English 
Italian Utilità del saggio Hevylite nella gestione clinica di una paziente affetta da amiloidosi AL con gammopatia biclonale
AUTHORS
1Centro per lo Studio e la Cura delle Amiloidosi Sistemiche, Fondazione IRCCS Policlinico San Matteo, Pavia e Dipartimento di Medicina Molecolare, Università degli Studi di Pavia
2Laboratorio Analisi-Chimico-Cliniche, Fondazione IRCCS Policlinico San Matteo, Pavia
Questo lavoro è stato in parte presentato al 46° Congresso Nazionale SIBioC, 13-15 Ottobre 2014, Roma, all'interno della Sessione "Casi clinici indimenticabili: il contributo della Medicina di Laboratorio".
ABSTRACT
Usefulness of the Hevylite assay in the management of a patient with AL amyloidosis and biclonal gammopathy
Patients with AL amyloidosis often have small monoclonal components (MCs) difficult to quantify by densitometry. IgA are the most problematic, due to anodic migration and possible masking under proteins migrating in β zone. We evaluated the usefulness of the Hevylite assay (Binding Site, Birmingham UK), at diagnosis and during follow-up, in a patient with AL amyloidosis and biclonal gammopathy. At diagnosis serum immunofixation identified an IgGλ and an IgAλ band (the last one not reliably quantifiable in capillary electrophoresis). The κ serum free light chain (FLC) concentration was 4.94 mg/L and λ 26 mg/L (κ/λ ratio 0.19). The Hevylite test showed both IgGλ and IgAλ above the reference limits, with abnormal κ/λ ratios. After treatment, a 27% decrease in IgGλ and a 56% decrease in IgAλ concentration were documented by Hevylite, which was the only mean to quantify the monoclonal components in this patient.