A 52-year-old man presented to the emergency department with fevers and chills and was admitted with a diagnosis of pneumonia. CT to exclude pulmonary embolus showed diffuse osseous lytic lesions, and he was also found to have anemia and an IgG kappa monoclonal protein of 55·8 g/L on protein electrophoresis (a single band).

Image of bone marrow aspirate is attached. *This case is from Docplexus Editorial Team for educative purpose only Source: The Lancet