Concurrent ankylosing spondylitis and myelodysplastic syndrome: A case report

Ankylosing spondylitis (AS) is an autoimmune disease characterized by sacroiliitis and spondylitis, with a few hematological abnormalities. Myelodysplastic syndromes (MDS) are a heterogeneous group of hematopoietic stem cell disorders with frequent autoimmune phenomena. The relationship between AS and MDS remains unknown. We describe a rare case of concurrent AS and MDS. An 18-year-old man with low back pain and anemia was diagnosed with AS; however, the cause of anemia could not be determined by the first bone marrow examination. He recovered from anemia and the symptoms of AS resolved after treatment with etanercept, glucocorticoid, and blood transfusion, but he developed pancytopenia with an increased myeloblast count (from 2.5% to 9%). Chromosome analysis revealed del(7q) and trisomy 8. Refractory anemia with excess of blasts-1 (RAEB-1)/MDS was confirmed by repeating the bone marrow examination. He became blood transfusion-dependent and received decitabine-based chemotherapy but eventually died. We suspect that AS may be an early autoimmune phenomenon related to MDS. However, a condition of coexistence cannot be excluded.