Chronic cough

Introduction Cough is a protective reflex that has the effect of removing secretions accumulated in the airway and preventing foreign bodies from entering the body; cough is also a symptom of various diseases such as acute bronchitis, chronic bronchitis, pneumonia, tuberculosis, and lung cancer. Most coughs have a limited duration or disappear quickly after treatment, but some patients have persistent cough symptoms. According to the duration of cough, acute cough is within 3 weeks, subacute cough is 3-8 weeks, and cough over 8 weeks is called chronic cough. Chronic cough refers to a history of chronic respiratory diseases without a corresponding chest, physical examination of the chest and chest radiographs, no abnormal findings, that is, the exclusion of organic diseases such as lung cancer, the use of conventional anti-infection or antitussive treatment is invalid. Such patients are most easily neglected by doctors and patients themselves, and the causes of chronic cough are numerous and extensive. Many patients have been misdiagnosed as "chronic bronchitis" or "bronchitis" for a long time. The use of antibacterial drugs is ineffective. It is often difficult to diagnose and repeat various tests, which not only increases the patient's pain, but also increases the patient's financial burden. Affect the patient's daily work and quality of life, increasing the incidence of adverse drug reactions. In addition, frequent coughing can cause a variety of complications.

Cause

Chronic cough involves a variety of causes, not only related to the respiratory system, but also to the nose, throat, and digestive system. The six major causes of chronic cough are: postnasal drip syndrome, cough variant asthma, gastroesophageal reflux, eosinophilic bronchitis, chronic pharyngitis, and psychogenic cough.

Respiratory diseases: When the mucous membranes of the nasopharynx to the small bronchus are stimulated, they can cause cough, such as pharyngitis, tracheal-bronchitis, bronchiectasis, bronchial asthma, allergic substances, and bacterial infections in the lungs.

Pleural disease: pleurisy, pleural mesothelioma, spontaneous pneumothorax, etc., for various reasons.

Cardiovascular disease: mitral stenosis or other causes of left heart failure caused by pulmonary congestion or pulmonary edema.

Central nervous factors: The impulse from the cerebral cortex is transmitted to the medullary cough center, such as encephalitis and meningitis.

an examination

Chronic cough is the most common cough variant asthma. The disease is cough as the only symptom, so the clinical features are lack of specificity, and the rate of misdiagnosis is very high. Therefore, for a chronic recurrent cough should be thought of the possibility of the disease. Since about 50%-80% of children with cough variant asthma develop into typical asthma, about 10-33% of adults with cough variant asthma can develop into typical asthma, and many authors consider cough variant asthma as asthma. Pre-existing performance, therefore early diagnosis and early treatment of cough variant asthma is very important to prevent asthma. Mainly have the following clinical features:

(1) Population: The incidence of children is high. It has been found that more than 30% of children with dry cough are associated with cough variant asthma. In adults, the age of onset of cough variant asthma is higher than that of typical asthma. About 13% of patients are older than 50 years old, and middle-aged women are more common.

(b) Clinical manifestations: Cough may be the only symptom of asthma, mainly long-term intractable dry cough, often induced by inhalation of irritating odor, cold air, exposure to allergens, exercise or upper respiratory tract infection, and some patients have no incentives. More intensified at night or in the early hours of the morning. Some patients have a certain seasonality, with more spring and autumn. Most patients have been treated with cough and expectorant drugs and antibiotics for a period of time, almost no effect, and the use of glucocorticoids, anti-allergic drugs, 2 receptor agonists and theophylline can be alleviated.

(3) History of allergies: Patients themselves may have a clear history of allergic diseases, such as allergic rhinitis and eczema. Some patients can be traced back to a family history of allergies.

(4) Signs: Although it may also have bronchospasm, it often occurs in the tiny bronchi of the distal end or transient paralysis, so the wheezing sound is not heard or rarely heard during the physical examination.

Related checks:

1. Increased airway reactivity, mostly light-moderate increase. The test procedure can induce irritating coughs at similar onset.

2. Pulmonary function damage is between normal people and typical asthma.

3. The skin allergen test can be positive.

4. Increased serum IgE levels.

5. Some patients may be positive for bronchiectasis test. When a positive reaction occurs, it indicates that there is a certain degree of paralysis and obstruction in the airway.

6. Peripheral blood eosinophil counts increased and serum ECP levels increased.

Differential diagnosis

Because cough is a non-specific symptom of many diseases, it is necessary to ask for detailed history, comprehensive physical examination, chest X-ray, electrocardiogram, fiberoptic bronchoscopy and some special examinations to eliminate chronic diseases and intractable cough. Other diseases. Chronic bronchitis, gastroesophageal reflux, bronchial asthma, and posterior nostril drip are the most common causes of chronic cough, and some patients with gastroesophageal reflux can coexist with bronchial asthma. In addition, chronic heart failure, esophageal hiatal hernia, allergic rhinitis, hypertension, airway inflammation, tumors, tuberculosis, foreign body and smoke irritation, anxiety, etc. can lead to chronic cough.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.