Variations in serum complement in the nephrotic syndrome and other forms of renal disease

Abstract

Serial complement determinations have been carried out in 75 patients suffering from various forms of renal disease. Very low serum complement levels were found during the early active stage of acute nephritis, but these low values returned to normal in most cases in parallel with clinical recovery. Moderately depressed complement levels were found in subacute nephritis. These values returned to normal whether clinical recovery occurred or whether the patient progressed to chronic nephritis with or without terminal renal failure. Cases of chronic nephritis, chronic pyelonephritis or of chronic renal damage from other causes gave normal complement values.

Serum complement values were similar when cases with and without the nephrotic syndrome were matched, as far as possible, according to the underlying disease process. Cases of the nephrotic syndrome of undetermined aetiology were divisible into a group with subnormal values and a group with persistently normal values. It is suggested on the basis of the foregoing observations that these two groups may be aetiologically distinct.

The values of serial complement determinations as aids to diagnosis, the control of therapy (especially corticosteroid therapy) and prognosis in renal disease is appraised.