Abstract | BACKGROUND: METHODS: We report a novel finding in two cases of heavy- and light-chain amyloidosis (AHL) in which monoclonal Ig but not serum amyloid P (SAP), apolipoprotein E ( ApoE) or amyloid bulk in the kidney regressed after successful therapy. RESULTS: In the pre-treatment renal biopsies, the amyloid deposits stained for one heavy and one light chains ( IgG + λ in one case and IgA + κ in one case). Laser microdissection followed by mass spectrometry (LMD/MS) in both cases showed abundant spectra for Ig heavy and light chains, SAP and ApoE. Both patients achieved a hematologic response with disappearance of the monoclonal protein from serum and urine and normalization of serum-free light chain ratio, but renal response occurred in only one patient. Repeat kidney biopsies showed persistence of fibrillar amyloid deposits, but regression of Ig from the amyloid deposits based on immunofluorescence. LMD/MS on the repeat biopsy performed in one case also showed disappearance of Ig but not SAP or ApoE. CONCLUSIONS: Our finding suggests that effective chemotherapy and/or ASCT in some patients with AHL not only eliminates the circulating pathogenic monoclonal Ig but also the Ig component of amyloid deposits, which may translate into renal response. This, however, may not lead to regression of amyloid deposits themselves. The latter may require more time or addition of therapeutic agents that target amyloid-associated proteins such as SAP, which are not commercially available.
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Authors | Sami Safadi, Ahmed Saad, Patrick S Quint, Sanjeev Sethi, Nelson Leung, Paul Kurtin, Samih H Nasr |
Journal | Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association
(Nephrol Dial Transplant)
Vol. 30
Issue 7
Pg. 1151-5
(Jul 2015)
ISSN: 1460-2385 [Electronic] England |
PMID | 25796445
(Publication Type: Case Reports, Journal Article)
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Copyright | © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved. |
Chemical References |
- Immunoglobulin Heavy Chains
- Immunoglobulin Light Chains
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Topics |
- Amyloidosis
(metabolism, pathology, therapy)
- Fluorescent Antibody Technique
- Humans
- Immunoglobulin Heavy Chains
(metabolism)
- Immunoglobulin Light Chains
(metabolism)
- Laser Capture Microdissection
- Male
- Mass Spectrometry
- Middle Aged
- Plaque, Amyloid
(metabolism, pathology, therapy)
- Stem Cell Transplantation
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