The Evaluation of Amyloidosis Cases with Renal Involvement: A Single-Center Experience

OBJECTIVE: Amyloidosis is a chronic disease associated with proteinuria and can progress
to renal failure. The diagnosis and treatment of the underlying cause is therefore important. In this
study at a university hospital, the diagnosis of amyloidosis patients with renal biopsies was evaluated
retrospectively.

MATERIAL and METHODS: 69 (42 males, 27 females, mean age: 51.7 ± 14.8 years) patients
were diagnosed with amyloidosis with renal biopsy. Indications for biopsy was nephrotic syndrome
in 42 patients (60.9%), nephritic syndrome in 27 (39.1%) and renal dysfunction with proteinuria in 31
(44.9%).

RESULTS: The most common causes of secondary amyloidosis were Familial Mediterranean Fever
in 17 of the 62 patients, chronic inflammatory diseases in 17 patients and chronic infection in 13
patients. No cause was determined in 12 patients. Multiple myeloma was present in 5 patients with
primary amyloidosis. At the time of diagnosis with amyloidosis, 19 patients were stage 1, 15 stage 2, 5
stage 3A, 12 stage 3B, 10 stage 4 and 8 stage 5. The baseline hemoglobin, serum albumin, creatinine,
sodium, potassium, calcium, phosphorus, AST, ALT, PTH, SAA, CRP levels, average daily urinary
protein excretion and baseline GFR values were not significantly different in primary and secondary
amyloidosis patients. The treatment was medical in 62.3% of the patients, dialysis in 31.9% and renal
transplantation in 5.8%.

CONCLUSION: The reliability of renal biopsy in the diagnosis of amyloidosis is high. However, genetic studies for the diagnosis of idiopathic
cases and special histological staining methods should be considered.