McCloskey Oonagh, Maxwell Alexander P
Practitioner. 2017 Feb;261(1801):11-5.
Nephrotic syndrome is defined by a triad of clinical features: oedema, substantial proteinuria (> 3.5 g/24 hours) and hypoalbuminaemia (< 30 g/L). It is often associated with hyperlipidaemia, thromboembolism and an increased risk of infection. Nephrotic syndrome develops following pathological injury to renal glomeruli. This may be a primary problem, with a disease specific to the kidneys, or secondary to a systemic disorder such as diabetes mellitus. The most common cause in children is minimal change glomerulonephritis. In white adults, nephrotic syndrome is most frequently due to membranous nephropathy whereas in populations of African ancestry the most common cause of nephrotic syndrome is focal segmental glomerulosclerosis. Diabetic nephropathy is the most common multisystem disease that can cause nephrotic syndrome. Patients typically present with periorbital oedema (most noticeable in the morning) or dependent pitting oedema (more common later in the day). Proteinuria should be documented by a quantitative measurement e.g. urine protein: creatinine ratio (PCR) or albumin: creatinine ratio (ACR). PCR > 300-350 mg/mmol indicates nephrotic range proteinuria. Urgent referral to a nephrologist (ideally within 2 weeks) is necessary and a renal biopsy is usually performed. This will establish what form of glomerular disease is responsible. Additional tests may be undertaken to assess if nephrotic syndrome is secondary to another disorder e.g. systemic lupus erythematosus or amyloidosis.
水肿、大量蛋白尿（>3.5克/24小时）和低白蛋白血症（<30克/升）。它常与高脂血症、血栓栓塞及感染风险增加相关。肾病综合征是在肾小球发生病理损伤后出现的。这可能是原发性问题，即肾脏特有的疾病，也可能继发于全身性疾病，如糖尿病。儿童中最常见的病因是微小病变性肾小球肾炎。在白人成年人中，肾病综合征最常见的病因是膜性肾病，而在非洲裔人群中，肾病综合征最常见的病因是局灶节段性肾小球硬化。糖尿病肾病是最常见的可导致肾病综合征的多系统疾病。患者通常表现为眶周水肿（早晨最明显）或下垂性凹陷性水肿（一天中晚些时候更常见）。蛋白尿应以定量测量记录，例如尿蛋白：肌酐比值（PCR）或白蛋白：肌酐比值（ACR）。PCR>300 - 350毫克/毫摩尔表明为肾病范围蛋白尿。需要紧急转诊至肾病科医生处（理想情况下在2周内），通常要进行肾活检。这将确定是哪种形式的肾小球疾病所致。可能还需进行其他检查以评估肾病综合征是否继发于其他疾病，例如系统性红斑狼疮或淀粉样变性。
