Waldenström’s macroglobulinemia is a condition consisting of bone marrow involvement from a lymphoplasmacytic lymphoma accompanied by a serum IgM paraprotein. Waldenström’s is occasionally associated with cryoglobulinemia, resulting in cold-induced precipitation of immunoglobulins. Immunoglobulins can also accumulate in plasmacytoid cells, resulting in inclusion bodies and giving the characteristic appearance of Mott cells and Russell bodies. We present a visually striking case of Waldenström’s macroglobulinemia with prominent inclusion bodies secondary to cryoglobulinemia.
A 44 year old woman presented with lethargy, weakness and coryzal symptoms with associated anaemia (Hb 64g/L) and thrombocytopenia (platelet count 60x109/L). Blood film demonstrated a leukoerythroblastic film with red cell agglutination, cryoglobulins, and lymphocytosis with atypical forms seen. An IgM and IgG paraprotein was detected at 8.3g/L and 2.8g/L respectively. There was no lymphadenopathy nor splenomegaly clinically or on CT imaging. A bone marrow biopsy was performed which demonstrated a markedly hypercellular marrow with a mature lymphocyte infiltrate with prominent Mott cells seen in the aspirate. Similarly, in the trephine there was a striking diffuse infiltrate of plasma cells which contained large, amorphous “Russell body” like inclusion material, and stained positive on CD138 and kappa immunoperoxidase stains. There was also once again a diffuse lymphocyte infiltrate throughout the bone marrow which was positive for CD20, CD45, weak CD23 and SOX11 stains. Flow cytometry on bone marrow aspirate demonstrated a monoclonal B cell population. She was commenced on Rituximab-Bendamustine chemotherapy without any significant complications after three cycles other than mild liver function test derangement. Her anaemia has resolved, with reduction in paraprotein but persistent thrombocytopenia secondary to chemotherapy affect.
Although not uncommonly seen in Waldenström’s macroglobulinemia, this case highlights a particularly prominent case of plasmacytoid cells with inclusion bodies, likely related to presence of cryoglobulinemia.