Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology
-
The unpredictability of anaphylactic reactions and the need for immediate, often improvised treatment will make controlled trials impracticable; other means must therefore be used to determine optimal management. ⋯ Immediate recognition of anaphylaxis, early use of adrenaline, inhaled beta agonists and other measures are crucial for successful treatment. Nevertheless, a few reactions will be fatal whatever treatment is given; optimal management of anaphylaxis is therefore avoidance of the cause whenever this is possible. Predictable cross-reactivity between the cause of the fatal reaction and that of previous reactions had been overlooked. Adrenaline overdose caused at least three deaths and must be avoided. Kit for self-treatment had proved unhelpful for a variety of reasons; its success depends on selection of appropriate medication, ease of use and good training.
-
Mast cells are positioned in the asthmatic airways so that they are able to respond to the inhaled environment. During active disease, the cells are primed to secrete an array of preformed and newly generated inflammatory mediators including histamine, neutral proteases and heparin sulphate, prostaglandins and cysteinyl leukotrienes as well as an array of cytokines and chemokines that are involved in leucocyte recruitment and activation. ⋯ The recent discovery of novel inhibitory pathways involving inhibitory motifs (ITIMS) on critical cell surface signalling molecules has opened up new possibilities for preventing mast cell activation. Future research will focus on more effective ways for inhibiting the mast cell's contribution to asthma and understanding what role this unique cell has in the pathogenesis of airway wall remodelling.
-
The paediatric asthma guidelines have been successful in providing a uniform approach to the management of asthma for the medical profession as a whole. Unfortunately, the guidelines were generated without input from patients themselves and consequently do not consider issues that are important to patients such as a preference for oral treatment. Asthma is a heterogeneous group of conditions and the guidelines do not sufficiently define subgroups of patients and their particular needs. ⋯ Anti-histamines and leukotriene receptor antagonists may be interesting as interventions in that respect. Two important unresolved issues are to understand what drives remodelling and inflammation, and to look at early life origins of asthma. These approaches may provide effective therapeutic targets and, ultimately, a means of prevention.
-
Review
Clara cell secretory protein (CC16): characteristics and perspectives as lung peripheral biomarker.
Clara cell protein (CC16) is a 15.8-kDa homodimeric protein secreted in large amounts in airways by the non-ciliated bronchiolar Clara cells. This protein increasingly appears to protect the respiratory tract against oxidative stress and inflammation. In vitro, CC16 has been shown to modulate the production and/or the activity of various mediators of the inflammatory response including PLA2, interferon-gamma and tumour necrosis factor-alpha. ⋯ In humans, a polymorphism of the CC16 gene, localized to a region linked to airway diseases, has recently been discovered in association with an increased risk of developing childhood asthma. Finally, CC16 also presents a major interest as a peripheral marker for assessing the integrity of the lung epithelium. The determination of CC16 in serum is a new non-invasive test to detect Clara cell damage or an increased epithelial permeability in various acute and chronic lung disorders.
-
Airway hyperresponsiveness to histamine is a hallmark of asthma, and histamine inhalation reproduces asthma symptoms. Plasma histamine concentrations are elevated during the early and late responses to inhaled allergens, and may also increase during spontaneous acute asthma episodes. ⋯ In moderate persistent asthma, clinical benefits of H1 antagonists are apparent, but may not be worth the potential risks of the higher-than-usual doses required. When mild seasonal asthma and allergic rhinitis coexist, however, relief of rhinitis symptoms with H1 antagonists administered in ordinary dose is associated with significant improvement in asthma symptoms.