Interstitial lung diease (ILD) represents a large group of diffuse diseases caused by different causes that invade the alveoli, alveolar walls, alveolar tracts, fine bronchi and microvasculature and can progress to diffuse interstitial lung fibrosis, which can eventually lead to respiratory failure. Because the lesions invade the alveolar epithelium and the alveolar cavity parenchyma, it is now considered more appropriate to call ILD diffuse parenchymal lung disease (diffuse lung diease , DPLD). Interstitial lung diseases include about 200 different diseases, of which about 1/3 have a clear etiology, but the most influential in clinical diagnosis and treatment are those with an unknown cause, with idiopathic pulmonary fibrosis (IPF) being the most common. Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive interstitial lung lesion of unknown cause. The frequent changes in the international classification of IPF in recent years are indicative of the lack of understanding of the disease. Modern medicine considers it to be an autoimmune disease. The incidence and mortality rate have been increasing in recent years, and its etiology and pathogenesis are unknown to date. The onset of the disease is mostly after 50 years of age, with an insidious onset, manifested by progressive worsening of dyspnea and dry cough during activity, which may be accompanied by general malaise, malaise, fever and weight loss, etc. Small popping sounds at the end of inspiration and pestle-like fingers (toes) can be heard at the base of the lungs. Typical radiographic signs are diffuse reticular or reticulonodular interstitial exudates mainly in the base and outer bands of both lungs, cellular lung and reduced lung volume. Pulmonary function is characterized by reduced lung volume or lung volume, reduced diffusion volume (DLco) or reduced DLco/alveolar ventilation (VA), and hypoxemia, with marked cyanosis, pulmonary hypertension, and right heart insufficiency seen in advanced stages. Clinical manifestations are characterized by mild dry cough, chest tightness, wheezing and progressive dyspnea, and finally death due to respiratory failure. The prognosis of this disease is poor, with survival between 4 and 6 years (5-year survival rate of 30%-50%) in the medium term after the appearance of respiratory distress, and immunosuppressive agents such as glucocorticoids and cyclophosphamide are mainly used, but no satisfactory results have been achieved. There is no record of IPF in the ancient literature of Chinese medicine, and most medical practitioners classify it as “lung impotence”, “lung paralysis”, “lung distension”, ” The disease is caused by the deficiency of positive qi and repeated external sensation, which leads to the paralysis of lung qi. (1) The onset of the disease is mostly in middle age or older, male:female ≈ 2:1, and rare in children. (2) The onset of the disease is insidious, mainly manifested as dry cough and progressive dyspnea, which is obvious after activity. (3) The disease rarely involves extra-pulmonary organs, but systemic symptoms such as fatigue, arthralgia and weight loss may occur. 2, signs (1) about 50% of patients appear pestle fingers (toe), most patients can hear velcro sounds in the lower part of both lungs. (2) Cyanosis appears in the late stage, and occasionally pulmonary hypertension, pulmonary heart disease and right heart insufficiency may occur. (2) Physical and chemical examination (1) X-ray chest film (high kV) (1) often shows reticular or reticular nodular shadow with lung volume reduction. As the disease progresses, multiple cystic transillumination shadows (honeycomb lung) with a diameter of 3 to 15 mm may appear. (2) Lesion distribution: Mostly bilateral diffuse, relatively symmetrical, unilateral distribution is rare. The lesions are mostly distributed in the basal, peripheral or subpleural areas. (3) In a few patients with symptoms, there may be no abnormal changes on X-ray chest film. 2.HRCT （1）HRCT scan can help to evaluate the abnormal changes in the peripheral part of the lung, diaphragm, mediastinum and around the bronchovascular bundle, which is of great value for the diagnosis of IPF. (2) Sublobular microstructural changes, such as linear, reticular, and ground glass shadows, can be seen. (3) The lesions are usually seen in the peripheral part of the middle and lower lung fields, often appearing as reticular and foveal lung, but also crescentic shadows, subpleural linear shadows and very few ground glass shadows. In most patients, a combination of these images is present. In areas of severe fibrosis, there is often traction bronchial and fine bronchial dilatation and/or subpleural cellulite-like changes. Pulmonary function tests (1) Typical pulmonary function changes are restrictive ventilatory dysfunction, manifested as a decrease in total lung capacity (TLC), functional residual volume (FRC) and residual volume (RV). Expiratory volume per second/exertional lung volume (FEV1/FVC) is normal or increased. (2) Single breath diffusion of carbon monoxide (DLCO) is reduced, i.e., DLCO may be reduced even when ventilation and lung volume are normal. (3) Ventilation/blood flow ratio is imbalanced, PaO2 and PaCO2 are decreased, and the partial pressure difference of alveolar arterial oxygen [P(A a)O2] is increased. 4, BALF test (1) The significance of the BALF test is to narrow the diagnosis of ILD, i.e., to exclude other lung diseases (such as tumor, infection, eosinophilic pneumonia, exogenous allergic alveolitis, nodular disease and alveolar protein deposition). However, it is of limited value in diagnosing IPF. (2) The number of neutrophils (PMN) in the BALF of patients with IPF increases, accounting for more than 5% of the total number of cells, and some patients in advanced stages also have an increase in eosinophils. 5.Blood test (1) The blood test results of IPF lack specificity. (2) Increased erythrocyte sedimentation rate, increased levels of gammaglobulin and lactate dehydrogenase (LDH) can be seen. (3) Some antibodies are positive or the titer is increased, such as anti-nuclear antibody (ANA) and rheumatoid factor (RF) may be weakly positive. 6. Histopathological changes (1) Histopathology of open/thoracoscopic lung biopsy shows UIP changes. (2) The lesions are unevenly distributed, with the lower lungs being the most affected, and fibrosis around the subpleural and peripheral lobular septa is common. (3) Under low magnification microscopy, the lesions were characterized as “light and heavy, old and new”, i.e. the lesions were not uniform in phase, and the extensive fibrosis and cellular lung tissue were often mixed with early lesions or normal lung tissue such as inflammatory cell infiltration and alveolar septal thickening. (4) The lung fibrosis area is mainly composed of dense collagenous tissue and proliferating fibroblasts. Focal proliferation of fibroblasts constitutes the so-called “fibroblast foci”. The cellular lung is partially composed of cystic fibrous air spaces, often lined with fine bronchial epithelium. In addition, smooth muscle cell hyperplasia is seen in the fibrotic and cellular lung areas. (5) Diagnostic criteria to exclude other known causes of ILD and other types of IIP (iii) Diagnostic criteria1 In 2002, the Chinese Society of Respiratory Medicine proposed diagnostic criteria for IPF: The diagnostic criteria for IPF can be divided into those with surgical (open chest/thoracoscopic) lung biopsy data and those without surgical lung biopsy data. I. With surgical lung biopsy data 1. Pulmonary histopathological manifestations characteristic of UIP. 2, except for other known causes of interstitial lung disease, such as drugs, environmental factors and rheumatic diseases caused by pulmonary fibrosis. 3, Pulmonary function abnormalities, manifested as restrictive ventilation dysfunction and/or impaired gas exchange. 4. Typical abnormal images can be seen on chest radiograph and HRCT. Second, no surgical lung biopsy data (clinical diagnosis) The lack of lung biopsy data in principle can not confirm the diagnosis of IPF, but if the patient has normal immune function and meets all of the following primary diagnostic conditions and at least 3/4 of the secondary diagnostic conditions, the clinical diagnosis of IPF can be made. 1, the primary diagnostic conditions: (1) except for known causes of ILD, such as the toxic effects of certain drugs, occupational environmental exposure history and rheumatic diseases, etc.. (2) abnormal pulmonary function, including restrictive ventilation dysfunction (reduced VC with normal or increased FEV1/FVC) and/or impaired gas exchange [increased P(A a)O2 or decreased DLCO at rest/exercise]; (3) chest HRCT showing reticular changes in both lungs, with advanced honeycomb lung, which may be accompanied by a minimal amount of ground glass shadow; (4) transbronchial lung biopsy ( TBLB) or BALF examination does not support the diagnosis of other diseases. Secondary diagnostic criteria: (1) age >50 years; (2) insidious onset or progressive dyspnea without a clear cause; (3) duration of disease ≥3 months; (4) inspiratory velcro sounds can be heard on auscultation of both lungs. The name of the disease is found in the Huangdi Neijing, which states that if the skin paralysis does not heal, the lung paralysis is caused by the repeated exposure to evil spirits. It is believed that if a paralysis of the skin does not heal, it is repeatedly caused by evil spirits and is internally surrendered to the lungs. “Those with lung paralysis are annoyed and full, panting and vomiting.” “Pornographic gas and wheezing, paralysis gathered in the lungs.” Chinese medicine believes that lung paralysis is caused by deficiency and insufficiency, such as “Su Wen? The five viscera generation chapter: “wheezing and deficiency, called lung paralysis, cold and heat, get drunk and make the internal also.” Su Wen? The Four Times of Inversions: “The skin paralysis is not finished, and in case of evil, it moves into the lungs.” Warm poison, epidemic poison, and the six excessive transformation into poison or the internal invasion of external evil into poison, etc.; it is the function of the internal organs and the operation of Qi and blood malfunction so that the physiological or pathological products in the body can not be discharged in a timely manner, and accumulate too much in the body and become born. Generally speaking, external poisonous evil, enter the blood, depleting the Ying yin, luo injury and blood addiction, luo qi paralysis, qi stagnation, lifting and lowering the in and out of the division, wheezing, coughing frequently; internal poison often occurs on the basis of internal injuries, mostly from the accumulation of all the evil, gumming and stagnation. Phlegm and stagnation, paralysis and obstruction of the veins. It is often aggravated by the accumulation of phlegm and stagnation, paralyzing the ligaments and veins. It is a vicious circle, which makes the lung ligaments and veins lingering and prolonged and gradually become chronic diseases. It can be seen that the lung complex lesion can be caused by external poisonous evil (secondary). It can also be caused or aggravated by internal toxins (idiopathic), because they are all caused by toxins damaging the lung ligaments and blocking the ligaments, which can eventually lead to the pathological end of deficiency, phlegm, stasis, and interconnection of toxins and paralysis of the ligaments or deficiency of the ligaments. Lung impotence, first described in Zhang Zhongjing’s Jin Kui Yao, is a disease caused by the weakness of lung qi and its inability to distribute qi and fluid, with coughing and salivation as the main symptoms. Interstitial lung fibrosis is called “lung paralysis” mainly for the following reasons:① In terms of morphology, the volume of both lungs shrinks in the middle and late stages of lung fibrosis, and the total volume of lung, residual air volume and tidal volume are significantly reduced, which is consistent with the original meaning of “lung impotence”. The basic pathological characteristics of pulmonary gangrene are lung heat and leaf anxiety, deficiency of fluid and blood, and loss of moistening. Lung fibrosis is persistent, and the pathogenesis transforms from Qi to Blood, from Lung to Kidney, with deficiency of both Lung and Kidney, and deficiency of Qi and Blood, with deficiency of the liao not being honored, “deficiency of the liao leads to impotence”. The deficiency of the liao is impotent, which fully illustrates the characteristics and evolution of the pathogenesis of liao deficiency and dishonor of lung impotence. In summary, both “pulmonary paralysis” and “pulmonary impotence” can be used as the TCM diagnosis of pulmonary interstitial fibrosis. Both of them reflect the characteristics of the pathogenesis of pulmonary fibrosis at different stages of its development, but pulmonary paralysis and pulmonary impotence can affect each other under certain conditions and become diseases. Generally speaking, there is a clinical evolution of pulmonary fibrosis from pulmonary paralysis to pulmonary impotence, i.e., deficiency due to actuality. However, “the place where deficiency exists is the place where evil is retained”, and pulmonary impotence is commonly associated with paralysis of the lung channels, i.e., deficiency leads to actuality. The early stage of the disease is similar to pulmonary paralysis, and the later stage is similar to pulmonary impotence. In the early stage, paralysis by wind, dampness, phlegm and heat is the main cause, while in the later stage, lung, spleen and kidney deficiency is the main cause, and the disease changes from real to deficient, but the blockage of qi and blood is present throughout the disease. In short, pulmonary fibrosis can often be seen as a complex pathology of impotence within paralysis (deficiency due to actuality) and paralysis within impotence (actuality due to deficiency). (1) Yin deficiency and lung dryness symptoms: chest tightness and shortness of breath, aggravated by movement, dry cough without sputum or little sputum, not easily coughing up, coughing violently, occasionally blood in sputum, coughing with chest pain, dry throat and dry mouth, dry mouth and thirst. The tongue is red and less fluid, with little or thin yellow coating, and the pulse is thin and tense. Treatment: Benefit Qi, nourish Yin, clear lung and moisten dryness. Remedy: Clearing dryness and saving lung with addition and subtraction. Drugs: Radix Codonopsis pilosulae 30g, Radix gypsum 30g, Radix mulberry leaf 10g, Radix maitake 15, Radix et Rhizoma Polygonati 30g, Radix almonds 10g, Radix loquatulae 10g, Radix penicillatae 10g, Radix et Rhizoma sea clam shell 15g, Radix et Rhizoma gum 10g, Radix glycyrrhizae 10g. (2) Pulmonary complex paralysis, Qi-Yin deficiency Symptoms: shortness of breath, shortness of breath when moving, shortness of breath, dry cough without sputum or little sputum, fatigue, chest tightness, chest pain, dry mouth and throat, night sweating, spontaneous sweating The symptoms include: irritable heat in the five hearts, lumbar soreness and knee weakness, pale or blue nails in the mouth and lips, dull skin without luster, pestle-like fingers (toes). Tongue and pulse: dark red or reddish-red tongue, little moss or white moss, sunken and fine pulse or fine and weak pulse. Treatment: Drain the lung channels, soften hardness and disperse blood stasis, benefit Qi and nourish Yin. Radicals: Lung Fibrillation Formula with addition and subtraction. Radix et Rhizoma Polygonatum 15g, Radix ethiopogonis 15g, Radix ethiopogonis 10g, Radix ethiopogonis 12g, Radix trigonis 10g, Radix curculigo 10g, Radix Astragali 30g, Radix ethiopogonis 30g, Radix glycyrrhiza 6g, etc. (3) Deficiency of liver and kidney, Qi deficiency and blood stasis Symptoms: chest tightness and distension, shortage of breath, aggravated by movement, dry cough with little phlegm, dry mouth and throat, palpitation and weakness, swelling of limbs, purple lips and nails, dizziness, dark red tongue with white or white greasy coating, sunken and thin pulse. Treatment: Tonifying the liver and kidney, benefiting the Qi and activating the blood Cure: Liu Wei Di Huang Wan with reduction. Dihuang 30g, Cornu Cervi Pantotrichum 15g, Yam 15g, Dampi 12g, Poria 12g, Trigonella 10g, Curcuma 10g, Radix Codonopsis 30g, Rhodiola 10 g (4) Phlegm-Heat Closure of Lung Symptoms: Chest tightness and shortness of breath, increased by movement, shortness of breath, cough, coughing, coughing and vomiting of sticky phlegm, not easy to cough, chest tightness, occasional chest pain, heartburn, dry and bitter mouth, constipation, dark red nails of the mouth and lips, dull skin without luster, pestle-like fingers (toes). Pestle-like fingers (toes). The tongue is dark red with white or yellowish greasy coating, and the pulse is smooth or slippery. Treatment: Clearing phlegm and clearing lung, activating blood circulation. Remedy: Warming gall bladder soup with reduction. Semen 10g, Poria 15g, Chen Pi 10g, Citrus aurantium 10g, Lonicera japonica 30g, Peach kernel 10g, Astragalus membranaceus 30g, Haifu Shi 15g, Glycyrrhiza glabra 6g, etc. Western medicine treatment】 1 Recommended drugs and doses The recommended treatment plan is: glucocorticoids combined with cyclophosphamide or azathioprine, as follows (for reference). (1) Glucocorticoids: Prednisone or other equivalent doses of glucocorticoids, 0.5 mg/kg per day (ideal body weight, same as below) orally for 4 weeks; then 0.25 mg/kg per day orally for 8 weeks; then reduce the dose to 0.125 mg/kg per day or 0.25 mg/kg orally once every other day. (2) Cyclophosphamide: administered at 2mg/kg per day. The starting dose can be 25-50mg/day orally, increasing by 25mg every 7-14 days until the maximum amount of 150mg/d. (3) Azathioprine: administered at 2-3mg/kg/day. The initial dose is 25-50mg/d, and then the dose is increased by 25mg every 7-14 days until the maximum amount of 150mg/d. 2 Course of treatment and determination of efficacy (1) Course of treatment: ①General observation of efficacy after 3 months of treatment, if the patient tolerates well and no complications or side effects occur, the treatment can be continued for at least 6 months or more. If the patient has been treated for more than 6 months, if the condition deteriorates, the treatment should be stopped or changed or combined with other drugs; if the condition is stable or improving, the original treatment should be maintained. Generally, the combination of drugs is advocated. If the condition of the patient has been treated for more than 12 months, the treatment should be stopped or changed or combined with other drugs if the condition deteriorates; if the condition is stable or improving, the original treatment should be maintained. (4) For patients who have been treated for more than 18 months, the continuation of treatment should be individualized. (2) Judgment of efficacy: good response or improvement: ①Reduced symptoms and increased mobility. ②Reduction of abnormal images on X-ray chest film or HRCT. ③Pulmonary function performance TLC, VC, DLCO and PaO2 remain stable for a longer period of time. The following data are for reference: TLC or VC increased ≥10%, or at least increased ≥200ml; DLCO increased ≥15% or at least increased 3ml?min 1?mmHg 1; SaO2 increased >4%; PaO2 increased ≥4mmHg in cardiopulmonary exercise test (those with 2 or more items are considered to have improved pulmonary physiological function). Poor response or treatment failure: ① worsening of symptoms, especially dyspnea and cough. (ii) Increased abnormal images on X-ray chest film or HRCT, especially with signs of cellular lung or pulmonary hypertension. ③Worsening lung function. The following data are for reference: ≥10% decrease or ≥200ml decrease in TLC or VC; ≥15% decrease or at least ≥3ml?min 1?mmHg-1 decrease in DLCO; ≥4% decrease in SaO2 or ≥4mmHg increase in P(A-a)O2 on exercise test (those with 2 or more items are considered to have worsened pulmonary function).