diagnosis

　　Ask detailed medical history (including the triggers of the disease, the number of attacks, the duration of each attack, the time pattern and seasonality of the attacks, previous treatment measures and response to treatment, etc.) to understand the allergic history of yourself and your family, and combine the child's breathing during the attack with Diagnosis of gastric dyspnea is not difficult if the expiratory phase is prolonged during lung auscultation and wheezes are heard in the expiratory phase. Pulmonary ventilation function tests, airway reactivity measurements or bronchiectasis tests are helpful in the diagnosis and severity of asthma. Judgment, but it is difficult for young children to cooperate, so it is subject to certain restrictions. In addition, skin allergen testing can also assist in diagnosis.

　　1. Diagnostic criteria for childhood asthma

　　(1) Diagnostic criteria for asthma in infants and young children: ① Age <3 years old, asthma attacks ≥3 times. ②During the attack, wheezing in the expiratory phase is heard in both lungs, and the expiratory phase is prolonged. ③Have atopic constitution, such as allergic eczema, allergic rhinitis, etc. ④Parents have a history of allergies such as asthma. ⑤Exclude other diseases that cause wheezing.

　　Asthma can be diagnosed if the above items ①, ②, and ⑤ are present. If wheezing occurs twice and items ② and ⑤ are present, the diagnosis is suspected asthma or wheezing bronchitis. If items ③ and/or ④ are present at the same time, asthma can be diagnosed. In this case, a therapeutic diagnosis of asthma may be considered.

　　(2) Diagnostic criteria for asthma in children: ① Age ≥ 3 years old, wheezing occurs repeatedly (or it may be traced to some allergen or irritating factor). ② During the attack, stridor sounds mainly in the expiratory phase are heard in both lungs, and the expiratory phase is prolonged. ③ Bronchodilators have obvious effects. ④Exclude other diseases that cause wheezing, chest tightness and cough.

　　For those with suspected asthma and wheezing in the lungs in each age group, any of the following bronchodilation tests can be performed: ① Inhalation of aerosol or solution of β2 receptor agonist (refer to the above bronchodilation test for dosage and method) ); ②1‰Epinephrine is injected subcutaneously at 0.01ml/kg, with the maximum dose not exceeding 0.3ml each time. 15 minutes after any of the above tests, if the wheezing is significantly relieved and the wheezing in the lungs is significantly reduced, or the FEV1 is improved ≥15 %, the bronchiectasis test is positive and can be used to diagnose asthma.

　　(3) Diagnostic criteria for cough variant asthma (CVA): ① Cough that lasts or recurs for >1 month, often attacks at night and/or early in the morning, with less phlegm, and is related to smelling irritating odors, climate changes, exercise, etc. . ② There are no clinical signs of infection, or long-term antibiotic treatment is ineffective. ③ If you have a personal or family history of allergies, a positive allergen skin test can assist in the diagnosis. ④ There is airway hyperresponsiveness (positive bronchial provocation test), positive bronchiectasis test or PEF daily variation rate or weekly variation rate ≥ 15%. ⑤ Treatment with bronchodilators and/or glucocorticoids can relieve cough attacks (basic diagnostic condition).

　　2. Staging and severity grading of asthma Staging of asthma: The course of asthma can be divided into acute attack phase and remission phase. An acute attack of asthma refers to the sudden onset or worsening of shortness of breath, cough, chest tightness and other symptoms, and often dyspnea and wheezing. , accompanied by reduced expiratory flow, the remission period refers to the disappearance of symptoms and signs after treatment or without treatment, and the lung function returns to the level before the acute attack, and maintains it for more than 4 weeks.

　　Evaluation of asthma conditions: The evaluation of asthma patients should be divided into 2 parts:

　　(1) Overall evaluation of the condition in the non-acute attack period: Many asthma patients always experience symptoms (wheezing, coughing, chest tightness) with varying frequency and/or varying degrees for a long period of time even if they do not have an acute attack at the time of treatment. , so it is necessary to make a general evaluation of the condition based on the frequency and severity of attacks some time before treatment, as well as medications and lung function.

　　When the patient is already in the standardized grading treatment period, the asthma severity grading should be comprehensively judged based on the current clinical manifestations and the current level of the daily treatment plan. This grading method reflects the response of the asthma patient to the adopted treatment plan, that is, it reflects Understand the condition of the disease control, so that the selected treatment plan can be adjusted (upgraded or downgraded) in a timely manner.

　　(2) Evaluation of the severity of acute asthma attacks: Correct assessment of the severity of acute asthma attacks is the basis for timely and effective treatment. Understanding severe asthma is the key to avoiding deaths caused by asthma.

　　Differential diagnosis

　　Since the clinical manifestations of asthma are not specific to asthma, wheezing, chest tightness and cough caused by other diseases need to be excluded while establishing the diagnosis.

　　1. Cardiogenic asthma: Cardiogenic asthma is common in left heart failure. The symptoms during an attack are similar to those of asthma. However, cardiogenic asthma often has medical history and signs of rheumatic heart disease and congenital heart disease, such as paroxysmal coughing, Pink frothy sputum is often coughed up, extensive vesicular sounds and wheezing can be heard in both lungs, the left heart boundary is enlarged, the heart rate is increased, and a galloping rhythm can be heard at the apex of the heart. During chest X-ray examination, it can be seen that the heart is enlarged and the lungs are Congestion sign, cardiac B-ultrasound and cardiac function test are helpful for identification. If it is difficult to identify for a while, you can inhale selective β2 receptor agonists by atomization or inject low-dose aminophylline to relieve symptoms and conduct further examination. Do not use epinephrine or morphine. To avoid danger.

　　2. Pulmonary tuberculosis: It can manifest as repeated coughing, sputum production, shortness of breath, etc. For example, airway endothelial tuberculosis can cause obvious asthma, which needs to be differentiated from bronchial asthma. The main identification points are: history of TB exposure; symptoms of chronic TB poisoning; PPD test Positive; negative bronchial provocation test or PEF mutation rate <15%; acid-fast bacilli found in sputum smear, positive sputum TB-PCR, chest X-ray, chest CT examination, and bronchoscopy if necessary to confirm the diagnosis.

　　3. Bronchiolitis: It is mostly caused by respiratory syncytial virus. It is more common in infants and young children under 3 years old, especially under 6 months old. There has been no history of recurring attacks in the past. This time, the onset was acute, with symptoms of upper respiratory tract infection first, and gradually wheezing. , expiratory dyspnea, main signs: prolonged expiration, expiratory stridor and fine crackles, chest X-ray: diffuse emphysema and patchy shadows, inhaled β2 receptor agonists and systemic corticosteroids The efficacy is uncertain, and viral pathogenic testing can confirm the diagnosis.

　　4. Mycoplasma pneumoniae pneumonia: Pulmonary inflammation caused by Mycoplasma pneumoniae. The main clinical manifestation is an irritating dry cough. Generally, there is no obvious difficulty in breathing. The symptoms can last for 2 to 3 months. It is mainly distinguished from CVA. The main identification point is: no recurrence in the past. History of cough and asthma. This time, symptoms of respiratory tract infection such as nasal congestion, runny nose, fever, and cough often start, and then the cough persists and does not heal. Patchy or cloudy shadows can be seen on the chest X-ray, which may be migratory. Cold agglutination test ≥1/64 positive or Mycoplasma pneumoniae antibody positive, macrolide antibiotic treatment is effective.

　　5. Foreign bodies in the airway: There is no history of repeated coughing and wheezing in the past. Before this onset, there was often a history of coughing or clear foreign body inhalation during eating. Physical examination often showed asymmetric breath sounds, weakened breath sounds on the affected side, weakened tactile fremitus and localized Signs such as wheezing, chest X-ray, and chest CT can assist in the diagnosis. Bronchoscopy can confirm the diagnosis and perform foreign body removal at the same time.

　　6. Gastroesophageal reflux (GOR): GOR is caused by the reflux of gastric contents into the esophagus, which stimulates the receptors at the lower end of the esophagus, causing paroxysmal or persistent cough. GOR can be the only or main cause of chronic cough. Patients may have Reflux symptoms include heartburn, upper abdominal fullness, etc., but 75% of patients may not have typical reflux symptoms and only present with chronic cough, negative bronchial provocation test or PEF variation rate <15%, and the anti-asthma treatment effect is poor. 24-hour esophageal pH monitoring showed that the Demeester score of the esophageal electrode was ≥14.72, and the symptom associated probability of reflux and cough was ≥95%. Effective anti-reflux treatment can help the diagnosis.

　　7. Postnasal drip syndrome (PNDs) can manifest as paroxysmal or persistent cough. It is one of the common causes of chronic cough and should be distinguished from CVA. PNDs often have a history of rhinitis and sinusitis, postnasal drip and (or) A feeling of mucus adhesion to the posterior pharyngeal wall. Examination reveals that there is mucus adhesion to the posterior pharyngeal wall, with a cobblestone-like appearance. In patients with sinusitis, sinus films or sinus CT can show that the sinus mucosa is thickened >6 mm or the sinus cavities are blurred or have fluid levels. Cough symptoms are relieved after treatment (such as nasal inhaled corticosteroids, nasal vasoconstrictors, and antibiotics for sinusitis).

　　8. Eosinophilic bronchitis (EB): It is not yet clear whether EB is a separate disease or an early manifestation of asthma. Its main clinical manifestations are chronic cough, no special findings on chest X-ray, and normal pulmonary ventilation function test. The bronchial provocation test is negative, the PEF mutation rate is normal, and the eosinophils in induced sputum are >3%. Effective oral or inhaled corticosteroid treatment can aid the diagnosis.

　　9. Allergic alveolitis is a pulmonary granulomatous inflammatory disease caused by inhalation of organic dust and other allergens. It can be manifested by recurrent coughs, dyspnea, etc. Chest X-ray examination is non-specific and mainly manifests as bilateral symptoms. Infiltrative changes in the lower lungs, decreased pulmonary diffusing function, negative bronchial provocation test or relaxation test, normal PEF mutation rate, no increase in eosinophils and IgE, history of special environment or occupational exposure, and positive allergen-specific antibodies in the serum Can aid diagnosis.

　　10. Diffuse bronchiolitis: It is a diffuse disease that mainly affects the respiratory bronchioles. It can be caused by inhalation injury (toxic gas, smoke, mineral particles, etc.), infection, drugs, etc. Some patients are idiopathic. It is clinically characterized by cough, sputum, wheezing, and shortness of breath. Symptoms are often persistent, widespread wheezing and crepitus in both lungs, negative bronchiectasis test or PEF variation rate <15%, and the antiasthmatic treatment effect is uncertain.

　　11. Hysteria (hysteria): It is a functional disease caused by temporary dysfunction of the cerebral cortex. It often has a "hysterical" character (strong and changeable emotions, self-centeredness, strong desire for expression, rich imagination, and often exaggerated words and deeds). Dramatic), more common in women, with diverse clinical manifestations, including mental and/or physical symptoms, sudden and sudden onset, which can be manifested as episodic "shortness of breath" or "asthma", which often occurs after mental stimulation. Family members Excessive concern or excessive stress can induce or aggravate symptoms. There are no abnormal signs in the lungs during the attack, no abnormality in chest X-ray and other examinations, the bronchial provocation test is negative or the PEF variation rate is <15%, and it can be relieved by suggestive treatment.

　　12. Bronchiectasis: When there is secondary infection, the secretions at the dilated bronchi increase and become blocked, and asthma-like dyspnea and wheezing may occur. Generally, it can be based on previous severe lung infection, repeated atelectasis and coughing. The history of a large amount of pus and sputum can be identified. If necessary, chest X-ray and bronchography or CT examination can make the diagnosis.