Refractory anaemia with ringed sideroblasts concurrent with multiple myeloma--a brief review of the recent literature.

The report describes a patient in whom myelodysplastic syndrome and multiple myeloma (MM) were simultaneously present. This patient manifested an IgA-lambda type of MM concurrent with a refractory anaemia with ringed sideroblasts (RARS) without prior therapy. His bicytopenia could not be improved by vitamin B6 regardless of a reduced serum vitamin B6 concentration. A review of the literature suggests that myelodysplastic syndrome (MDS), chronic neutrophilic leukaemia (CNL) and idiopathic myelofibrosis (IMF) are the most frequent disorders associated with MM. The IgA type seems to be associated more commonly with these disorders. The mechanisms responsible for the development of plasma cell proliferation are diverse; the neoplastic transformation of a common progenitor, the involvement of the lymphoplasmacytic system and/or chronic reticuloendothelial stimulation may play a role in the occurrence of such hybrid haematological disorders.