[Hematological evaluation of megakaryocytic vacuolar degeneration in patients with idiopathic thrombocytopenic purpura].

ABSTRACT

Variable degrees of vacuolar degeneration of the cytoplasm of megakaryocytes(MEG) have been recognized in patients with idiopathic thrombocytopenic purpura(ITP). It has been questioned whether this degeneration is specific to the disease, as it is not seen in all patients, and few reports have examined its physiological relationship to the disease process. This study examined the vacuolation and its relationship to platelet count(PLTc) by image analysis, measuring the vacuolar area and the MEG area. However, it was inappropriate to evaluate the vacuolar area alone, since variations in the MEG area among patients influenced the vacuolar area. When the proportion of the vacuolar area relative to total MEG was defined as %VAC, the value for ITP patients was higher than in control cases (p < 0.05). However, there was no correlation between %VAC and PLTc. It was thought that this reflected the previous reports doubting the disease specificity of this feature. When all the ITP patients were generalized, the age at onset was wide, and both chronic type and repetitive type cases were included. However, in 4 ITP cases in which it was possible to follow the treatment progress, the %VAC was well correlated with the change in PLTc. It was concluded that MEG cytoplasmic vacuolation in ITP is morphologically meaningful if it can be followed over the course of treatment.