Isolated protein with diffuse membranous glomrlneph, unsp

This code signifies the presence of protein in the urine (proteinuria) without other signs of nephrotic syndrome, specifically attributed to diffuse membranous glomerulonephritis. This kidney disorder involves thickening of the glomerular basement membrane due to immune complex deposition, leading to impaired filtration.

Apply this code when documentation explicitly states isolated proteinuria and a biopsy-confirmed diagnosis of diffuse membranous glomerulonephritis. This diagnosis is typically made after ruling out other causes of proteinuria and confirming the specific histological findings.

• Ensure documentation specifies "isolated proteinuria" and "diffuse membranous glomerulonephritis."
• Do not code with N04.20 (membranous nephropathy NOS with nephrotic syndrome) due to the Excludes1 note.
• If nephrotic syndrome is also present, a different code from category N04 would be more appropriate.