Light and heavy chain deposition disease with focal amyloid deposition diagnosed with mass spectrometry: a case report

BMC Nephrology

Case Report

Yusuke Mochizuki¹  Nagaaki Katoh¹  Yoshiki Sekijima²  Masanori Ito³  Yuki Matsui³  Kenji Kasuno⁴  Masayuki Iwano⁴  Yuki Shimamoto⁴  Naoki Takahashi⁴  Hironobu Naiki⁵  Masahide Yazaki⁶  Fuyuki Kametani⁷ 

[1] Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, Matsumoto, Nagano, Japan;Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, Matsumoto, Nagano, Japan;Institute for Biomedical Sciences, Shinshu University, Matsumoto, Nagano, Japan;Department of Nephrology and Urology, Japanese Red Cross Fukui Hospital, Fukui, Japan;Department of Nephrology, Faculty of Medical Sciences, University of Fukui, 23-3 Matsuokashimoaizuki Eiheiji-Cho, Yoshida-Gun, Fukui, Japan;Department of Pathology, University of Fukui, Fukui, Japan;Institute for Biomedical Sciences, Shinshu University, Matsumoto, Nagano, Japan;Clinical Laboratory Sciences Division, Shinshu University Graduate School of Medicine, Matsumoto, Nagano, Japan;Tokyo Metropolitan Institute of Medical Science, Setagaya-Ku, Tokyo, Japan;

关键词: Light and heavy chain deposition disease;    Amyloidosis;    Mass spectrometry;    Congo red;    Birefringence;    Nephrotic syndrome;   

DOI  :  10.1186/s12882-023-03207-0

 received in 2022-12-30, accepted in 2023-05-18,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundLight and heavy chain deposition disease (LHCDD) is a rare condition characterised by the deposition of immunoglobulin components in the kidneys. Similarly, Amyloidosis is also caused by the deposition of light chain and/or heavy chain components of immunoglobulins which are folded into amyloid fibrils characterised by Congophilic deposits that exhibit apple-green birefringence under polarised light. Only a handful of reports describing LHCDD with amyloid fibril deposition have been previously published, however, none have characterized the composition of the deposited immunoglobulin components via mass spectrometry.Case presentationWe report a case of a 79-year-old Japanese woman with nephrotic syndrome. Bone marrow aspiration revealed a slight proliferation of plasma cells (under 10%). Immunofluorescence assessment of renal biopsy showed amyloid-like deposits in the glomerulus that were positive for IgA and kappa. Further, the Congo red staining of the deposits was faintly positive, and only a slight birefringence was detected. Electron microscopy confirmed fine fibrillar structures and non-amyloid deposits. Finally, mass spectrometry revealed that the deposits were composed of abundant amounts of light chain with small amounts of heavy chain. Therefore, the patient was diagnosed with LHCDD and focal amyloid deposition. Chemotherapy was subsequently initiated, which resulted in haematological and renal response. Under polarised light, faint birefringence with Congo red staining and periodic acid-methenamine silver positivity indicated that the deposits were mostly non-amyloid fibrils with a small component of amyloid fibrils. Generally, the diagnosis of heavy- and light-chain amyloidosis is defined by greater heavy chain deposition compared to the light chain. However, in our case, contrary to the definition, the light-chain deposition was far greater than that of the heavy-chain.ConclusionsThis is the first case of LHCDD with focal amyloid deposition diagnosed by analysing the glomerular deposits by mass spectrometry.

【 授权许可】

CC BY   
© The Author(s) 2023

【 图 表 】

Fig. 4

40517_2023_252_Article_IEq135.gif

Fig. 2

40517_2023_252_Article_IEq115.gif

40517_2023_252_Article_IEq97.gif

Fig. 2