[Morphological diagnosis of childhood bone marrow failure syndromes].

In 2008, the World Health Organization proposed a provisional entity of childhood myelodysplastic syndrome (MDS) without a blasts increase, which was referred to as the refractory cytopenia of childhood (RCC). We performed a central review of bone marrow morphology in 252 children with acquired bone marrow failure syndromes to clarify the clinical relevance of the RCC. The RCC was divided two categories, namely, RCC without multilineage dysplasia (MLD) and RCC with MLD, which is similar to MDS with MLD in adult MDS. Furthermore, the clinical outcomes were investigated for cases diagnosed with aplastic anemia, RCC without MLD, and RCC with MLD. The response rates to immunosuppressive therapy and the incidence of the development of the new chromosomal aberration did not significantly differ among the three groups. The RCC with MLD can be adopted in childhood MDS since children with this condition exhibited a frequent chromosomal aberration at the time of diagnosis and a high frequency of secondary graft failure after a hematopoietic cell transplantation.