A case of membranous nephropathy associated with chronic sinusitis.

Here we report a case of a 71-year-old Japanese woman with membranous nephropathy complicated with chronic sinusitis. The patient visited our hospital for treatment of edema and proteinuria, and was diagnosed as nephrotic syndrome with serum total protein 7.5 g/dL, albumin 2.2 g/dL and urine protein 3.7 g/day. Renal biopsy revealed membranous glomerulonephritis with tubulointerstitial nephritis. She had suffered from chronic sinusitis for several years. Laboratory tests showed that immunoglobulin G (IgG) and soluble interleukin-2 receptor (sIL-2R) were markedly increased (3,233 mg/dL and 5,110 U/mL, respectively) and Gallium scintigraphy showed abnormal accumulation to the paranasal sinus. After operation for chronic sinusitis, the levels of IgG and sIL-2R were decreased, and nephrotic syndrome was improved without any other specific treatments. It is known that various diseases, including membranous nephropathy and sinusitis, are caused by T-cell dysfunction. Thus, we suspect the pathogenetic link between membranous nephropathy and chronic sinusitis in this case, most probably through T-cell dysfunction.