As the weather changes, the respiratory clinic is inundated with patients with a “cold” and cough. These people often have a normal temperature, no sore throat, but they just cough a lot, take a lot of cold medicine, antibiotics, cough medicine, and even intravenous rehydration, but the chest X-ray and blood tests are normal. Why is this?
Among the many patients with cough, doctors pay extra attention to chronic cough. After excluding organic diseases, there are numerous causes of chronic cough, the most common being cough variant asthma, a specific type of asthma with chronic cough as the main or only clinical manifestation. Cough variant asthma must be treated with long-term standardized therapy in order for the cough to be cured and for symptoms such as shortness of breath and chest tightness to be prevented.
Cough variant asthma can easily be misdiagnosed as a cold or bronchitis. An experienced respiratory physician can initially determine if cough variant asthma is suspected by asking patients about their symptoms and past medical history. Cough variant asthma does not have the shortness of breath or chest tightness typical of asthma, but the cough has the following characteristics: it is mostly a dry paroxysmal cough with little sputum, often recurring at night or in the early morning. The cough is easily triggered or aggravated after a cold or by exposure to cold air, dust, fumes, paint or other irritating odors, and in some patients the cough worsens after exercise; the cough occurs repeatedly for several years, mostly in spring and autumn, or lasts for several months without healing. These patients are often allergic, suffer from allergic rhinitis (paroxysmal nasal itching, sneezing, clear nasal discharge), allergic dermatitis, and other allergies, or have a family history of allergies.
In patients with suspected cough variant asthma, spirometry is a necessary objective indicator to confirm the diagnosis. Patients with cough that is not cured for a long time, or those with recurrent coughing episodes, should be seen at a respiratory specialty or specialist hospital for timely diagnosis or exclusion of asthma and treatment.
Five major clinical manifestations of allergic asthma.
1. Most attacks are seasonal, with spring and autumn being the most common.
2. In adults with cough asthma, the age of onset is higher than that of typical asthma, with about 13% of patients older than 50 years old and more common in middle-aged women, while in childhood, cough may be the only symptom of asthma, or even a precursor to the development of bronchial asthma.
3, Positive bronchial excitation test, when a positive reaction occurs, can appear similar to the irritating cough at the onset, suggesting the presence of airway hyperresponsiveness; positive reversibility test for airway obstruction.
4.More often there is a clearer family history of allergy or a history of allergic diseases in other areas, such as allergic rhinitis, eczema, etc.
5.The clinical manifestations are mainly long-term persistent dry cough, often induced after exercise, inhalation of cold air, upper respiratory tract infection, intensified at night or in the early morning, no croup on physical examination, lung function impairment between normal and typical asthma, skin allergen test can be positive.
Seven characteristics of variant asthma.
1. Chest X-ray shows normal or increased lung texture but no other organic changes.
2. Persistent or recurrent coughing attacks for more than one month, often occurring at night or in the early morning, aggravated by exercise, with little sputum;
3. Laboratory tests or other examinations show no obvious signs of infection or long-term antibiotic treatment is ineffective;
4.The use of bronchodilators can reduce the attacks;
5.Asthma is seasonal, mostly seen in spring and autumn and recurrent attacks;
6.Exercise, cold air, allergens or viral infections can trigger asthma attacks;
7, there is a personal history of allergy, that is, with a history of eczema, urticaria, allergic rhinitis, etc., can also be found in the family allergy history.
The diagnostic criteria for allergic asthma (CVA) are as follows.
1. Recurrent coughing attacks for 1 month, with worsening cough at night or early morning.
2, No clear evidence of inflammation and ineffective antibiotic treatment.
3.The use of bronchodilators can lead to relief of coughing episodes (basic diagnostic condition)
4, there is a personal history of allergy or family history of allergy treatment mainly inhaled beta2 agonists, beclomethasone propionate, butyldehydrexone, controlled-release tantalones, etc.
5.The disease is caused by hereditary allergic body allergy to the environment.
6.Pulmonary function test, bronchial excitation test is positive.
CVA treatment principle is the same as asthma treatment. Most patients can be treated with small doses of glucocorticoids plus beta agonists, and oral glucocorticoid therapy is rarely needed. The duration of treatment should be at least 6-8 weeks.
1.Anti-allergic drugs such as paracetamol, ketotifen, etc. are effective for variant asthma.
2.Glucocorticoids such as prednisone and pramipexole aerosol can be applied during asthma attack.
3.Cough and asthma medications such as aminophylline, methotrexate, etc. can be applied.
4.Anti-allergic drugs can generally be used: fenagan, ketotifen; preventive drugs such as bronchitis vaccine tablets can also be used.