Microsoft Word - AHA228BF

Valder R. Arruda, MD, Hematology-Hemotherapy Center, State University of Campinas, CP 6198, BR-13081-970 Campinas, SP (Brazil), Fax+55 19 239 31 81/239 31 14 Autoimmune thrombocytopenic purpura (AITP) is characterized by the development of antibodies against platelet membrane proteins which results in their phagocytosis and destruction by the monocyte-macrophage system [1]. The production of platelet autoantibodies may occur as an idiopathic pathogenesis or in conjunction with other autoimmune diseases, cancer, drugs or various infections and may result in secondary autoimmune thrombocytopenia [2, 3]. Viral infections affecting mega-karyocytes or platelets which result in a clinical picture of AITP are commonly associated with a self-limited course although a chronic evolution is now recognized in HIV infection [2-5]. Thrombocytopenia has been described in acquired and congenital infections by cytomegalovirus (CMV) but the mechanism of the decrease in the platelet number could be similar to that of AITP or that of myelo-suppression of hematopoietic progenitor cells [3]. Healthy adults rarely manifest clinical infections by CMV although there are a few cases of association between CMV infection and secondary AITP [6-10]. Here we describe the case of a nonimmunosuppressed adult with severe thrombocytopenia related to a subclinical CMV infection in which total resolution of the condition was achieved only after specific antiviral therapy. A 34-year-old man was admitted to the outpatient clinic with a 7-day history of an abrupt onset of petechiae in the lower extremities. On admission, he was in a healthy condition without fever, and had no lymphadenopathy or hepatosplenomegaly. He reported that he had suffered from transitory fever and generalized fatigue 3 weeks previously. No medication was used at the time and the resolution was spontaneous. The laboratory findings included a platelet count of 12 × 10/1, hemoglobin of 13.8 g/dl, hematocrit of 46.2%, red blood cell counts of 5.63 × 10/1, and a reticulocyte count of 2.4%. The white blood cell count was 11.5 × 10/1 and inspection of the blood smear revealed 24% polymorphonuclear leukocytes, 4% eosin-ophils, 4% monocytes, and 68% lymphocytes, most of them with atypical