Chronic pure thrombocytopenia in elderly patients. An aspect of the myelodysplastic syndrome.

Abstract

From a group of 276 elderly patients studied in the last 12 years in a department of nuclear medicine for investigating a chronic thrombocytopenia, 36 patients have an acquired disorder, with normal platelet life span, a normal megakaryocytic bone marrow count, and absence of any evident cause at the time of clinical evaluation. During the 2 to 10 subsequent years, 16 patients developed symptoms of the myelodysplastic syndrome, i.e., chronic aregenerative anemia, granulocytopenia, dysmyelopoiesis, and appearance of circulating blast cells; three of them died from acute myeloblastic leukemia. So a pure thrombocytopenia due to a platelet production defect, without any demonstrated functional platelet defect or morphologic dysmegakaryocytosis, may be a preleukemic syndrome. In the other 20 patients, with the same pure chronic thrombocytopenia, no malignant evolution has been seen with long follow-up delays, which is often also the case in pure refractory anemias. In the absence of objective criteria of a possible premalignant disorder, the classification of these cases is difficult, which it is also the case for the so-called refractory anemias. We suggest to individualize, in the classification of the myelodysplastic syndromes, a group of pure refractory thrombocytopenias. From a practical point of view such a diagnosis may be useful, at least to avoid inefficient and possibly harmful treatments.