Findings of the kidney biopsy specimens from patient 2. (A) Glomerular mesangial expansion and hypercellularity was observed (arrowheads). (PAS staining, × 400). (B) Glomerular mesangial deposits for IgA antisera were observed (immunofluorescence study, × 400). (C) Approximately 10% tubulointerstitial fibrosis of the cortex was observed (Azan staining, ×100). (D) Ultrastructural evaluation revealed the electron-dense deposits in the mesangium (arrowheads, transmission electron microscopy, ×4000). Abbreviation: IgA, Immunoglobulin A; PAS, Periodic acid Shiff.