In pediatric purpura nephritis, “stasis” and “heat” are the key to the pathogenesis, and the treatment proposes “clearing heat and detoxifying, cooling blood and dispelling wind in the early stage; detoxifying and resolving stasis, cooling blood and stopping bleeding in the middle stage; nourishing Yin and invigorating blood, nourishing kidney and clearing profit in the late stage. “The treatment is to clear the heat and detoxify the blood and dispel the wind in the early stage; to detoxify the blood and remove stasis, cool the blood and stop the bleeding in the middle stage; to nourish the yin and invigorate the blood and nourish the kidney to clear the profit in the late stage. The kidney damage caused by allergic purpura is called allergic purpura nephritis (HSPN), or purpura nephritis for short. The clinical symptoms are mainly recurrent skin purpura, visual or microscopic hematuria, accompanied by proteinuria, swelling, hypertension, etc. Serious cases may develop into chronic renal insufficiency. It belongs to the category of “epistaxis”, “blood evidence”, “blood in urine” and “edema” in Chinese medicine. The severity of renal damage is closely related to the prognosis of this disease. Purpura, hematuria and proteinuria often recur during the course of the disease and are difficult to be cured. Western medicine is mostly based on clinical or pathological typing and treatment with symptomatic and hormonal, immunosuppressive and anticoagulant drugs, but the efficacy is poor and the toxic side effects are great. In recent years, the study of purpura nephritis has received much attention. Director Sun Yichou, in his long-term clinical work, has continuously practiced and innovated, and formed a set of his own treatment characteristics and medication methods, with remarkable efficacy, which has cleared the disease for the majority of children. The author was fortunate enough to study with his mentor and listen to his teachings, and has benefited greatly from them. In terms of etiology, the instructor emphasized “wind, dampness, heat, toxicity, stasis and deficiency”, and believed that deficiency of positive energy and dysfunction of the body’s immune function are the internal causes, while feeling external evil is the causative factor. The disease is caused by internal heat and toxicity, fire and blood, blood overflow, blockage of blood vessels, and internal stagnation of water and fluid. The formation of blood stasis is closely related to “heat, toxicity, dampness and deficiency”. As Wang Qingren said in his book “The blood is tormented by heat and becomes clotted”. Stasis is caused by heat, and heat and stasis are intertwined, often causing the evil heat to linger and the stagnant blood to stay for a long time. As the saying goes, “heat is attached to blood and the more it feels entangled, the more the blood gets heat and the more it becomes solid”. Dampness obstructs the luo, hinders qi and hurts yang, yang does not spread, the blood does not flow smoothly, “qi travels and blood travels, qi stagnates and blood stasis”, so it becomes stasis for a long time, as Zhu Danxi said, “blood subject to dampness and heat, long will be condensed”. Blood stasis blocks the meridians and channels, the fluid loses its distribution and turns into dampness, the dampness and stasis are mutually knotted, and the gel is difficult to be transformed; the deficiency of the viscera and internal organs in prolonged illness, the impetus is weak, the blood travels slowly and coagulates; the Yin deficiency and fire are vigorous, and the refined blood becomes stasis. When stasis and heat are formed, stasis blocks the veins and ligaments, blood flow is obstructed and does not follow the normal path and overflows outside the veins to become purpura; evil heat is contained in the blood part of the muscle surface, forcing the blood to travel, overflowing the skin orifices to develop epistaxis. Stasis and heat are mutually affected, blocking and fighting, forming a vicious circle, aggravating the disease and making it difficult to heal. 2. Staged treatment, add and subtract according to the symptoms The teacher believes that: purpura nephritis is often characterized by skin purpura accompanied by kidney damage in children at the beginning of the disease, “wind, heat, dampness, toxicity and stasis” is the main cause, the pathogenesis of the disease is “fire” as the key, the main evidence is actual, or wind-heat injury, or blood-heat delusion. The late stage of the disease is prolonged, consuming Qi and injuring Yin, often with kidney damage as the main cause, with clinical manifestations of persistent or repeated hematuria and proteinuria, with Yin deficiency and fire or Qi and Yin deficiency as the main pathogenic mechanism, which is the main deficiency and the symptoms. Therefore, the treatment proposes a trilogy of “clearing heat and removing toxins and cooling the blood to dispel wind in the early stage; resolving toxins and stasis, cooling the blood to stop bleeding in the middle stage; nourishing yin and invigorating blood, nourishing the kidney and clearing profit in the late stage”, and advocates the idea that the treatment principle of invigorating blood to remove stasis and desensitizing and regulating exemption should be used throughout. The treatment is based on dispelling wind, relieving dampness, clearing heat, detoxifying the toxin, cooling the blood, resolving blood stasis, nourishing Yin, benefiting Qi and nourishing Blood. In the early stage of the disease, the formula for wind-heat injury is reduced by Yin Qiao Defeat Poison San, while the formula for blood-heat delusion is reduced by Rhizoma Dihuang Tang; in the late stage, the formula for yin deficiency and fire is increased by Zhi Bai Dihuang Wan combined with Er Zhi Wan, and the formula for deficiency of both qi and yin is advanced by Ginseng Qi Dihuang Tang. Adding and subtracting to the symptoms: swollen and painful joints, add cow’s knee, lonicera, roasted frankincense, roasted myrrh; abdominal pain, add white peony, yanhuosuo, mullein; intestinal bleeding, add elm charcoal, acacia charcoal; blood in the urine, add cattail charcoal, cyperus, lotus root charcoal; edema, add zedoary, plantain, poria bark; urine protein, add cornus, cape flower; urine leukocytes, add white mullein, cypress, six one san; increased cholesterol, add rhubarb, raw hawthorn; increased blood pressure, add If purpura is recurrent, add Bai Xian Pi, Di Shen Zi and Bitter Ginseng; if there is a tube type in urine, add Cat’s Claw. The main reason for this is that it is not a good idea to use the same method of treatment. The stasis of blood and heat injures the kidney ligament, the evil heat injects down the bladder through the meridian, resulting in hematuria; the stasis of blood blocks the kidney ligament, the kidney’s qi-transformation and sealing are not in order, the essence is leaking out, resulting in proteinuria; the stasis of blood blocks the kidney, the kidney loses the function of main water, the turbid yin cannot be properly leaked out and stored in the body, resulting in edema. In the course of the disease, heat and toxin are abundant and torment the blood, so the blood is sticky and thick and stagnates in the veins; or heat injures the blood channels and forces the blood to move delicately, so the blood overflows outside the veins, thus forming the evidence of “stasis of blood” in Chinese medicine, which has become stasis of blood and can turn heat into toxin and further torment the blood. The disease is prolonged, stasis and heat injure yin and consume qi, even if the heat and toxicity decreases, children with mainly deficiency evidence can also have blood stagnation in the veins or overflow in the veins due to yin deficiency and blood astringency, or qi deficiency and blood loss, thus resulting in stasis of blood evidence. Western medical studies have confirmed that children with allergic purpura nephritis have alterations in blood rheological indices such as whole blood viscosity, plasma viscosity, and fibrinogen, which have been shown to be positively correlated with blood stasis evidence in TCM [1]. Given the presence of macroscopic stasis and microscopic stasis in children with allergic purpura, treatment to activate blood stasis should be carried out throughout the treatment of this disease. Therefore, stasis of blood is one of the pathological mechanisms throughout the course of purpura nephritis. Based on this pathological mechanism, the instructor summarized the experience of previous authors and combined with his own clinical practice, based on the identification of evidence, he proposed that the treatment of purpura nephritis should be based on the basic method of cooling blood, resolving blood stasis and clearing the ligaments, and on the basis of Rhizoma Rhizoma Dihuang Tang, he developed the formula of cooling blood, resolving blood stasis and clearing the ligaments [Buffalo Horns (first decoction) 20 g, Radix et Rhizoma 10 g, Red Peony 10 g, Mudanpi 10 g, Chuan Niu Knee 10 g, Zi Cao 15 g, Chicken Blood Vine 12 g, Xi Cao 15 g, 10 g each of large and small thistle, 10 g of cicada molasses, and 3 g of licorice]. The formula was further used to develop Dan Shao granules. Animal experiments confirmed that Dan Shao granules can improve auricular microcirculation, inhibit capillary permeability and skin allergic reactions in mice, and have good effects on improving microcirculation, anti-inflammation and inhibiting type I metaplasia [2], and clinical trials also showed good efficacy. The most important thing is that it is the most important part of the treatment. If the evil heat burns the kidney complex, or if the heat toxin is contained within the kidney for a long time, it consumes the qi and hurts the yin, and the kidney yin is deficient and the fire is exuberant, and the deficiency fire burns the veins and lanes, then hematuria is seen. Dampness is the cause of pathogenesis and the pathological product of the pathogenesis process. When water and dampness invade the body, the spleen loses its health, and the spleen loses its ability to raise the clear and lower the turbidity, so that the essence and microscopic substances leak down and become proteinuria. Dampness and heat are often intertwined, “dampness and heat stay, protein is difficult to eliminate”, resulting in a lingering condition. The two “stasis and heat” are key in the pathogenesis of the disease. The kidney is the innate base, children often have surplus Yang, Yin is often insufficient, the kidney is often deficient, the heat does not go, depletion of qi and Yin, long will be and kidney, resulting in kidney complex damage. In modern medicine, it is believed that allergic purpura is a systemic small vasculitis, and the kidney, because of its special structure, is easily involved, and a study found that nearly 1/3 of children have clinical manifestations of kidney injury, and almost 100% of kidney biopsies have different degrees of kidney damage during the course of the disease [3]. Therefore, in the prevention of purpura complicating kidney damage, the instructor proposed the idea of “when we see the disease of purpura, we know that purpura transmits to kidney, so we should nourish the kidney first” according to the old saying of “the upper work treats the untreated disease”. For children with allergic purpura, those who have elevated urine microalbumin, β2-microglobulin or urine NAG enzyme in early stage, they should be given nourishing kidney and clearing products in order to first stabilize the uninfected organs and prevent kidney damage. Practice has shown that early application of nourishing and clearing products can reduce the incidence of kidney damage and mitigate the degree of kidney injury. For the diagnosis and treatment of purpura nephritis, the draft of the Zhuhai Conference [4] is still followed in China, and glucocorticoids are the main drug in the treatment of those with nephrotic syndrome type or pathology grade IIIb or IV or above. The mentor believes that hormones are masculine products, and in the process of long-term application in large doses often lead to hyperactivity of kidney yang and depletion of kidney yin, which then causes deficiency of yin of liver, heart and stomach with hyperactivity of liver yang, exuberance of heart fire and exuberance of stomach fire, resulting in a school of clinical manifestations of yin deficiency and exuberance of fire. When the disease is under control and in the stage of gradual reduction of treatment, Yin deficiency is transformed into Yang deficiency and both Yin and Yang are deficient, at this time, we should benefit Qi and strengthen the spleen, nourish Yin and tonify the kidney. If yin deficiency is the main cause, nourish yin and tonify kidneys at the same time with yang medicines; if spleen and kidney yang deficiency is the main cause, strengthen the spleen and warm the kidneys while nourishing yin products. This is the so-called “good at nourishing Yang, must seek Yang in Yin, good at nourishing Yin, must seek Yin in Yang”. As for the use of kidney tonics to warm the Yang, the instructor believes that these herbal medicines have hormone-like effects without the side effects of exogenous hormones, and with the different periods and doses of hormone use, they can maintain the balance of yin and yang in the body and improve and restore the morphological changes and functional disorders of the endocrine system caused by hormones. Therefore, kidney tonics can be used to replace oral hormones for the purpose of withdrawing hormones. After discontinuing hormones, warming agents for the spleen and kidney should be given to prevent recurrence of the disease. Through the organic combination of the above Chinese and Western medicine treatment methods, the disease was successfully controlled and gradually healed. 6. Case example: Hu, female, 7 years and 8 months old, was first diagnosed in February 2007. The child had intermittent episodes of rash on both lower extremities for 1 month and then developed abnormal urinalysis, and had been taking prednisone tablets intermittently in an outside hospital for abdominal pain and joint swelling and pain. On examination: the child had a scattered dark red rash on both lower extremities, which was above the skin and did not fade when pressed, mild puffiness on the face, heat in the hands and feet, red tongue with thin yellow fur, dark red veins at the base of the tongue, and fine pulse. Routine urine examination shows: protein ++++, occult blood ++++, blood leukocyte, platelet count, clotting time, liver and kidney function are normal. Traditional Chinese medicine diagnosis: blood evidence (epistaxis, blood in urine). Western medicine diagnosis: allergic purpura nephritis. Prednisone 50 mg/d [2 mg/(kg?d)] was given orally. The diagnosis in Ancestral medicine is Yin deficiency, heat and evil within the body, forcing the blood to move freely and blocking the blood stasis. The treatment is to nourish yin, clear heat, cool blood, resolve blood stasis, and open the ligaments. The formula of cool blood, resolve blood stasis, and open the ligaments was added and reduced [Sheng Di Huang 10 g, Red Peony 10 g, Mudan Pi 10 g, Comfrey 15 g, Chuan Niu Knee 10 g, Lady’s Mantle 10 g, Dry Lotus Grass 15 g, Chicken Blood Vine 12 g, Xi Cao 15 g, Big and Small Thistle 10 g each, Cicadelle 10 g, Fishy Herb 15 g, Cornus Officinalis 15 g, Liu Yi San (packet) 15 g], with increasing loss according to the symptoms. The rash was controlled after 2 weeks, and the urine protein turned negative after 4 weeks of medication. The child developed a full-moon face, facial acne, self-consciousness of weakness of the lower limbs and knees, heat in the heart of the hands and feet, dry mouth, irritability, easy to eat and hunger, red tongue, yellowish greasy coating, and fine pulse. The evidence indicates that there is deficiency of kidney yin and internal obstruction of damp-heat. He changed the formula to Zhi Bai Di Huang Tang with addition and subtraction [Zhi Mu 10 g, Huang Bai 6 g, Sheng Di Huang 10 g, Mudan Pi 10 g, Atractylodes macrocephala 10 g, Chuan Niu Knee 10 g, Feminine Zizi 10 g, Dried Lotus Grass 15 g, Chicken Blood Vine 12 g, Xi Cao 15 g, Large and Small Thistle 10 g, Liu Yi San (packet) 15 g], and made adjustments according to the symptoms. After the above symptoms gradually improved and the urine protein turned negative for 2 weeks, the hormone was changed to alternate day doses and the dosage was gradually reduced (5 mg of prednisone per month, and 2.5 mg per month when the dosage was reduced to about 10 mg). At the beginning of the reduction, the dosage was followed by Zhi Bai Di Huang Tang; at the end of the reduction, the dosage was supplemented with warming Yang products such as bone marrow and Epimedium, and the dosage of warming Yang medicine was increased with the reduction of hormone. In April 2008, the hormone was withdrawn, the urine protein remained negative and the purpura did not recur, followed by Chinese herbal medicine for 3 months, the condition was stable.