The article by Vilardell et al1 of a patient afflicted with pseudolymphoma and Sjögren's syndrome associated with IgA nephropathy provides another example of multisystem disease associated with renal biopsy findings consistent with IgA nephropathy. As pointed out in my editorial, not all patients with renal mesangium deposits of IgA, the hallmark of IgA nephropathy, have isolated hematuria as the sole manifestation. Rather, a glomerular lesion indistinguishable from that seen in patients with IgA nephropathy can be seen in association with multisystem involvement. Eye involvement in the form of scleritis and skin manifestations (ie, dermatitis herpetiformis, mycosis fungoides) has been shown to occur in some patients with hematuria and mesangial deposition of IgA. It is possible that circulating immune complexes, containing IgA, participate in the development of multisystem involvement in these patients. The primary mechanism underlying overproduction of IgA in some patients may be that of abnormal T-cell function. Either