Systemic diseases in myelodysplastic syndromes.

Myelodysplastic syndromes (MDS) are characterized by quantitative and functional involvement of myeloid lineages. Yet, systemic manifestations, suggestive of a lymphocytic involvement, have been described in MDS. We review here biological and clinical data concerning the associations between MDS and immunological disorders. Biological auto-immune markers are in fact rare in MDS, and especially encountered in the chronic myelomonocytic leukemia subgroup. Only a few systemic diseases seem to be frequently associated with MDS: seronegative arthritis, cutaneous vasculitis, and relapsing polychondritis. These diseases are probably not entirely auto-immune, and the signification of their association with an MDS remains nuclear. About 30% of relapsing polychondritis are associated with MDS. Conversely, 0.6% of MDS are associated with a relapsing polychondritis. These associations are mainly encountered in men suffering from a refractory anemia (with or without excess of blasts). The main cytogenetic abnormalities are monosomy 7, presence of a ring chromosome, and monosomy 16.