Uremia is not an independent disease, but a clinical syndrome common to all kinds of advanced kidney disease, a syndrome composed of a series of clinical manifestations that appear when chronic renal failure enters the terminal stage. Some patients with uremia may have no obvious clinical symptoms in the early stage, and some of them may show mild fatigue, poor appetite, anorexia, nausea, vomiting, acid reflux, weight loss, etc. Patients with severe disease may show the above symptoms. In severe cases, patients may experience aggravation of the above symptoms, deep breathing, gastrointestinal bleeding, diarrhea, black stools, and so on. Uremia can lead to volume overload, and it is common to see different degrees of subcutaneous edema (eyelids, both lower limbs) or/and fluid accumulation in the body cavity (thoracic cavity, abdominal cavity), which is prone to elevated blood pressure, left cardiac insufficiency (manifested as tightness in the chest, decreased activity tolerance and even the inability to lie down at night) and cerebral edema. Neurological symptoms can also be combined, with insomnia, poor concentration and memory loss in the early stage. In severe cases, there may be apathy, delirium, convulsions, hallucinations, coma, mental abnormalities and so on. Peripheral neuropathy is also common, and sensory nerve disorder is more significant, the most common is the loss of sensation in the sock-like distribution of the extremities, there can also be numbness, burning or pain sensation in the limbs, the deep reflexes are slowed down or disappeared, and there can be an increase in neuromuscular excitability, such as muscle tremor, spasticity, restless leg syndrome and so on.