How to manage primary amyloidosis.

Immunoglobulin light chain amyloidosis is a protein deposition disorder where the precursor protein represents a monoclonal immunoglobulin light or heavy chain. Deposition in viscera results in restrictive cardiomyopathy, nephrotic range proteinuria, demyelinating peripheral neuropathy, hepatomegaly and malabsorption syndrome. Diagnosis requires biopsy with Congo red staining. Invasive biopsies are not required generally. It is essential that after a histologic diagnosis is obtained, the tissue is validated to have an immunoglobulin light chain composition so patients are spared unnecessary chemotherapy. The disease prognosis and patient monitoring are linked to serialized measurement of cardiac biomarkers and immunoglobulin-free light chains. Most patients require cytotoxic chemotherapy. For some patients, this therapy involves stem cell collection and myeloablative chemotherapy; for others, chemotherapy includes an alkylator and a corticosteroid; and for some, it involves addition of a novel agent in the form of an immunomodulatory drug or a proteasome inhibitor. Delays in diagnosis continue to be an obstacle to initiating effective therapy. Early mortality rates remain high. Effective chemotherapy can result in reversal of organ dysfunction and recovery. Reductions in light chain production translate to improved survival.