Irradiation of blood components with ionizing radiation generated by a specific device is recommended to prevent transfusion-associated graft-versus-host disease. However, a linear accelerator can also be used in the absence of such a device, which is the case of the blood bank facility studied herein. In order to evaluate the quality of the irradiated packed red blood cells, this study aimed to determine whether the procedure currently employed in the facility is effective in inhibiting the proliferation of T lymphocytes without damaging blood components.The proliferation of T lymphocytes, plasma potassium levels, and the degree of hemolysis were evaluated and compared to blood bags that received no irradiation. Packed red blood cell bags were irradiated at a dose of 25 Gy in a linear accelerator. For this purpose, a container was designed to hold the bags and to ensure even distribution of irradiation as evaluated by computed tomography and dose-volume histogram.Irradiation was observed to inhibit the proliferation of lymphocytes. The percentage of hemolysis in irradiated bags was slightly higher than in non-irradiated bags (p-value >0.05), but it was always less than 0.4% of the red cell mass. Although potassium increased in both groups, it was more pronounced in irradiated red blood cells, especially after seven days of storage, with a linear increase over storage time.The findings showed that, at an appropriate dosage and under validated conditions, the irradiation of packed red blood cells in a linear accelerator is effective, inhibiting lymphocyte proliferation but without compromising the viability of the red cells.

Adult T-cell leukemia/lymphoma is a lymphoproliferative disorder of mature T lymphocytes associated with infection with human T-cell lymphotrophic virus type I (HTLV-I). Adult T-cell leukemia/lymphoma is characterized by clinical and laboratory polymorphism that allows it to be classified into four distinct subgroups: smoldering, chronic, acute and lymphomatous types. We present here two cases of adult T-cell leukemia/lymphoma, respectively in the acute and lymphomatous forms of the disease. Case 1 was a 35-year-old woman who presented abdominal distension accompanied by hepatosplenomegaly, adenomegaly, skin lesions, positivity for anti-HTLV-I antibodies and leukocytosis with the presence of flower cells. Case 2 was a 38-year-old man who was admitted with generalized lymphadenomegaly, positivity for anti-HTLV-I antibodies, hypercalcemia and osteolytic lesions. In this paper, we correlate the clinical-laboratory findings of these two cases with data in the literature. Key-words:Human T-cell lymphotrophic virus. Adult T-cell leukemia/lymphoma. Flower cell. RESUMO A leucemia/linfoma de células T do adulto é um distúrbio linfoproliferativo de linfócitos T maduros associado à infecção pelo vírus linfotrópico de células T humanas tipo I (HTLV-I).A leucemia/linfoma de células T do adulto tem polimorfismo clínico e laboratorial, que a classifica em quatro subgrupos distintos entre si: smoldering, crônica, aguda e linfomatosa. Apresentamos neste artigo, dois casos de leucemia/linfoma de células T do adulto, respectivamente, nas formas aguda e linfomatosa da doença. O caso 1: uma paciente de 35 anos apresentava distensão abdominal com hepatoesplenomegalia, adenomegalia, lesões cutâneas, anticorpos anti-HTLV-I positivo e leucocitose com presença de flower cell. O caso 2: homem de 38 anos, internado com linfadenomegalia generalizada, anticorpos anti-HTLV-I positivo, hipercalcemia e lesões osteolíticas. Neste artigo correlacionamos os achados clínicos e laboratoriais destes dois casos com dados da literatura. Palavras-chaves:Vírus linfotrópico de células T humanas. Leucemia/linfoma células T do Adulto. Flower cell.