Multiple myeloma is a disease of the plasma cells of the bone marrow, resulting in the proliferation and release of the monoclonal protein, which further causes end-organ damage. We report an unusual presentation of multiple myeloma, thereby insisting on the need for the treating physician to be aware of the various presentations that can be encountered in regular practice. It is often difficult to diagnose, and the diagnosis is usually made at a late stage of the disease. Even though uncurable, with recent advances, a proper regimen, newer chemotherapeutic agents, and stem cell transplantation, the disease can be brought into remission.

Multiple myeloma (MM) is a hematologic malignancy characterized by the clonal proliferation of plasma cells in the bone marrow. It commonly presents with bone pain, anemia, renal failure, and hypercalcemia. Pleural effusion in MM usually has multiple causes, but it is rare for the effusion to be due to myelomatous deposition of the pleura. Here, we present a rare case in which the patient presented to the outpatient department with a dry cough, breathlessness, and generalized weakness. The patient was diagnosed with MM with myelomatous pleural effusion (MPE), highlighting the importance of considering MM as a differential diagnosis in patients with atypical presentations. MPE indicates a poor prognosis, and early consideration of MPE can lead to an earlier diagnosis and a more effective treatment of MM.

BACKGROUND: Monoclonal gammopathies occurs in patients with malignant diseases of plasma cells and lymphocytes and in few benign conditions. The objective of this study was to assess the precision, accuracy and confirmation of monoclonal gammopathies on serum protein electrophoresis (SPE) and the clinical relevance of detection and characterization of M component.
METHODS: All samples received for serum electrophoresis in the last 3 years were analysed for data on M band positivity and correlating it with clinical profile of the patients. Immunofixation (IFE), Immunoelectrophoresis (IEP) and IgG, IgM estimation were carried out in few cases. The follow up of cases was done by serial monitoring of SPE and β2 microglobulin levels.
RESULTS: 1155 samples were received during the 3 years period. 282 (24.4%) samples were positive for M component on SPE. Of these, 239 (84.8%) patients had M spike in λ region and 43 patients had M spike in β region. The mean load of the M protein band in the λ region was 37.8% and in β region was 35.8%. IgG with κ chain was seen in 40%, IgG with λ chain was seen in 50%, 5% patients each had IgM with κ and IgA with λ light chain. 246 samples (96.5%) had high levels of β2 microglobulin. Of the 116 cases of multiple myeloma, IgG levels was more commonly raised (5%) as compared to IgA (6.9%) and IgM (5.2%).
CONCLUSIONS: It is recommended that SPE should be performed in patients having unexplained weakness, anaemia, back pain, osteoporosis, osteolytic lesions, fractures, renal insufficiency or recurrent infections.