Pseudoreticulocytosis in a case of myelodysplastic syndrome.

A patient with normocytic anemia and marked and persistent reticulocytosis is presented. Causes responsible for blood loss and hemolytic diseases were excluded and, after bone marrow examination, myelodysplastic syndrome (refractory anemia) was diagnosed. In vitro reticulocyte survival studies suggested that reticulocytosis was a consequence of delayed maturation of the reticulocytes. Pseudoreticulocytosis may be an unusual presentation of myelodysplastic syndromes, because only 4 patients with such a finding have previously been reported.