Previously, we introduced “What is lupus nephritis? Why do you get lupus nephritis?” and other questions. Today, we would like to give you a detailed introduction of what lupus nephritis can show and how to detect lupus nephritis in time. First of all, lupus nephritis most often occurs in women of childbearing age, but it also occurs in children and adolescents, men and menopausal women, but the proportion is significantly reduced. A significant proportion of patients with lupus nephritis have their first manifestation as renal disease. The presentation of these patients has many similarities to that of primary glomerulonephritis. The most common manifestation is the presence of frothy urine, which may sometimes be red in color. Some patients may present with decreased urine output, edema of the eyelids, face, and lower extremities, and in severe edema, chest tightness, breath-holding, shortness of breath after activity, abdominal distention, and loss of appetite. If you have any of the above symptoms, you should go to the hospital for relevant examination in time. Similar to other nephritis, some patients with lupus nephritis may not have any conscious symptoms, but only find abnormal urinalysis or abnormal kidney function during physical examination, as shown by urine routine showing positive urine protein, red blood cells in urine, etc., or even a decrease in serum albumin and an increase in blood creatinine. Therefore, regular comprehensive medical checkups are very important for timely detection of such occult lesions. In addition, hypertension is also one of the very common manifestations of lupus nephritis. Hypertension may be the earliest symptom detected in some patients with lupus nephritis. However, most patients have no conscious symptoms and may have dizziness, headache and blurred vision in severe cases. Whether the hypertension in patients with lupus nephritis can be well controlled plays an important role in the long-term prognosis of the kidney. On the other hand, lupus nephritis is one of the most common manifestations of systemic lupus erythematosus. In contrast, SLE is a disease that can affect various organ systems throughout the body, and its clinical manifestations are very diverse and can present with abnormalities in multiple organs and systems at the same time. Therefore, the majority of patients with lupus nephritis will have more or less simultaneous manifestations of other organs or systemic lesions along with nephropathy. Common manifestations include: 1) fever, fatigue, weakness, weight loss, etc. Many patients repeatedly apply various antibiotics due to fever without significant effect. 2) Skin and mucous membrane lesions: 80% of patients will have various types of rashes, the most typical being erythema in the shape of a butterfly distributed on both cheeks and the bridge of the nose, called butterfly erythema. Other erythema and bleeding spots on the skin (purpura) may also appear. 40% of patients may develop photosensitivity after sun exposure. 30% of patients may develop recurrent mouth ulcers with mild pain. 40% of patients have hair loss. 3) Arthralgia is also a common manifestation of lupus. Usually this arthralgia occurs in multiple joints and is bilaterally symmetrical, but without joint erythema.4) Many patients develop hematologic abnormalities years before the diagnosis of SLE. The most common manifestation is thrombocytopenia, followed by anemia. Laboratory tests may also reveal a decrease in blood leukocytes.5) Thirty percent of patients have cardiovascular symptoms. It can be manifested as pain in the left anterior chest area, shortness of breath, panic, arrhythmia, etc. 6) In some patients, the lesions can accumulate in the lungs, causing fever, dry cough, shortness of breath and even dyspnea, and abnormalities can be seen in chest films or lung CT, but it is not easy to distinguish them from common lung infections. Some patients may also show changes in personality and temperament, susceptibility to suspicion, hallucinations, delusions and other mental abnormalities. These are critical symptoms of lupus and should be treated promptly and actively.8) Some patients may also develop gastrointestinal symptoms, including loss of appetite, abdominal pain, vomiting and diarrhea. The vast majority of these symptoms appear or worsen when the disease is active and disappear or diminish when the disease remits or decreases after treatment. They are an important basis for physicians to judge changes in the disease. For SLE and lupus nephritis, in addition to the above symptoms, there are many abnormalities in laboratory tests. For all patients suspected of having lupus, tests for anti-nuclear antibodies, anti-double-stranded DNA antibodies (anti-dsDNA antibodies), anti-Sm antibodies, serum immunoglobulins and complement are required. Positivity of these antibodies is an important basis for the diagnosis of SLE and lupus nephritis. It can be seen that regular comprehensive health checkups are important for early detection of some insidious nephritis with symptoms. Female patients of childbearing age should pay attention to the presence of other SLE-related symptoms when hematuria and proteinuria occur and seek timely improvement of lupus-related tests for timely and correct diagnosis. Patients with diagnosed SLE and lupus nephritis should also pay attention to observing the changes of these symptoms and inform the doctor in time so that the doctor can make timely judgment on the progress, remission and recurrence of the disease.