(1) Acute cough and chronic cough

　　From the perspective of diagnosis, we artificially divide cough into three categories: acute cough, subacute cough and chronic cough . Acute cough time is shorter than 3 weeks, subacute cough 3-8 weeks, chronic cough ≥ 8 weeks. (Note: The definition of chronic cough in children is different from that in adults, chronic cough is ≥ 4 weeks)

　　 1. Acute cough: It is the most common respiratory symptom in clinic, and the common cold is the most common cause of acute cough. Other causes include acute bronchitis, acute sinusitis, allergic rhinitis, acute exacerbation of chronic bronchitis, and bronchial asthma (referred to as asthma).

　　 2. Subacute cough: The most common causes are cough after cold (also called cough after infection), bacterial sinusitis, asthma, etc.

　　3. Chronic cough: There are many causes of chronic cough in adults, which can usually be divided into two categories: one is those who have clear lesions on the first examination of X-ray chest radiographs, such as pneumonia, tuberculosis, lung cancer, etc.; Class X-ray chest radiographs have no obvious abnormalities, and those with predominantly cough as the only symptom are commonly known as chronic coughs of unknown origin (referred to as chronic cough). Common causes of chronic cough are: cough variant asthma (CVA), retronasal drip syndrome (PNDs), eosinophilic bronchitis (E), and gastro-esophageal reflux cough (GERC). These causes account for The proportion of chronic cough in the respiratory medicine clinic was 70％～95％. Other etiologies are rare, but involve a wide range, such as chronic bronchitis, bronchiectasis, endometrial tuberculosis, allergic cough (AC), psychological cough, etc.

　　(2) Chronic cough in children

　　The causes of chronic cough in children are different from adults, and the causes of chronic cough in children of different ages are also different, so The diagnosis and treatment of children''s cough cannot completely follow the adult guidelines, but there should be a diagnosis and treatment guide for chronic cough that meets the characteristics of children.

　　 The causes of chronic cough are divided into specific cough and non-specific cough. Among them, non-specific cough means that cough is the main or only manifestation, and no abnormal chronic cough is found on chest X-ray. At present, clinical chronic cough mainly refers to this type of cough, also known as "narrow cough". The causes of nonspecific cough in children are age-specific and require careful systematic evaluation, detailed medical history and physical examination. Chest x-rays are required for these children. Pulmonary ventilation should be performed for those of appropriate age.

　　(3) Dry cough and wet cough

　　Dry cough refers to a cough with no or less secretions. Common diseases include acute laryngitis or upper respiratory tract Acute cough during infection. A sputum cough is a wet cough, often referring to a daily sputum volume above 30 ml. Common diseases are acute or chronic bronchopneumonia. Generally speaking, cough with sputum is common in bronchopulmonary diseases, so excessive mucus will be generated and move up to the throat to cause cough and sputum discharge. However, cough with sputum can also be regenerated from upper airway cough syndrome (also called retronasal drip syndrome), which means that the secretion comes from the upper airway. Distinguishing whether cough has phlegm can help the diagnosis of the disease and the choice of antitussive drugs.

　　Talk to you about chronic cough in children

　　In the clinic, I often see some children who come to the clinic because of a long-term cough. These children have a common thing, coughing repeatedly, taking medicine better, stopping the medicine and then sending it, parents always feel that they can''t go to the "root", go to the hospital, and have done a lot of checks, or even non-stop infusion, but the child still coughs, this What the hell is going on?

　　What is chronic cough?

　　For children, cough symptoms last more than a month before they can be called chronic cough. There are two types of chronic cough. One is specific cough, which means that the diagnosis of the disease is very clear. For example, the child has bronchial pneumonia and there are problems on the chest radiograph. Cough is one of the symptoms of this disease. This cough is called specific cough. There is also a non-specific cough, which means that the cause of the cough is temporarily unclear. The cough is the main or only manifestation. There is no abnormality on the chest X-ray. The cough is more than a month. At present, clinical chronic cough mainly refers to this type of cough, also known as

　　 "chronic cough in a narrow sense". What I introduce to you today is this "chronic cough". There are many causes of chronic cough in children. After more than a year of observation, I conducted a three-month follow-up and guided medication for more than 100 children with chronic cough in our hospital. I have a deeper understanding of chronic cough in children.

　　The survey made me understand that the causes of chronic cough in children are different from those in adults, and the causes of chronic cough in children of different ages are also different.

　　Infants younger than 1 year old, the common causes of chronic cough are: respiratory tract infection and cough after infection, congenital trachea, lung dysplasia, gastroesophageal reflux, tuberculosis, etc.; children 1 to 3 years old, Common causes are: respiratory tract infection and cough after infection, upper airway cough syndrome, cough variant asthma, airway foreign body, gastroesophageal reflux, tuberculosis, etc.; preschool children from 3 to 6 years old, the same as early childhood The etiology, in addition, there are diseases such as bronchiectasis; in addition to the above-mentioned diseases, school-age children after 6 years of age also have psychogenic cough.

　　Here are some brief introductions to the common causes described above:

　　1. Respiratory tract infection and cough after infection:

　　 Many pathogenic microorganisms such as Pertussis, Mycobacterium tuberculosis, viruses (especially respiratory syncytial virus, parainfluenza virus, cytomegalovirus), mycoplasma pneumoniae, chlamydia and other respiratory tract infections are common causes of chronic cough in children, more common in 4 weeks, often at night and/or early morning, coughing after exercise and cold air, no clinical signs of infection or antibiotic treatment ineffective for a long time;

　　(2) Bronchodilator diagnosis Sexual therapy can significantly relieve the symptoms of cough;

　　(3) Normal lung ventilation function, bronchial provocation test suggests high airway responsiveness;

　　(4) History of allergic diseases including A history of drug allergies and a positive family history of allergic diseases. A positive allergen test can aid diagnosis;

　　(5) except for chronic cough caused by other diseases.

　　3. Upper Airway Cough Syndrome (UACS):

　　Various rhinitis (allergic and non-allergic), sinusitis, chronic pharyngitis , Chronic tonsillitis, nasal polyps, adenoid hypertrophy, and other upper airway diseases can cause chronic cough. Previously diagnosed as post-nasal drip (flow) syndrome (PNDs), which means that nasal secretions flow back to the pharynx through the posterior nostril Cough caused.

　　UACS clinical features and diagnostic clues:

　　(1) Chronic cough with or without sputum, coughing is usually in the early morning or when the posture changes, often accompanied by nasal congestion, flow Stomach, dry pharynx with foreign body sensation, repeated pharyngeal swelling, sensation of mucus attachment in the posterior pharyngeal wall, a small number of children complained of headache, dizziness, low fever, etc.;

　　(2) Check that there may be tenderness in the sinus area, There may be yellow-white secretions flowing out of the opening of the sinuses, and the follicles of the posterior pharyngeal wall are obviously proliferated, and they are cobblestone-like, and sometimes the fluid samples of the posterior pharyngeal wall are attached;

　　(3) Targeted treatment such as Antihistamines and leukotriene receptor antagonists, nasal glucocorticoids, etc. are effective;

　　(4) For sinusitis, the sinus sinus radiographs or CT films can be seen to change accordingly.

　　4. Gastroesophageal reflux cough (GERC):

　　Gastroesophageal reflux (GER) is a physiological phenomenon in infants and young children. The incidence of GER in healthy infants is 40％65％, reaching a peak in 1-4 months, and more naturally relieved at 1 year old. When it causes symptoms and/or is accompanied by gastroesophageal dysfunction, it becomes a disease, or gastroesophageal reflux disease (GERD). The prevalence of GER in children is about 15％.

　　GERC''s clinical features and diagnostic clues:

　　(1) paroxysmal cough, sometimes severe cough, mostly at night;

　　(2) symptoms Most of them appear to be difficult to feed after diet. Some children have discomfort in the upper abdomen or under the xiphoid process, a burning sensation behind the breastbone, chest pain, sore throat, etc.;

　　(3) In addition to causing cough, infants can also cause suffocation, bradycardia and back appearance Bow;

　　(4) can cause the child''s growth and development to be stagnant or delayed.

　　5. Eosinophilic bronchitis (EB):

　　The disease was first reported by Gibson et al in 1989, and the clinical features are Chronic cough, no wheezing, no wheezing in both lungs, normal lung function, peak flow rate variability, and airway responsiveness, but the proportion of eosinophils in induced sputum is >3％, usually 10％～ Between 15％ antibacterial drugs and bronchodilator drugs can not relieve cough, only respond to glucocorticoids, while the symptoms of cough are controlled, eosinophils in induced sputum are also reduced. At present, my country has not seen large sample research surveys.

　　EB clinical features and diagnostic clues:

　　(1) chronic irritant cough;

　　(2) chest X-ray film is normal;

　　(3) Normal lung ventilation and no airway hyperresponsiveness;

　　(4) Relative percentage of eosinophils in sputum>3％;

(5) Oral or inhaled human glucocorticoid therapy is effective.

　　6. Congenital respiratory diseases:

　　 is mainly found in infants and young children, especially within 1 year of age. Including congenital tracheoesophageal fistula, congenital vascular malformation compresses the airway, laryngotracheal bronchial softening and/or stenosis, bronchopulmonary cyst, ciliary dyskinesia, mediastinal tumor, etc.

　　7. Psychogenic cough:

　　Childhood psychogenic cough can only be excluded except for tic disease and cough after behavior intervention or psychotherapy Diagnosis can only be made after improvement; the cough characteristics are only indicative of psychogenic cough, but not diagnostic.

　　Clinical features and diagnostic clues of psychogenic cough:

　　(1) more common in older children;

　　(2) daytime cough is the main, Focus on something or cough disappears during night rest;

　　(3) is often accompanied by anxiety symptoms;

　　(4) is not accompanied by organic diseases, except for causing chronic Other causes of coughing.

　　8. Other causes:

　　 (1) Foreign body inhalation: Coughing is the most common symptom after foreign body inhalation in the airway, and foreign body inhalation is in children Especially an important cause of chronic cough in children 1 to 3 years old. The study found that 70% of patients with airway foreign body inhalation showed cough, and other symptoms still include decreased breath sounds, wheezing, and history of asphyxia. Cough is usually manifested as paroxysmal severe choking, or only chronic cough with obstructive emphysema or atelectasis. Once the foreign body enters the part below the small bronchus, there is no cough, which is called the "silent area". .

　　(2) Drug-induced cough:

　　Children rarely use angiotensin-converting enzyme inhibitors (ACEI), and some children with renal hypertension use ACEI such as Cato Puli can cause coughing. The mechanism may be related to the secretion of bradykinin, prostaglandins, and substance P. The cough caused by ACEI usually manifests as chronic persistent dry cough, which worsens at night or in the lying position. Stopping the medicine for 3 to 7 days can significantly reduce or even disappear the cough.

　　(3 ) Otogenic cough: 2％-4％ people have vagus ear branches. In this part of the population, when a disease occurs in the middle ear, the vagus nerve is stimulated to cause a chronic cough. Otogenic cough is a rare cause of chronic cough in children.