AL amyloidosis: Singapore Myeloma Study Group consensus guidelines on diagnosis, treatment and management.

AL amyloidosis is the most common form of systemic amyloidosis. However, the non-specific nature of presenting symptoms requires the need for a heightened clinical suspicion to detect unexplained manifestations in the appropriate clinical setting. Early detection and treatment are crucial as the degree of cardiac involvement emerges as a primary prognostic predictor of survival in a patient with AL amyloidosis. Following the diagnosis of AL amyloidosis with appropriate tissue biopsies, prompt treatment with a bortezomib, cyclophosphamide and dexamethasone-based first-line induction with or without daratumumab should be initiated. The goal of treatment is to achieve the best haematologic response possible, ideally with involved free light chain <20 mg/L, as it offers the best chance of organ function improvement. Treatment should be changed if patients do not achieve a partial response within 2 cycles of treatment or very good partial response after 4 cycles or after autologous stem cell transplant, as achievement of profound and prolonged clonal responses translates to better organ response and long-term outcomes. Early involvement of multidisciplinary subspecialists such as renal physicians, cardiologists, neurologists, and gastroenterologists for optimal maintenance and support of involved organs is recommended for optimal management of patients with AL amyloidosis.

The Singapore Myeloma Study Group Consensus Guidelines for the management of patients with multiple myeloma.

Multiple myeloma (MM) is an incurable plasma cell neoplasm with an incidence of 100 patients per year in Singapore. Major advances have been made in the diagnosis, risk stratification and treatment of MM in the recent past. The reclassification of a subset of patients with smouldering MM, based on high-risk biomarkers, and the development of the revised international staging system are among the key new developments in diagnosis and staging. The use of novel agent-based treatment has resulted in significant improvements in the survival and quality of life of many patients with MM. Determining the optimal use of proteasome inhibitors, immunomodulators and, more recently, monoclonal antibodies is an area of ongoing investigation. In this guideline, we aim to provide an overview of the management of MM, incorporating the latest developments in diagnosis and treatment.

Immunoglobulin G paraprotein cross-reactivity with immunoglobulin M measurement.

We report a case of IgG paraprotein cross-reactivity with IgM measurement in a patient with IgGkappa multiple myeloma and associated IgA and IgM immune paresis. IgM measurements using a Beckman-Coulter Synchron LX IgM reagent initially gave unmeasurably low IgM concentrations (<0.3 g/L) but IgM quantitation using later batches of reagent gave IgM concentrations of 13-42 g/L. Immunofixation confirmed the continued presence of the IgGkappa paraprotein band with suppression of IgA and IgM and analysis on the Behring BN2 and Beckman-Coulter Immage instruments showed IgM concentrations of <0.2 g/L. Immunofixation using the Synchron LX IgM reagent as antiserum confirmed binding of the Synchron LX IgM antiserum to the IgGkappa paraprotein. This case highlights the importance of checking all unexpected immunoglobulin measurements with previous results and immunofixation findings to avoid mistakes.