Adult nephrotic syndrome: non-specific strategies for treatment.

SUMMARY: Irrespective of aetiology, the nephrotic syndrome presents a range of potentially serious complications. These include thrombo-embolism, infection and hyperlipidaemia. Despite the prevalence of the nephrotic state among renal patients, there has been little prospective analysis of the therapeutic approach to these potentially life-threatening events even though their pathogenesis has been examined in some detail. Most of these complications are more prevalent once the albumin concentration falls below 20 g/L and it is recognized that restoration of serum albumin significantly diminishes their frequency. However, this may be difficult to achieve, especially in adults. The problems of thrombo-embolism and infection are of immediate concern but, in persistent cases, the additional issues of hyperlipidaemia and loss of bone density also require consideration for therapy. Thus, in addition to specific attempts to reduce proteinuria, it is recommended that high-risk nephrotic patients receive anticoagulation, pneumococcal vaccination and lipid lowering therapy. Strategies for the preservation of bone density should also be considered, particularly in patients who receive high-dose corticosteroids. Among a range of non-specific treatments for proteinuria, angiotensin-converting enzyme inhibitors appear best in terms of efficacy and safety. Prospective trials are required to clarify the longitudinal impact of these generic strategies on the protection of the persistently nephrotic patient. A significant percentage of patients with the nephrotic syndrome will remain heavily proteinuric despite vigorous attempts to modify its course with specific, therapeutic regimens. In the event that proteinuria remains sufficiently heavy to maintain the nephrotic state, with its inherent risks, then the nephrologist is required to consider additional strategies to protect the patient from escalating harm. Moreover, the prolonged use of potentially dangerous agents, such as steroids and cytotoxic agents, in the hope of achieving a satisfactory remission, provides further clinical risks for the patient. This review will not address the specific therapeutic regimens currently in use for the treatment of patients with nephrotic syndrome. Rather, it will examine those policies that are applicable to all adult nephrotic patients, irrespective of aetiology. There is little prospective data on these protective strategies even though there have been major advances in the safety and efficacy of therapeutic agents.