Acute nephritis is commonly seen in children, and in cases of acute nephritis in children, it is often preceded by an upper respiratory tract infection or skin infection one to three weeks prior to the onset. Once acute nephritis occurs, the most prominent clinical symptom in patients is gross hematuria, though some individuals only show microscopic hematuria, accompanied by an increase in urinary proteins. Additionally, patients with acute nephritis may experience swelling of the eyelids and lower limbs, especially noticeable swelling of the eyelids and facial area upon waking in the morning. Some patients may also experience elevated blood pressure, leading to symptoms such as dizziness and headache. A few may suffer from nausea, vomiting, loss of appetite, reduced urine output, or even symptoms of acute renal failure.