Five Sequential Evaluations of Renal Histology in a Patient with Light Chain Deposition Disease

Area of Science:

• Nephrology
• Pathology
• Oncology

Background:

• Light chain deposition disease (LCDD) is a rare plasma cell dyscrasia characterized by the deposition of monoclonal immunoglobulin light chains in organs, primarily the kidneys.
• Nephrotic range proteinuria is a hallmark clinical presentation of renal involvement in LCDD.
• Diagnosis relies on characteristic findings from renal biopsy, including specific staining patterns on immunofluorescence and electron microscopy.

Observation:

• A 58-year-old man presented with nephrotic range proteinuria.
• Renal biopsy revealed mesangial matrix expansion, thickened glomerular basement membrane (GBM), and monoclonal kappa light chain staining on immunofluorescence (IF).
• Electron microscopy (EM) showed extensive subendothelial and mesangial dense deposits, confirming LCDD.

Findings:

• The patient was treated with melphalan and prednisolone (MP) therapy for 10 years.
• Serial renal histology evaluations showed resolution of nodular lesions and near-normalization of glomeruli.
• Minimal complications were observed during the extended treatment period.

Implications:

• Long-term melphalan and prednisolone (MP) therapy can be a highly effective treatment for light chain deposition disease (LCDD).
• Sustained treatment over a decade led to significant histological improvement and resolution of renal lesions.
• This case highlights the potential of prolonged chemotherapy in managing LCDD, suggesting a favorable long-term prognosis with consistent therapy.