Renal Impairment of Proximal Tubular Injury Caused by Red Yeast Rice Supplement: Report of 2 Cases.

Introduction: Drug-induced tubulointerstitial injury is a common cause of renal impairment. Since the mechanisms of drug-induced tubular injury are diverse, various treatment approaches are needed according to the pathogenesis. Renal biopsy is indispensable to determine not only the pathological diagnosis, but also the underlying mechanism, and to guide appropriate treatment.

Focal Light Chain Proximal Tubulopathy Complicated by Monoclonal Gammopathy of Undetermined Significance/Smoldering Multiple Myeloma Successfully Diagnosed by Immunofluorescence on Pronase-Digested Paraffin Section: Reports of Two Cases and Review of the Literature.

Light chain proximal tubulopathy (LCPT) is a rare type of paraprotein-related disease (PRDs) characterized by monoclonal free light chain (FLC) deposition in proximal tubular epithelial cells (PTECs). A diagnosis of LCPT requires identification of FLC deposition in PTECs; however, FLC luminescence defects in immunofluorescence staining using frozen tissue (IF-F), regarded as "masked LCPT", are occasionally encountered. We describe two cases of focal masked LCPT in monoclonal gammopathy of undetermined significance (MGUS) or smoldering multiple myeloma (SMM) diagnosed by IF in formalin-fixed, paraffin-embedded tissue sections following pronase digestion (IF-P) rather than by IF-F.

Lupus-like membranous nephropathy during the postpartum period expressing glomerular antigens exostosin 1/exostosin 2 and phospholipase A2 receptor: a case report.

Recently, several target antigens of membranous nephropathy (MN), such as phospholipase A2 receptor (PLA2R) and exostosin 1/exostosin 2 (EXT1/2), have been discovered. A 30-year-old woman was referred to our hospital with nephrotic range proteinuria and microscopic hematuria. She was first noted to have proteinuria before pregnancy, and her proteinuria worsened in the postpartum period.

Clinico-Pathogenic Similarities and Differences between Infection-Related Glomerulonephritis and C3 Glomerulopathy.

Recently, the comprehensive concept of "infection-related glomerulonephritis (IRGN)" has replaced that of postinfectious glomerulonephritis (PIGN) because of the diverse infection patterns, epidemiology, clinical features, and pathogenesis. In addition to evidence of infection, hypocomplementemia particularly depresses serum complement 3 (C3), with endocapillary proliferative and exudative GN developing into membranoproliferative glomerulonephritis (MPGN); also, C3-dominant or co-dominant glomerular immunofluorescence staining is central for diagnosing IRGN. Moreover, nephritis-associated plasmin receptor (NAPlr), originally isolated from the cytoplasmic fraction of group A , is vital as an essential inducer of C3-dominant glomerular injury and is a key diagnostic biomarker for IRGN.

Long-term clinical course of immunotactoid glomerulopathy complicated with diffuse large B-cell lymphoma.

We report a case of immunotactoid glomerulopathy (ITG) complicated with diffuse large B-cell lymphoma (DLBCL). A 68-year-old woman presented with leg edema and was diagnosed with nephrotic syndrome (NS). Renal biopsy revealed ITG.