Relationship between leukotriene C4 and an uteroglobin-like protein in nasal and tracheobronchial mucosa of children. Implication in acute respiratory illnesses

Secretions from the nose and nasopharynx (NPS) are more readily accessible than tracheobronchial secretions (TBS) for clinical investigations, but it is unclear whether changes in mediator release in the nasopharynx reflect similar changes in the tracheobronchial tree. In order to clarify this question, NPS and TBS were taken from 20 children with tracheotomy and tested for the presence of leukotriene C4 (LTC4) and uteroglobin-like protein (UTG-LP). LTC4 and UTG-LP were measured both when the children were healthy and when they had clinical evidence of an acute respiratory tract illness. The mean concentration of LTC4 in NPS and TBS increased during illness although the mean concentration in NPS was significantly higher than in TBS during respiratory illness. In healthy children UTG-LP was detected only in TBS. During acute respiratory illness the concentration of UTG-LP in TBS decreased but remained significantly higher than in NPS. Data presented in this study indicate that changes in the LTC4 concentration in NPS appear to reflect changes in LTC4 concentration in TBS although the levels of LTC4 in NPS were significantly higher than in TBS. An inverse correlation between the concentrations of LTC4 and UTG-LP in NPS and TBS was demonstrated.