[Renal involvement in amyloidosis and sarcoidosis]

Amyloidosis is a rare disease characterized by extracellular deposition of fibrils. Among the most common forms of systemic amyloidosis with renal involvement are AL-amyloidosis based on plasma cell dyscrasia and AA-amyloidosis in chronic inflammatory diseases. Depending on the affected renal compartment, the clinical appearance of renal amyloidosis varies. The pattern of renal amyloid deposition can be glomerular, interstitial, tubular or even vascular. Renal amyloid deposits are detected by renal biopsy. Patients with glomerular deposits typically show severe nephrotic syndrome with volume overload. Patients with predominantly tubulo-interstitial or vascular deposits typically exhibit lower proteinuria and progressive renal impairment. Treatment strategies for renal amyloidosis are primarily based on the treatment of the underlying disease including chemotherapy or stem cell transplantation in AL-amyloidosis or treatment of chronic inflammatory diseases in AA-amyloidosis. Granulomatous interstitial nephritis is the most common renal lesion occurring in sarcoidosis. Therapy of granulomatous interstitial nephritis is mainly based on the use of glucocorticoids.