Corpi estranei endobronchiali (contributo clinico).

Viene riportata l'esperienza di estrazione di corpi estranei in un gruppo di bambini

Late asthmatic reactions to toluene-diisocyanate are associated wlth airway inflammation.

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Pathogenesis of late asthmatic reactions induced by exposure to isocyanates.

The importance of airways inflammation for the development of bronchial hyperresponsiveness and for exacerbation of asthma was investigated in subjects with occupational asthma. We examined subjects sensitized to isocyanates, a small molecular weight compound that causes occupational asthma. Studies in asthmatic subjects sensitized to toluene diisocyanate (TDI) demonstrated that late, but not early, asthmatic reactions induced by TDI were associated with an acute increase in bronchial responsiveness, and with a marked infiltration of neutrophils and a slight infiltration of eosinophils into the airways, both prevented by steroids. As the late asthmatic reactions and the increase in responsiveness induced by TDI were prevented by steroids, but not by indomethacin, we speculated that cell membrane phospholipid metabolites, which are inhibited by steroids but not by indomethacin, may be involved in TDI induced hyperresponsiveness. The results of these studies suggest that bronchial hyperresponsiveness and exacerbation of asthma may be related to inflammation of the airways and that cell membrane phospholipid metabolites may be involved

Leukotriene B4 and late asthmatic reactions induced by toluene diisocyanate.

We investigated whether leukotriene B4 (LTB4) is released from the lungs of sensitized subjects during asthmatic reactions induced by toluene diisocyanate (TDI). We examined three groups of TDI-sensitized subjects, one after no exposure to TDI, the second 8 h after an exposure to TDI that caused an early asthmatic reaction, and the third 8 h after an exposure to TDI that caused a late asthmatic reaction. We analyzed bronchoalveolar lavage (BAL) fluid by reverse-phase high-performance liquid chromatography and by specific radioimmunoassay. The mean concentration of LTB4 was higher [0.31 +/- 0.09 (SE) ng/ml, range 0.15-0.51] in BAL fluid of sensitized subjects who developed a late asthmatic reaction than in BAL fluid of subjects who developed an early asthmatic reaction (0.05 +/- 0.04 ng/ml, range 0-0.224), and no LTB4 was detectable in the control subjects. We also performed BAL 8 h after TDI exposure on four TDI-sensitized late-dual reactors who were on steroid treatment. In this group of subjects no LTB4 was detectable. These results suggest that LTB4 may be involved in late asthmatic reactions induced by TDI

Mast cells in the airway mucosa and rapid development of occupational asthma induced by toluene diisocyanate.

We examined lobar bronchial biopsies taken from 18 subjects with occupational asthma induced by toluene diisocyanate (TDI) and from nine nonasthmatic control subjects. Two groups of asthmatics were identified on the basis of the duration of exposure to TDI before the onset of symptoms of asthma. Group A (n = 8) developed asthma after 2.4 +/- 0.4 yr of exposure to TDI, and Group B (n = 10) developed asthma after 21.6 +/- 3.1 yr of exposure to TDI. Both groups of asthmatic subjects had increased numbers of inflammatory cells in the airway mucosa compared with subjects in the nonasthmatic control group. Comparison between Groups A and B showed that subjects who developed asthma after short-term exposure had a significantly increased number of mast cells both in epithelium and in lamina propria than did subjects who developed asthma after long-term exposure to TDI (p < 0.01). Interestingly, the numbers of mast cells both in the epithelium (rs = -0.52, p < 0.05) and in the lamina propria (rs = -0.81, p < 0.001) were inversely correlated with the length of exposure to TDI before the onset of asthma. In conclusion, subjects who develop asthma after short-term exposure to TDI have an increased number of mast cells in the airway mucosa, suggesting that these cells may be associated with individual susceptibility differences to offending agents

Il lavaggio broncoalveolare nell'asma.

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Leukotriene B4 and late asthmatic reactions induced by toluene diisocyanate.

We investigated whether leukotriene B4 (LTB4) is released from the lungs of sensitized subjects during asthmatic reactions induced by toluene diisocyanate (TDI). We examined three groups of TDI-sensitized subjects, one after no exposure to TDI, the second 8 h after an exposure to TDI that caused an early asthmatic reaction, and the third 8 h after an exposure to TDI that caused a late asthmatic reaction. We analyzed bronchoalveolar lavage (BAL) fluid by reverse-phase high-performance liquid chromatography and by specific radioimmunoassay. The mean concentration of LTB4 was higher [0.31 +/- 0.09 (SE) ng/ml, range 0.15-0.51] in BAL fluid of sensitized subjects who developed a late asthmatic reaction than in BAL fluid of subjects who developed an early asthmatic reaction (0.05 +/- 0.04 ng/ml, range 0-0.224), and no LTB4 was detectable in the control subjects. We also performed BAL 8 h after TDI exposure on four TDI-sensitized late-dual reactors who were on steroid treatment. In this group of subjects no LTB4 was detectable. These results suggest that LTB4 may be involved in late asthmatic reactions induced by TDI

Importance of airway inflammation for late asthmatic reactions induced by toluene diisocyanate in sensitized subjects.

To determine the importance of airway inflammation for late asthmatic reactions and increased airway responsiveness induced by TDI, we investigated whether late asthmatic reactions and increased responsiveness induced by TDI are associated with airway inflammation and whether steroids prevent them by modifying the inflammatory response within the airways. We measured FEV1 before and at regular intervals after exposure to TDI and performed dose-response curves to methacholine and bronchoalveolar lavage 8 hr after TDI in two subjects with previously documented late asthmatic reaction; then we repeated the same procedure a few weeks after treatment with steroids. Airway responsiveness and polymorphonuclear cells were increased in both subjects after the late asthmatic reaction; treatment with steroids prevented late asthmatic reaction and the increase in airway responsiveness and polymorphonuclear cells in bronchoalveolar lavage. These results suggest that late asthmatic reaction induced by TDI may be caused by airway inflammation