Waldenstrom macroglobulinaemia, a B-cell lymphoproliferative disorder, characterised by the presence of an IgM monoclonal protein, requires assessment of lymphadenopathy and splenomegaly. In the case of multiple myeloma, the symptoms are classically denoted by the acronym CRAB (hyperCalcaemia, Renal impairment, Anaemia, and Bone lesions) ( Fig. When a monoclonal protein is identified, investigations should be performed to evaluate for associated symptoms. Routine screening with an SPEP (or serum FLC assay) is not indicated in the absence of signs or symptoms of an associated disorder. Indications to order SPEP screening are set out in Table 1 and Fig. Monoclonal protein investigations (SPEP, immunofixation, and serum FLC assay) should be used to identify patients with plasma cell disorders (multiple myeloma being the most common).

When should I test for a monoclonal protein?

Contemporary guidelines do not support routine screening for MGUS, as the diagnosis does not require specific therapy, has been associated with psychological harm to the patient, and is associated with significant healthcare costs Therefore, it is imperative that the decision to pursue monoclonal testing be clinically justified ( Table 1, Fig. MGUS is a precursor to conditions such as multiple myeloma, AL amyloidosis and Waldenstrom macroglobulinaemia, although the majority of patients with MGUS do not develop these conditions. C-reactive protein is elevated (30 mg/L normal 50 years of age, and is twice as common in patients of African ethnicity. Electrolytes, renal and liver function are within normal limits. Her white blood cell (WBC) count is 9 x 10 9/L (normal range 4.5 - 11 x 10 9/L normal WBC count differential), Hb 10 g/dL (normal range 14 - 18 g/dL), mean corpuscular volume 90 fl (normocytic) and platelet count 560 x 10 9/L (normal range 150 - 450 x 10 9/L). Patient 1 is a 67-year-old woman with unexplained normocytic anaemia on routine blood tests. Using a case-based approach, we highlight common misconceptions with monoclonal protein investigations, and suggest a practical framework for diagnostic interpretation. When indicated, a serum protein electrophoresis with immunofixation and serum free light-chain assay should be performed to determine the type and quantity of monoclonal protein. While routine screening in the absence of signs or symptoms of disease is not recommended, testing is indicated in the diagnostic work-up for multiple myeloma and other plasma cell disorders.

Monoclonal proteins are immunoglobulins secreted by identical but abnormal plasma cells that are clones of a parent cell. IVMB ChB, MPH Section of Hematology and Medical Oncology, Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg and Department of Medical Oncology and Hematology, CancerCare Manitoba, Winnipeg Canada IIIMD, MSc Section of Hematology and Medical Oncology, Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg and Department of Medical Oncology and Hematology, CancerCare Manitoba, Winnipeg Canada IIMD, MSc Section of Hematology and Medical Oncology, Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg and Department of Medical Oncology and Hematology, CancerCare Manitoba, Winnipeg Canada IMD Section of Hematology and Medical Oncology, Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg and Department of Medical Oncology and Hematology, CancerCare Manitoba, Winnipeg Canada Laboratory testing in the evaluation of a monoclonal protein: A practical framework for interpretationī L Houston I E Rimmer II R Zarychanski III M Sefte IV

M protein spike causes