Light chain deposition disease (LCDD) damages most frequently kidneys, and less frequently other organs. The incidence of LCDD is lower than the incidence of
AL-amyloidosis. Symmetric swelling of both legs was the first sign of
nephrotic syndrome with
renal insufficiency in our female patient. Renal biopsy specimen revealed the diagnosis of LCDD. Bone marrow biopsy contained 40% of plasma cells. Bone survey showed no osteolytic changes. These findings confirmed the diagnosis of
multiple myeloma (MM) Durie Salmon stage IB with LCDD. The patient was initially treated with 4 cycles of VAD (vinkristine, adriamycine,
dexamethasone)
chemotherapy with no response. Followed collection of peripheral haematopoietic stem cells and later high dose
chemotherapy with reduced dose of
melphalan 140 mg/sqm and autologous peripheral haematopoietic stem cells
transplantation.
Melphalan dose was reduced because of
renal insufficiency (serum
creatinine 290 micromol/l) before application of conditioning regimen. High dose
therapy was complicated by with deterioration of renal function,
creatinine increased to 600 micromol/l. Worsening of renal function was most likely caused by nephrotoxicity of
melphalan in
nephrotic syndrome. This has been previously described in patients with
AL-amyloidosis, and
nephrotic syndrome who were treated with high dose
melphalan. This phenomenon was entitled "post conditioning
renal insufficiency".
Hypoalbuminemia hypoproteinemia and reduced intravascular volume and renal damage caused by
amyloid deposits as well as probably, amorphous non-
amyloid deposits of monoclonal
immunoglobulin are likely to have contributed to nephrotoxicity of the high dose of
melphalan. However, worsening of
renal insufficiency was facilitated by the
mucositis-associated
sepsis. Follow-up examination one month after high dose
chemotherapy showed complete remission, that was confirmed by further examinations. In the course of the first year after high dose
chemotherapy renal function gradually improved and
nephrotic syndrome completely disappeared (complete kidney remission).
Proteinuria declined to 2-3 g/24 hours and glomerular filtration slowly improved. Three years after high dose
chemotherapy the patient is still
in complete remission of
multiple myeloma and free of
nephrotic syndrome, with slightly increased
creatinine (160 micromol/l) that, nevertheless, has had an improving tendency over last 3 years. The present case study illustrates accomplishment of complete haematological remission with high dose
chemotherapy followed by autologous haematopoietic stem cells
transplantation despite complete resistance of the disease to the standard
chemotherapy VAD in a patient with MM and LCDD. We draw the reader's attention to the possibility of nephrotoxic effects of high dose
melphalan (post conditioning
renal insufficiency) in patients with
nephrotic syndrome caused by light chain deposits as AL-
amyloid or amorphous light chains deposits (LCDD)and we document the importance of plasma free light chain detection.