Significance of urinary albumin excretion inpatients with cast nephropathy .

Ryo Nakagawa,Noriko Hayami,Hiroki Mizuno,Masahiro Kawada,Eiko Hasegawa,Akinari Sekine,Rikako Hiramatsu,Tatsuya Suwabe,Junichi Hoshino,Keiichi Sumida,Yoshifumi Ubara,Takeshi Fujii,Masayuki Yamanouchi,Kenmei Takaichi,Aya Imafuku,Kenichi Ohashi,Atsushi Wake,Naoki Sawa

doi:10.5414/cn109630

Abstract

Background: This study was performed to determine whether the urinary albumin excretion rate (%UAE) could distinguish myeloma cast nephropathy (MCN) without glomerular amyloid deposition from MCN with glomerular amyloid deposition. Materials and methods: We retrospectively reviewed clinicopathological data on 16 patients with MCN diagnosed by renal biopsy at Toranomon Hospital from 2004 to 2014. Results: A total of 10 patients had pure MCN without glomerular amyloid deposition (group 1), and 6 patients had MCN with glomerular amyloid deposition (group 2). In all 10 patients from group 1, the underlying disease was multiple myeloma (MM), while 4 patients had MM, and 2 patients had lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) in group 2. Total protein did not show a significant difference between the two groups, but serum albumin was significantly higher in group 1 than group 2 (p = 0.0101). Serum-adjusted calcium did not show a significant difference between the groups, while serum creatinine (Cre) was significantly higher in group 1 than group 2 (p = 0.0343). Although urinary protein excretion did not differ significantly between the groups, the %UAE was significantly lower in group 1 than group 2 (p = 0.00198). In group 2, 3 of the 4 patients with MM died within 15 months of diagnosis, but the 2 patients with LPL/WM are alive after 32 months. In group 1, only 1 patient died (of unknown causes) within 15 months after diagnosis. Conclusion: In patients with MCN, %UAE may be a useful marker for the detection of coexistence of glomerular lesions, such as amyloidosis, which are associated with a poor outcome.

Highlights

Renal biopsy is considered to be important for the diagnosis of renal involvement in patients with multiple myeloma (MM) because of the therapeutic and prognostic implications
While myeloma cast nephropathy (MCN) is the most common kidney disease associated with MM, it has been reported to occur in patients with lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) [5, 6]
Patients were excluded if they had monoclonal immunoglobulin deposition disease (MIDD) including light chain deposition disease (LCDD), light and heavy chain deposition disease (LHCDD) and heavy chain deposition disease (HCDD), or if they had primary light chain (AL) and heavy chain (AH) amyloidosis, which did not fit the diagnostic criteria for MM [7] or LPL/WM [8]. 16 patients with a diagnosis of MCN were analyzed retrospectively

Summary

Introduction

Renal biopsy is considered to be important for the diagnosis of renal involvement in patients with multiple myeloma (MM) because of the therapeutic and prognostic implications. Korbet and Schwartz [1] reviewed renal biopsy data on renal disease in MM patients, revealing that 40 – 63% had myeloma cast nephropathy (MCN), 19 – 26% had light chain deposition disease (LCDD), 7 – 30% had amyloidosis, and less than 1% had cryoglobulinemic renal disease [1, 2]. According to these studies, renal pathology in patients with MM shows a single pattern.

Materials and methods

63 M Anasarca

Discussion

Findings

Limitation