A case of de novo B - cell prolymphocytic leukemia associated with false - positive direct antiglobulin test / 대한내과학회지

ABSTRACT

De novo B-cell prolymphocytic leukemia (B-PLL) is a distinct clinicopathologic entity that was first described in 1974 by Galton et al. B-PLL is characterized by marked lymphocytosis with predominance of prolymphocytes, often massive splenomegaly, minimal lymphadenopathy, often aggressive clinical course and frequently poor prognosis.We experienced a case of B-PLL associated with false-positive direct antiglobulin test. The patient was 52 year-old man who presented with marked leukocytosis (160.2x103/(mu)L) and 60% of characteristic prolymphocytes in the peripheral blood. The bone marrow aspirate showed dry tap and the PAS stain of peripheral blood smear showed positivity of prolymphocytes. The immunophenotyping of the leukemic prolymphocytes revealed the positivity of surface immunoglobulin (IgM, lambda type), HLA-DR, CD19 and CD5.