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Updated: Aug 22, 2026
Use of Hematopoietic Stem Cell Transplantation to Assess the Origin of Myelodysplastic Syndrome
Published on: October 3, 2018
Natural history of moderate aplastic anemia in children
Scott C Howard1, Paula E Naidu, X Joan Hu
1Department of Hematology-Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA. scott.howard@stjude.org
Background:
Moderate aplastic anemia (MAA) in children is a rare, idiopathic condition of bone marrow insufficiency that can resolve spontaneously, persist for months or years, or progress to severe aplastic anemia (SAA). We evaluated the rate of progression to SAA.
Methods:
We reviewed the records of 136 children referred for evaluation of bone marrow failure from 1978 to 2002 at St. Jude Children's Research Hospital. MAA was defined by a hypocellular bone marrow (<50%) and 2 or 3 cytopenias (absolute neutrophil count <1,500/mm(3), absolute reticulocyte count <40,000/mm(3), platelet count <100,000/mm(3)) lasting at least 6 weeks.
Results:
Twenty-four patients met the criteria for MAA. At a median follow-up of 66 months (range, 10-293), 16 patients (67%) progressed to SAA, 5 (21%) had persistent MAA, and 3 (12%) had complete resolution of MAA. No risk factors for progression could be identified.
Conclusions:
When childhood MAA is treated with supportive care alone, 2/3 of patients progress to SAA.
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