title: Disturbances of T lymphocyte subsets preceding refractory anemia with excess blasts in transformation in a child.
abstract: A 5-year-old girl with refractory anaemia with excess of blasts in transformation (RAEBT) terminating in acute nonlymphocytic leukemia is reported. The patient's serum had an inhibitory effect on normal hemopoiesis. T cell subsets defined by monoclonal antibodies revealed a decrease in helper/inducer T cell population (OKT4-positive cells) and inversion of the T4/T8 ratio. It is suggested that imbalance in immunoregulatory T cells, which has a crucial role in the control of hemopoiesis, may be a primary event in the pathogenesis of myelodysplastic syndrome which eventually develops into an overt leukemia.
mesh_terms: D000208:Acute Disease; D000754:Anemia, Refractory, with Excess of Blasts / Q000150:complications*; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007938:Leukemia / Q000209:etiology*; D008213:Lymphocyte Activation; D009190:Myelodysplastic Syndromes / Q000209:etiology / Q000276:immunology; D013601:T-Lymphocytes / Q000145:classification*