Italian 
English CASI CLINICI – Case Reports
Volume:
Biochimica Clinica 2020; 44(2) E11-E15
Pubblicato on-line:
Gennaio 15, 2020
DOI:
10.19186/BC_2020.003
I marcatori di clonalità per la diagnosi e la valutazione della risposta alla terapia nell’amiloidosi da catene leggere: il ruolo del laboratorio
Clonal biomarkers for diagnosis and response to treatment assessment in light chain amyloidosis: the role of the laboratory
AUTORI
Tiziana Bosoni2, Laura Pirolini2, Riccardo Albertini2, Giovanni Palladini1
1Centro per lo Studio e la Cura delle Amiloidosi Sistemiche, Laboratorio Biochimica - Biotecnologie e Diagnostica avanzata, Fondazione IRCCS Policlinico San Matteo, Dipartimento di Medicina Molecolare, Università di Pavia
2Servizio di Analisi Chimico Cliniche, Fondazione IRCCS Policlinico San Matteo, Pavia
ABSTRACT
Clonal biomarkers for diagnosis and response to treatment assessment in light chain amyloidosis: the role of the laboratory.
Serum monoclonal components, Bence-Jones proteinuria (PBJ) and free light chains (FLC) are clonal biomarkers for diagnosis and response assessment in light chain (AL) amyloidosis. Two clinical reports are presented here to illustrate the utility of these biomarkers. The first case is a patient with AL κappa renal amyloidosis. Serum and urine immunofixation were negative and the FLC ratio was abnormal. Immunoelectron microscopy on tissue biopsy was negative. Amyloid typing was achieved by mass spectrometry on fat pad aspirate. The second case is a patient with AL cardiac amyloidosis with PBJ lambda and low concentration of amyloidogenic FLC (32 mg/L). Urine capillary electrophoresis was used to assess response to treatment. The progressive reduction of PBJ after treatment was accompanied by reduction of NT-proBNP and improvement of clinical conditions. Clonal biomarkers are irreplaceable tools in management of AL amyloidosis. There is a need for more sensitive techniques for identification of monoclonal FLC on serum and urine.