Response of autoimmune and inflammatory disorders in myelodysplastic syndromes to 5-azacytidine: report of two cases and literature review.

Paraneoplastic autoimmune and inflammatory disorders are often associated with myelodysplastic syndromes (MDS). The etiopathogenesis of MDS-associated autoimmune and inflammatory disorders is still unclear and treatment options are limited. Patients with MDS are at high risk of infections, which can be increased by the use of steroids. In the present study, we report on two patients with MDS-related autoimmune and inflammatory disorders who were in remission and reduced the steroid dose with 5-azacytidine treatment. The first case was a 67-year-old patient diagnosed with MDS and the whole-body erythroderma was the chief complaint. When the patient was treated with decitabine, steroid treatment was needed to control the erythroderma. When we changed decitabine to 5-azacytidine, both his erythroderma and his dependency on the steroid treatment were resolved. The second patient was a 68-year-old man with MDS who presented with Sweet's syndrome. Sweet's syndrome was completely treated after the first cycle of 5-azacytidine. In addition, Sweet's syndrome can occur as an adverse reaction of 5-azacitidine, so we illustrate that it is important to distinguish whether Sweet's syndrome is MDS-related skin disorders or 5-azacitidine-related skin side-effects.