IgE multiple myeloma: detection and follow-up

OBJECTIVES: We report a new case of immunoglobulin E multiple myeloma (IgE), a very rare isotype that accounts for <0.1% of cases of this monoclonal gammopathy. To ensure the adequate detection, quantification and identification of the monoclonal component, it is crucial that protein assays are performed. We provide some clues related to clinical laboratory results, which will facilitate an adequate management of the disease. CASE PRESENTATION: A 45-year-old patient with a five-week history of pain at the level of the elbow, who was diagnosed with IgE-Kappa multiple myeloma based on laboratory, radiological, and bone marrow findings. The patient received induction chemotherapy prior to hematopoietic stem-cell transplantation and is currently on follow-up. CONCLUSIONS: Protein assays performed in the clinical laboratory, including protein electrophoresis and immunofixation, allowed for the detection of an IgE-Kappa monoclonal component prior to the appearance of the typical CRAB symptoms (hypercalcemia, renal involvement, anemia, and bone pain) of multiple myeloma (MM). The detection of IgE-Kappa facilitated early diagnosis and management.