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In around 5-7% of patients, AL amyloidosis is associated with IgM paraprotein [1131][1132][1133][1134] and in over half of cases the condition is secondary to non-Hodgkin lymphoma [1135]. Although IgM AL amyloidosis shares a number of characteristics with non-IgM AL amyloidosis [1136][1137], it represents a distinct clinical entity [1137]. IgM AL amyloidosis is characterised by a higher incidence of lymph node and neuropathic involvement, and less severe cardiac dysfunction when compared to non-IgM AL amyloidosis [1132][1135]. Generally, IgM AL amyloidosis patients have lower levels of iFLCs than non-IgM patients (median 63 mg/L vs. 182 mg/L), which are more commonly of the κ type (42% vs. 23%) [1131][1132][1135].