Paolo Milani MD, PhD , Giuseppe Damiano Sanna MD, PhD , Claudia Bellofiore MD , Mario Nuvolone MD, PhD , Marco Basset MD, PhD , Roberta Mussinelli MD, PhD , Giulia Mazzini BS , Martina Nanci MD , Martina Ciardo MD , Serena Caminito BS , Matin Ghazi Esfahani MS , Mohammadjavad Sadrzadeh MS , Alessandro Fogliani MD , Francesca Benigna MD , Gianluigi Guida MD , Francesco Salinaro MD, PhD , Tiziana Bosoni BS , Alessandra Barassi MD , Andrea Foli MD , Riccardo Albertini MD , Giovanni Palladini MD, PhD
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引用次数: 0
Abstract
Background
Detection of monoclonal components (MCs) using serum and urine immunofixation (IFE) and free light chain measurement is a critical early step in diagnosing cardiac amyloidosis. Patients with MCs are referred for biopsy-based diagnostic work-up. New reference ranges for the free light chain ratio (FLCR), adjusted for age and estimated glomerular filtration rate, have been proposed.
Objectives
The aim of this study was to compare the diagnostic performance of the new vs the conventional FLCR in patients with light chain (AL) amyloidosis and wild-type transthyretin (ATTRwt) amyloidosis.
Methods
The analysis included 1,705 patients with AL amyloidosis and 675 with ATTRwt amyloidosis.
Results
In the AL cohort, 44 patients (3%) had negative results on serum and urine IFE at diagnosis. Among these, 13 patients had normal conventional FLCRs and 15 had normal new FLCRs, with no significant difference in diagnostic sensitivity (70.4% [95% CI: 55.8%-82.5%] vs 65.9% [95% CI: 50.0%-79.5%]; P = 0.82). Overall diagnostic sensitivity for MC detection was similar between the new and conventional FLCRs (99.2% vs 99.1%). Among patients with ATTRwt amyloidosis and negative serum and urine IFE results, 156 (26.5%) had abnormal FLCRs using the conventional cutoff, compared with only 12 (2%) using the new FLCR. At hematologic response assessment in AL amyloidosis, concordance in the definition of complete response between the 2 FLCR methods was 94.9% (95% CI: 93.4%-95.9%).
Conclusions
The new FLCR demonstrates equivalent diagnostic sensitivity in AL amyloidosis and can be integrated into complete response criteria. In patients with suspected ATTRwt amyloidosis, it significantly reduces the proportion of FLCR-only abnormalities, thereby limiting the need for biopsy confirmation.
期刊介绍:
JACC: CardioOncology is a specialized journal that belongs to the esteemed Journal of the American College of Cardiology (JACC) family. Its purpose is to enhance cardiovascular care for cancer patients by publishing high-quality, innovative scientific research and sharing evidence-based knowledge.
The journal aims to revolutionize the field of cardio-oncology and actively involve and educate professionals in both cardiovascular and oncology fields. It covers a wide range of topics including pre-clinical, translational, and clinical research, as well as best practices in cardio-oncology. Key areas of focus include understanding disease mechanisms, utilizing in vitro and in vivo models, exploring novel and traditional therapeutics (across Phase I-IV trials), studying epidemiology, employing precision medicine, and investigating primary and secondary prevention.
Amyloidosis, cardiovascular risk factors, heart failure, and vascular disease are some examples of the disease states that are of particular interest to the journal. However, it welcomes research on other relevant conditions as well.