DEFINITION
Asthma is a chronic or acute condition involving the respiratory system in which the airways constrict, become inflamed, and are lined with excessive amounts of mucus, often in response to one or more triggers.such as:
- exposure to an environmental stimulant such as an allergen
- environmental tobacco smoke,
- cold or warm air, perfume, pet dander,
- moist air
- exercise or exertion
- emotional stress.
The Diseases Database
EPIDEMIOLOGY
Asthma has rapidly increasing prevalence, affecting up to one in four urban children
age
sex (premenstrual)
seasonality (spring or late winter?)
SYMPTOMS
"A form of bronchial disorder with three distinct components: airway hyper-responsiveness (RESPIRATORY HYPERSENSITIVITY), airway INFLAMMATION, and intermittent AIRWAY OBSTRUCTION. It is characterized by spasmodic contraction of airway smooth muscle, WHEEZING, and dyspnea (DYSPNEA, PAROXYSMAL)."
DIAGNOSIS
histopathology
radiology
NMR
laboratory tests
PATHOGENESIS
Lets assume that asthma attack depends on:
- bronchial smooth muscle contraction
- high intracellular calcium
- higher Ca influx
- lower Ca efflux
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Oxygen Toxicity and Reactive Oxygen Species: The Devil is in the Details. 2009
Vitamin D receptor-deficient mice fail to develop experimental allergic asthma. 2005
Vitamin D receptor expression by the lung micro-environment is required for maximal induction of lung inflammation. 2007
Wittke A, Chang A, Froicu M, Harandi OF, Weaver V, August A, Paulson RF, Cantorna MT.
Arch Biochem Biophys. 2007 Apr 15;460(2):306-13.
Department of Veterinary and Biomedical Science, The Center for Molecular Immunology and Infectious Disease, The Pennsylvania State University, University Park, PA 16802, USA.
Mice lacking the vitamin D receptor (VDR) are resistant to airway inflammation. Pathogenic immune cells capable of transferring experimental airway inflammation to wildtype (WT) mice are present and primed in the VDR KO mice. Furthermore, the VDR KO immune cells homed to the WT lung in sufficient numbers to induce symptoms of asthma. Conversely, WT splenocytes, Th2 cells and hematopoetic cells induced some symptoms of experimental asthma when transferred to VDR KO mice, but the severity was less than that seen in the WT controls. Interestingly, experimentally induced vitamin D deficiency failed to mirror the VDR KO phenotype suggesting there might be a difference between absence of the ligand and VDR deficiency. Lipopolysaccharide (LPS) induced inflammation in the lungs of VDR KO mice was also less than in WT mice. Together the data suggest that vitamin D and the VDR are important regulators of inflammation in the lung and that in the absence of the VDR the lung environment, independent of immune cells, is less responsive to environmental challenges.
Amino acids and asthma: a case-control study. 2004
Serotonin
Plasma serotonin, pulmonary hypertension and bronchial asthma 2002
Effect of choline chloride in allergen-induced mouse model of airway inflammation. 2007
Down-regulation of the non-neuronal acetylcholine synthesis and release machinery in acute allergic airway inflammation of rat and mouse. 2007;
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Complex picture
Cellular and Molecular Basis of Pulmonary Arterial Hypertension 2009
PATIENT RISK FACTORS
Vascular
Genetic
Acquired
Hormonal
Genetic
Acquired
Roma, 13 giu. (Adnkronos Salute) - Sugli atleti professionisti che hanno sintomi di asma, ma non hanno mai avuto problemi respiratori in precedenza, in passato si è sospettato che potessero aver abusato di farmaci anti-asma per migliorare le proprie prestazioni. Tuttavia, un nuovo studio condotto da Sergio Bonini del Cnr in collaborazione con il Coni, indica che gli sportivi di mestiere sono più a rischio di malattia proprio per il pesante allenamento cui sono sottoposti.Parlando al congresso dell'Accademia europea di allergologia e immunologia clinica a Istanbul, gli esperti italiani hanno spiegato di aver esaminato oltre mille atleti europei che hanno partecipato alle Olimpiadi di Pechino e di aver rilevato che il 15% ha avuto problemi di asma rispetto al solo 3-5% nella popolazione generale. E per Bonini una delle ragioni è che queste persone si spingono ai limiti della loro resistenza. "L'esercizio fisico intenso e prolungato - ha detto l'esperto - è un fattore di stress che riduce il numero di cellule immunitarie che proteggono dalle infezioni e aumenta quelle che causano allergie e asma". Fra gli altri motivi, anche il fatto che il respiro rapido (iperventilazione) durante lo sport, mantenuto per lunghi periodi, può causare disidratazione. Un elemento che a sua volta facilita l'improvviso restringimento delle vie aeree (broncocostrizione), 'apripista' dell'asma.
TISSUE SPECIFIC RISK FACTORS
anatomical (due its structure)
vascular (due to the local circulation)
physiopathological (due to tissue function and activity)
COMPLICATIONS