of the following conditions: expiratory wheezing; the association of pneumonia; family history of allergic diseases; the association of atopic dermatitis; and a past history of expiratory wheezing. An allergological study also revealed that there was no significant difference in LTE4 level between the presence and the absence of peripheral eosinophilia or between the presence and the absence of the high total level for IgE of the serum or positivity for the specific IgE level in the serum. These results suggest that LT is involved with the pathological conditions of RSV infection, but there are no direct relation between atopic diathesis or expiratory wheezing and the amounts of LT production.

Topics: Bronchiolitis; Bronchitis; Child, Preschool; Female; Humans; Hypersensitivity; Infant; Leukotriene E4; Male; Pneumonia, Viral; Respiratory Syncytial Virus Infections