Unusual case report of acute evolution hairy cell leukemia in a young adult patient, Amazônia, Brazil

Hairy cell leukemia (HCL) is a rare disease of unknown origin and indolent course, which is detected in a complete blood count associated by pancytopenia and lymphocytes with cytoplasmic projections. This study presents a case report of a 31-year-old male patient, with pallor and no splenomegaly, who was admitted to the Municipal Hospital of Rondon do Pará, Amazônia, on December 31, 2018 to perform laboratory tests due to the worsening of his general condition. The complete blood count revealed: anemia (hemoglobin level of 7.5 g/dL and hematocrit level of 20%), thrombocytopenia (28,200/mm3) and hyperleukocytosis (179,000/mm3) while 88% of lymphocytes presented thin and elongated cytoplasmic projections suggestive of hairy cells. On January 7, 2019, the patient’s condition worsened, resulting in death before the diagnostic confirmation of the immunophenotyping test, which revealed a clonal population of 68.3% of hairy cells that expressed antigens CD19, CD20, CD79b, CD23, IgM, CD200, CD38, FMC-7, CD25 and CD103. It was not possible to determine which factors were decisive to this situation.A Leucemia de Células Pilosas (LCP) é uma doença rara, de origem desconhecida, de curso indolente, e que se apresenta no hemograma associada a pancitopenia e linfócitos com projeções citoplasmáticas. No presente estudo apresentamos o relato de caso de um paciente de 31 anos, masculino, hipocorado, sem esplenomegalia, admitido no Hospital Municipal de Rondon do Pará, Amazônia, no dia 31.12.2018 para a realização de exames laboratoriais em função de rebaixamento do estado geral. O hemograma revelou: anemia (7.5g/dL de hemoglobina e 20% de hematócrito), plaquetopenia (28.200/mm3) e hiperleucocitose (179.000/mm3) as custas de 88% de linfócitos com projeções citoplasmáticas finas e alongadas sugestivas de células pilosas. No dia 07.01.2019 houve piora do quadro do paciente com evolução a óbito antes mesmo da confirmação diagnóstica pelo exame de imunofenotipagem que revelou tratava-se de população clonal de 68,3% de células pilosas com expressão dos antígenos: CD19, CD20, CD79b, CD23, IgM, CD200, CD38, FMC-7, CD25 e CD103. Não tendo sido possível a determinação de quais fatores foram determinantes para esse quadro