Focal segmental glomerulosclerosis in adults.

The lesion of focal segmental glomerulosclerosis (FSGS) presents even greater problems of definition, interpretation and treatment in adults than it does in children, to the point where the specificity and utility of the appearance can even be questioned. The histological diagnosis of FSGS in adults can be interpreted only if the clinical circumstances are known, but a group of nephrotic patients with FSGS can be separated from a much larger group of non-specific, probably secondary but similar lesions arising in many circumstances. This group appears even so to have a diverse aetiology, the majority being idiopathic, but a significant minority showing a family history and/or mutations in genes relating to several intracellular or surface podocyte proteins, as discussed in other articles in this symposium. This heterogeneity makes conclusions with regard to prognosis and treatment difficult to draw. Today, in contrast to 20 or even 10 years ago, it seems useful to treat all adult nephrotic patients with FSGS using an adequate course of corticosteroids lasting at least 4-6 months to establish whether they fall or not into the 20-30% who will respond to this treatment with decrease or loss of proteinuria. The prognosis of such responders (who may well suffer relapse) is relatively benign with regard to renal function, but the majority of the remainder evolve into renal failure. Their management remains a source of controversy in the absence of a proper database of randomized trials: more prolonged (up to 24 months) use of lower-dose corticosteroids with cyclosporine for 12 months or more has support from uncontrolled studies, but cyclophosphamide appears to be of less obvious benefit.