Resumo
JUSTIFICATIVA E OBJETIVOS: Os testes de coagulação (hemograma e tempo de protrombina) foram inicialmente concebidos como uma forma de rastrear e acompanhar coagulopatias congênitas raras e o hemograma é o que fornece o número de plaquetas por milímetro cúbico. O objetivo deste relato foi apresentar o caso de uma paciente que apresentava um número de plaquetas extremamente baixo quando sua amostra de sangue era analisada em tubo com EDTA e um número normal quando analisada com citrato, alertando para o risco de administração errônea de hemoderivados. RELATO DO CASO: Paciente do sexo feminino, 40 anos, ASA II. Em 2001, apresentou plaquetopenia no hemograma e foi encaminhada para o hematologista em Manaus, AM, sendo realizada esplenectomia nesse mesmo ano, com diagnóstico de púrpura trombocitopênica idiopática. Com a persistência da plaquetopenia nos hemogramas foi verificado na ecografia de abdômen: imagem hipoecóica de ecotextura semelhante à esplênica, medindo 2,0 × 1,7 cm, forma esférica, conteúdo bem definido (baço acessório) e indicada esplenectomia de baço acessório. Após uma hora de operação, foram colhidas amostras para hemograma e bioquímica: Hb = 11,3 g.dL-1; Ht = 33,4%; Plaquetas = 35.000.µL-1; TAP = 15,2 (86,0% Atividade) (RNI = 1,09). Em virtude do sangramento mínimo no campo cirúrgico, foi solicitado novo exame com citrato para dosagem de plaquetas (resultado: 138.000 plaquetas). CONCLUSÕES: O resultado anômalo em um exame isolado sem correspondência com a clínica do paciente não deve guiar a terapêutica. Todos os exames têm uma porcentagem definida de erros, e a busca desses erros técnicos impede que uma terapêutica errônea seja usada.
Palavras-chave
EXAMES COMPLEMENTARES, EXAMES COMPLEMENTARES, SANGUE
Abstract
BACKGROUND AND OBJECTIVES: Coagulation tests (CBC and prothrombin time) were initially conceived as a mean of screening and following rare congenital coagulopathies; the CBC provides the number of platelets per cubic milliliter. The objective of this report was to present the case of a patient who presented with an extremely low number of platelets when her blood was analyzed in an EDTA-containing tube and its numbers were normal when the blood was analyzed with citrate, alerting for the risk of erroneously administering blood products. CASE REPORT: This is the case of a 40-year old female patient, ASA II. In 2001 she presented with thrombocytopenia and was referred to a hematologist in Manaus, in the state of Amazonas, Brazil and underwent splenectomy that same year with a diagnosis of idiopathic thrombocytopenic purpura. Since her CBCs continued to show thrombocytopenia, an abdominal ultrasound was done and showed a spherical hypoechoic image, with an echotexture similar to the spleen, measuring 2.0 × 1.7 cm, with well-defined contents (accessory spleen), and a splenectomy was indicated. One hour into the surgery, blood samples were drawn for CBC and chemistry: Hb = 11.3 g.dL-1; Ht = 33.4%; Platelets = 35,000.µL-1; PT = 15.2 (86.0% Activity) (INR = 1.09). Due to the minimal blood loss in the surgical field, a new test with citrate was requested to determine the platelet count (results: 138,000 platelets). CONCLUSIONS: The anomalous result of an isolated exam without corresponding clinical signs should not guide the treatment. All exams have a defined percentage of errors and the search for those technical errors can avoid the use of the wrong treatment.
Keywords
BLOOD, COMPLEMENTARY EXAMS, COMPLEMENTARY EXAMS
Referencias
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