IgE multiple myeloma: detection and follow-up

Abstract

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.

Keywords: immunoglobulin E; multiple myeloma; proteinogram.

Figure 1:

Serum protein test of the patient. (A) Serum proteinogram (Capillarys-2^® Sebia) demonstrating a peak that corresponds to the MC in the γ fraction. (B) Serum immunofixation (Hydragel IF, Hidrasys Sebia^®) demonstrating the IgE-Kappa MC (bands corresponding to the regions of anti-igE and anti-CLL Kappa antisera).

Figure 2:

Progress of the protein test of the patient. (A) Progress of the serum proteinogram of the patient: at diagnosis, with the VRD treatment, pre-apheresis and post-APSCT. The monoclonal peak in the γ fraction progressively decreases. (B) Serum immunofixation. The IgE-Kappa MC is observed at diagnosis and disappears after transplantation. (C) Progress of serum IgE levels and Kappa/Lambda ration. The initial red cross indicates diagnosis, each blue arrow represents a VRD cycle, whereas the yellow arrow indicates the APSCT. A decrease in serum IgE and CLL-Kappa is observed.