A long-survival case of systemic AL amyloidosis with nephrotic syndrome

A 49-year-old Japanese female was initially diagnosed as having monoclonal gammopathy of undetermined significance in June 1993 (IgG lambda: 3,120 mg/dl). Four years later, she developed AL amyloidosis complicated by nephrotic syndrome and renal failure. Before receiving 5 courses of MP therapy (melphalan plus prednisolone), her serum IgG level had decreased in accordance with the appearance of nephrotic syndrome, which led to the leakage of serum immunoglobulin into the urine. After the discontinuation of the MP therapy, hypogammaglobulinemia has been kept over 24 months, though she still shows a leakage of 4-5 g/day of serum protein, including IgG into the urine. There were no signs of the progression of amyloidosis or renal failure, resulting in a good clinical performance status. Hypogammaglobulinemia due to nephrotic syndrome may have prevented the progression of AL amyloidosis in this case.