Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology
-
The infant with persistent or recurrent wheezing during the first 2 years of life poses a diagnostic dilemma, which can be a source of anxiety to both physicians and parents. A suggested diagnostic approach to the causes of infantile wheezing is outlined. ⋯ This review discusses the diagnostic evaluation and treatment of the wheezing infant. We suggest that infant pulmonary function testing may be used as one diagnostic aid in the workup of the wheezing infant.
-
Ann. Allergy Asthma Immunol. · Mar 2001
Evaluation of Th1/Th2 ratio and cytokine production profile during acute exacerbation and convalescence in asthmatic children.
Th2-type cytokines, such as IL-4 and IL-5, are generally believed to play an important role in the pathogenesis of allergic asthma. In contrast, Th1-type cytokine, especially interferon (IFN)-gamma, is thought to have a downregulatory effect on Th2 immune response cells. Thus, the imbalance of Th1 and Th2 cells may be a key factor in relation to disease severity. ⋯ The decrease of IFN-gamma+ and IL-4+ cells detected at the single-cell level may explain the potential mechanism of convalescence from acute asthma attacks. High Th1/Th2 ratio and low IL-5 production from the PBMC of normal controls support the idea of a biased Th2 immune response in asthmatic patients.
-
Ann. Allergy Asthma Immunol. · Mar 2001
Comparative StudyAirway responses to a diluent used in the methacholine challenge test.
Inhalation of diluent is often used in performing methacholine challenge tests, but its elimination has been suggested because marked falls in FEV1 after diluent inhalation have not been documented and performing this step is time-consuming. ⋯ These data do not provide strong evidence to support either using or eliminating the diluent stage. It is clear that there are frequent and sometimes large changes in FVC and FEV1 after the inhalation of diluent containing phenol and sodium bicarbonate buffer. If a laboratory intends to report changes in airway function qualitatively (ie, positive or negative), the diluent stage may not be necessary. However, if a laboratory intends to report bronchial challenge data from inhaling methacholine in a quantitative fashion and report a continuous variable such as PC20, a diluent stage is recommended.