Un caso di amiloidosi sistemica AL apparentemente senza clone correlato: ruolo della diagnostica avanzata di laboratorio
A patient with systemic AL amyloidosis apparently without an underlying clone: the role of advanced laboratory diagnostic evaluations

AUTORI

ABSTRACT

A patient with systemic AL amyloidosis apparently without an underlying clone: the role of advanced laboratory diagnostic evaluations

Acquired systemic immunoglobulin light chain (AL) amyloidosis invariably occurs in the context of a monoclonal gammopathy. The underlying clone is the source of aggregation-prone circulating light chains which misfold and deposit in target tissues, leading to potentially fatal (multi)organ dysfunction. Demonstrating the underlying clone is mandatory to confirm the diagnosis, justify anti-clonal therapy, and monitor hematologic response to treatment and potential relapse. The combination of serum/urine protein electrophoresis with immunofixation and serum free light chain measurements detects an M protein in the vast majority of cases at diagnosis. Yet, rare cases with particularly low clonal burden, conventional M protein and bone marrow studies are negative, requiring the use of advanced diagnostic evaluations with increased sensitivity. Here, we present the case of a patient with suspected AL amyloidosis and negative conventional M protein and bone marrow studies, where high-resolution electrophoresis/immunofixation, next-generation flow cytometry and next-generation sequencing promptly detected the disease-causing clone.

BIBLIOGRAFIA

Bibliografia
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