Asthma manifestations, chronic

Sensitization of the respiratory tract has followed chronic exposure to fumes or dust of TETA, manifested by bronchial asthma. One worker developed asthma after working with an epoxy resin-TETA formulation for 6 months in a job laminating aircraft windows. In an environmental chamber, the worker developed flulike symptoms and asthmatic breathing after simulating the job conditions for 2 hours with the resin-TETA mixture. Similar exposure to the resin alone did not produce the symptoms. 

In conclusion, the ARIA WHO workgroup emphasized the link between rhinitis and asthma and declared rhinitis a major chronic respiratory disease and a risk factor for the development of lower airway disease. It is therefore critical to treat both airway manifestations in a combined strategy, and immunotherapy has been proven to be a suitable treatment when patients are selected carefully. 

Atopic dermatitis is a chronic inflammatory skin disorder that affects the epidermis and is characterized by eczema and itching. Two percent of the adult population is afflicted by atopic dermatitis, often with the earliest manifestation first appearing in childhood.The peak incidence occurs during the fourth or fifth decade.There is a femily tendency as well as a predisposition to allergy and asthma. Periorbital inflammation is a common manifestation of atopy. Acute manifestations include exudative lesions, erythema, and edema. Chronic manifestations include dry scaly lesions with lichenification. 

Although inflammation is essentially a normal defensive mechanism (a reaction to tissue injury, infection, inhalation of foreign proteins), the manifestations may be so serious and inappropriate or Involve such discomfort, that treatment with antiinflammatory agents is required. Inflammatory conditions can be acute (as in insect stings) or chronic (chronic asthma, dermatitis and other skin conditions, rheumatoid conditions). A wide range of drugs may be used to treat one or other inflammatory condition, and potential toxicity in relation to the medical condition is an important determinant of choice. 

In humans, exposure to low concentrations, 0.1-0.2 ppm, can result in irritation of the eyes, nose, and mucous membranes. Acute exposure to higher concentrations can cause bronchitis, pneumonitis, headache, sleeplessness, pulmonary edema, and sometimes an asthma-like syndrome. Chronic exposure can result in wheezing, coughing, shortness of breath, and chest congestion. Such effects may be manifested from inhalation of 0.02-0.05 ppm of the diisocyanate over a period of time. 

Clinical Manifestations. The initial manifestations of bronchial asthma can occur at any age. However, the vast majority of extrinsic asthmatics first note symptoms as children or young adults, and those who appear in later decades often have had some earlier manifestation of atopy or allergy. On the other hand, intrinsic asthma generally occurs after the age of 30. Other differences between these two types of asthmatics are noted in Table II. Any individual patient may demonstrate some overlap of these features. For example, the extrinsic asthmatic may be continuously exposed to the specific antigenCs) and, therefore, have symptoms chronically. 

Bronchial asthma is characterized by an increased responsiveness of the trachea and bronchi to various stimuli and is manifested by a widespread narrowing of the airways that changes in severity either spontaneously or as a result of therapy (91). Chronic bronchitis is defined as a condition with chronic or recurrent bronchial hypersecretion, cough and expectoration during at least 3 months for at least 2 successive years (92). Chronic bronchitis is often associated with chronic airways obstruction with minimal reversibility it is then called chronic obstructive pulmonary disease (COPD). Chronic airways obstruction in COPD is believed to be caused by either emphysema or irreversible obstructive changes in the peripheral airways, or both. There is an overlap between asthma and COPD, and many patients may have features of both diseases (93). Asthma is considered an important risk factor for the development of COPD. Bronchial hyperresponsiveness is a hallmark of asthma, whereas its importance in COPD is more obscure. Airway inflammation is a key factor for the development of bronchial hyperresponsiveness (94). Table 4 shows the main pathophysiological features of airways obstruction in asthma, chronic bronchitis, and emphysema. 

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