Modern medicine still has many unanswered questions about the pathogenesis and progression mechanism of IgA nephropathy, and still lacks specific treatment methods. In contrast, Chinese medicine and combined Chinese and Western medicine have accumulated rich experience in long-term clinical practice in the treatment of IgA nephropathy. Therefore, TCM evidence-based treatment is still an important part of IgA nephropathy treatment. 1, etiology and pathogenesis There is no specific discussion on IgA nephropathy in Chinese medicine, but according to its clinical manifestations, it is considered to be related to “blood in urine”, “back pain”, “deficiency labor”, “kidney wind”, “kidney disease” and “kidney disease”. However, according to its clinical manifestations, it is considered to be related to “blood in urine”, “lumbago”, “deficiency labor”, “kidney wind”, “edema”, “guangs” and other pathologies. At present, most scholars believe that this disease is caused by the deficiency of the root and the symptoms, and the intermingling of deficiency and reality. Professor Zhang Qi believes that Yin deficiency of liver and kidney or Qi-Yin deficiency is the internal factor that leads to the development of IgA nephropathy hematuria; while Damp-Heat poisonous evil and Blood stasis are the factors that cause the onset and aggravation of IgA nephropathy hematuria, and the combination of internal and external evil is the cause of this disease. According to Prof. Nie Lifang, the etiology is divided into primary and causative factors. The main cause is mostly the deficiency of the spleen and kidney; the causative factors are external evil and overwork, resulting in recurrent attacks and prolonged hematuria in this disease. Prof. Du Yumao believes that the initial pathogenesis of the disease is mostly due to internal heat from yin deficiency and the blockage of the ligaments, which leads to delusional overflow of blood from the lower orifices. Professor Liu Hongwei believes that IgA nephropathy is centered on the kidney, and deficiency of the kidney and injury to the kidney body are the internal causes, and can involve the lung, spleen and liver. The main cause of IgA nephropathy is external evil, especially wind-damp-heat poison. The nature of the disease is a mixed evidence of deficiency and reality, and the transformation of the disease mechanism is mostly in the process of Yin deficiency → Qi and Yin deficiency → Yin and Yang deficiency. Professor Sun Wei believes that IgA nephropathy is a Qi deficiency based disease, related to liver, spleen and kidney. The disease starts from deficiency of kidney qi, spleen qi, liver qi and lung qi, resulting in pathological factors of dampness, heat, stagnation and blood stasis, resulting in more deficiency, dampness, heat, stagnation and blood stasis are difficult to get rid of, and eventually the spleen and kidney fail, dampness and toxicity are contained, resulting in severe kidney labor. Professor Wang Yongjun firstly proposed the etiology and pathogenesis of rheumatism causing nephropathy, and believed that the pathogenesis of IgA nephropathy is the invasion of wind and dampness by the deficiency of kidney qi, resulting in the formation of kidney wind and kidney deficiency symptoms of IgA nephropathy; then the disease enters the ligament and becomes paralyzed for a long time, resulting in the formation of kidney ligament stasis and kidney micro-Y accumulation; then the qi-transformation function of the kidney is further weakened and decayed, and the accumulation of deficiency becomes labor, resulting in the formation of drowning toxicity. It can be seen that in the understanding of the etiology of IgA nephropathy, most physicians believe that IgAN is a mixed evidence of deficiency and reality. It should be noted that even if the same deficiency is mixed with reality, there are differences between reality due to deficiency and deficiency due to reality, so the clinical evidence must be based on the specific circumstances, distinguish the strength and weakness of the evil, as well as the long and temporary, light and serious, and urgent, in order to make the correct treatment, to achieve the “treatment of the disease to the root” requirements. At present, there is no unified standard of identification and typing for the treatment of IgA nephropathy in Chinese medicine, and each doctor treats the disease according to his own experience and uses the prescriptions and medicines, which can achieve certain efficacy, but its objectivity, practicality and repetitiveness limit the popularization, and also reflect the urgent need to standardize and improve the content of IgA nephropathy identification, in order to facilitate the collaboration of national multicenter research on a large sample to explore the It also reflects the urgent need to standardize and improve the identification of IgA nephropathy, so as to facilitate national multicenter collaborative studies with large samples and explore the pathogenesis and nature of IgA nephropathy. As IgA nephropathy is recurrent and persistent, most scholars now advocate identifying the stage of the disease first, and then identifying the evidence on the basis of the stage, thus combining the identification of the stage of the disease with the identification of the type of evidence. For example, Prof. Nie Lifang divided the disease into the acute phase with wind-heat in the lung and stomach, heart-fire, damp-heat in the stomach and intestines, and damp-heat in the bladder, and the chronic phase with deficiency in spleen and kidney qi and yin, deficiency in liver and kidney yin, deficiency in spleen and kidney qi, and deficiency in spleen and kidney yang; Prof. Chen Yiping divided the acute phase into wind-heat disturbance, damp-heat in the lower jiao, and heart-fire. Prof. Chen Yiping divided the acute phase of the disease into wind-heat disturbance, damp-heat in the lower jiao, and hyperactive heart fire, and the chronic phase into yin-deficiency and fire, qi-deficiency and blood stagnation, while the chronic phase was divided into spleen-kidney qi-deficiency, liver-kidney yin-deficiency, spleen-kidney yang-deficiency, and qi-stagnation and blood stagnation. Some scholars divided the disease into initial, stable and late stages, and considered that the initial stage of the disease was in the lung and kidney, the stable stage was in the spleen and kidney, and the late stage of the disease was in the liver and kidney with prolonged illness. Other scholars classify the disease according to normal kidney function and abnormal kidney function. For example, Prof. Lu Renhe divided the former into four types of symptoms, including wind-cold-heat attacking the lung guard, gastrointestinal damp-heat and unfavorable qi-mechanism, liver-depression and fire and qi-yin deficiency, and the latter into three types, including qi-deficiency, blood-deficiency and yin-deficiency, and ten symptoms, including liver-depression and qi-stagnation. 2.2 Classification of evidence by hematuria/proteinuria Hematuria and proteinuria are the most common clinical manifestations of IgA nephropathy, therefore, some scholars propose to classify hematuria and proteinuria for evidence identification. Professor Zhen-Sheng Shi classified hematuria as heat-injured blood circulation type, kidney-yin deficiency type, spleen qi weakness type, and blood stasis and internal obstruction type; and proteinuria as spleen qi deficiency type, spleen-kidney qi deficiency type, qi-yin deficiency type, triple-jiao qi stagnation type, blood stasis and internal obstruction type, and damp-heat internalization type. Prof. Jin Zhongda divided IgA nephropathy with predominantly hematuria into four types of evidence: Yin deficiency and internal heat, Qi-Yin deficiency, Qi deficiency of the spleen and kidney, and stasis of blood obstruction; those with predominantly proteinuria were divided into three types of evidence: Qi deficiency of the spleen and kidney, Qi-Yin deficiency, and Yang deficiency of the spleen and kidney. Prof. Liu Baohou divided IgA nephropathy with hematuria as the main clinical manifestation into four types: damp-heat injury, internal heat of yin deficiency, deficiency of both qi and yin, and deficiency of spleen and kidney qi. Professor Luo Yuezhong believes that the TCM evidence types of IgA nephropathy patients with simple hematuria are mainly liver-kidney yin deficiency and qi-yin two deficiencies, while patients with hematuria with mild to moderate proteinuria mainly focus on qi-yin two deficiencies and yin-yang two deficiencies, and patients with high proteinuria and renal insufficiency mainly focus on yin-yang two deficiencies. As IgA nephropathy is a modern medical name, its diagnosis must be confirmed by renal biopsy and based on renal immunopathology, therefore, more and more scholars agree that the TCM understanding of this disease also needs to be based on the combination of macroscopic clinical manifestations and microscopic renal pathological changes. Prof. Du Yumao combined with the theory of Chinese medicine pathogenesis that the pathological changes of glomerular thylakoid hyperplasia, fibrosis, sclerosis, vitreous changes, glomerular adhesions, tubular atrophy and interstitial damage in IgA nephropathy are attributed to the blockage of blood and blood stasis, blood stagnation and qi stagnation in the renal vasculature, which leads to tissue hyperplasia and sclerosis degeneration. Professor Yang believes that macroscopically, IgA nephropathy is characterized by recurrent episodes of hematuria and proteinuria, varying degrees of sore throat and edema, which are persistent and difficult to heal, and are easily triggered by external sensation and exertion, all of which are consistent with the pathogenic characteristics of damp-heat and blood stasis in traditional Chinese medicine. The glomerular tract hyperplasia, fibrosis, sclerosis, glassy changes, balloon adhesions, tubular atrophy, and interstitial damage are also consistent with stasis of blood. According to Prof. Li Xue-Ming, all patients with intra-glomerular crescent formation, or partial glomerular sclerosis, or moderate or severe thylakoid hyperplasia can be treated with drugs that activate blood circulation and resolve blood stasis. Many other physicians have also explored the TCM identification of IgA nephropathy through the correlation between renal pathology and TCM identification and typing. Professor Chen Xiangmei et al. studied the relationship between TCM differentiation and renal pathology in 286 cases of IgA nephropathy, showing that the pathological changes in the spleen-lung qi deficiency and qi-yin deficiency were mild, with Lee’s grading predominantly in grades I-III; the pathological changes in the liver-kidney yin deficiency were heavy, with grades III-IV; the pathological changes in the spleen-kidney yang deficiency were the heaviest, with grades IV-V; the differentiation and grading correlated significantly with Lee’s grading. ‘s classification correlated significantly, therefore, the evolution process of TCM evidence type from Qi deficiency → Qi and Yin deficiency → Liver and Kidney Yin deficiency → Spleen and Kidney Yang deficiency reflected the progressive aggravation of IgA kidney pathology to a certain extent. The clinical and pathological correlation study of 128 patients with IgA nephropathy with renal pathology of spherical and segmental sclerosis and Lee’s grade III or higher showed that the evolution of pure deficiency to deficiency-solid mixed evidence in these patients is a signal of disease progression, and the degree and extent of deficiency-solid mixed evidence (including the crossover and overlap of each evidence type) is important for The degree and extent of the mixed deficiency and actual symptoms (including the intersection and overlap of the symptoms) are important for judging the prognosis of disease. Wang Yongjun et al. analyzed the correlation between the four clinical symptoms and renal pathology in 1148 patients with IgA nephropathy: renal deficiency, stasis paralysis, rheumatism, and hepatic wind, and the results showed a good correlation between the types of symptoms and renal pathology. The severity of the katafuchi score and the renal tubulointerstitial and renal vascular scores of IgA nephropathy, as well as the chronicity index of Andreoli score, showed that the severity of liver wind > rheumatism > kidney deficiency > paralysis; while the glomerular score of the katafuchi score showed that liver wind and rheumatism > kidney deficiency > paralysis; the activity index of Andreoli score showed that rheumatism and liver wind were the most severe.