Ten patients with Henoch-Schöenlein
purpura (HSP) were selected for study because their early renal biopsies showed focal and segmental hypercellularity, with
IgA present only in deposits at the periphery of the lobules. Mesangial deposits of
IgA were absent. All had laboratory evidence of
nephrotic syndrome and/or renal compromise. The glomerular hypercellularity was largely the result of the infiltration of monocytes whose cytoplasm often contained tubular lysosomes and wrapping lysosomal membranes, evidence of monocyte activation. Mean levels of C3 were normal but those of C4 and
properdin significantly depressed. This
complement profile, as well as a glomerular monocytic infiltrate, are also seen in essential
cryoglobulinemia in the adult. Of follow-up biopsies in six patients, the glomeruli were normal in three, with no
IgA deposition. In the other three, mesangial deposits of
IgA typical of HSP were present. The initial focal-segmental glomerulitis of these patients appeared to be the benign first phase of a disease which had the potential to culminate in mesangial
IgA deposition. Patients like the three who escaped mesangial
IgA would be among those responsible for the observed dissociation between severity of the initial illness and ultimate prognosis.