While some 20-30% of patients progress to end-stage renal failure 5-20 years after diagnosis, many do not progress. If progression occurs it does so by destruction of glomeruli through focal and segmental glomerular lesions. There are two types of segmental lesions which progress - crescents and focal and segmental hyalinosis and sclerosis. Focal sclerosis without hyalinosis represents the scar of a previous crescent and is not a progressive lesion. A biopsy at the time of diagnosis which shows segmental lesions puts the patient in a more serious prognostic group than ones showing only diffuse mesangial proliferation.

Various clinical features also predict progression. These are shown in Table 1. Of these clinical features which carry a higher risk of progression, three can be reversed by treatment, namely hypertension, proteinuria and a habitually high urinary erythrocyte count (which reflects crescentic lesions). A high urine protein level correlates with segmental glomerular lesions of the focal and segmental hyalinosis and sclerosis. By far the highest risk of progression is seen when heavy proteinuria ( odds ratio for progression = 18) and by its pathological counterpart, focal and segmental hyalinosis and sclerosis (odds ratio for progression = 10).

The next most important clinical feature predicting progression is a habitually high urinary erythrocyte count above 100,000/ml, which correlates with activity on biopsy in the form of crescents and which carries an odds ration for progression of 4.3. High blood pressure, proteinuria and a high urinary erythrocyte count can all be corrected or reduced by treatment.

The available treatments and the evidence for benefit will be presented. If blood pressure, urine protein and the urinary erythrocyte counts are controlled at appropriately low levels progression does not occur in IgA glomerulonephritis.