Large vessel (Takayasu's) arteritis in a patient with myelodysplastic syndrome: is there a common pathogenesis?

Autoimmune phenomena may complicate the course of myelodysplastic syndromes (MDS) but large vessel arteritis is a rare event. We report a case of large vessel arteritis in a patient with MDS. A 62-year-old male presented with thrombocytopenia and was diagnosed with low-risk MDS, (<5% blasts in his bone marrow and a normal karyotype). Shortly thereafter he developed large vessel (Takayasu's) arteritis (TA) that responded well to oral corticosteroid and methotrexate therapy. Ten months later the MDS transformed into acute myeloid leukemia (AML). After a successful induction course with cytarabine and daunorubicin he underwent allogeneic transplantation from a matched unrelated donor with reduced-intensity conditioning. The transplantation was complicated by systemic cytomegalovirus (CMV) disease and he died 6 weeks post transplantation. Takayasu's arteritis is an uncommon form of vasculitis affecting primarily young women and is atypical for elderly males. Though autoimmune manifestations in MDS occur in 10%-18.5% of patients, usually large vessels are spared. In MDS, activated T cells are thought to mediate bone marrow failure via overproduction of proinflammatory cytokines that cause stem cell apoptosis. These T cells may also mediate the autoimmune phenomena in MDS. The prognostic significance of autoimmunity in the course of MDS is not yet determined. Some reports suggest worse prognosis. The case illustrates a possible association between MDS and large vessel vasculitis and suggests a possible relationship between the presence of autoimmune syndromes and the outcome of patients with MDS.