Avaliação da fração e da contagem absoluta de plaquetas imaturas no diagnóstico da trombocitopenia imune em pacientes pediátricos

• Ano de defesa: 2026
• Autor(a) principal: Nascimento, Fernanda Gomes
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; Brasil; UFSM; Programa de Pós-Graduação em Ciências Farmacêuticas; Centro de Ciências da Saúde
• Palavras-chave em Português: Trombocitopenia imune; Fração de plaquetas imaturas; Contagem absoluta de plaquetas imaturas; Diagnóstico; Pediatria; Immune thrombocytopenia; Immature platelet fraction; Absolute immature platelet count; Diagnosis; Pediatrics; CNPQ::CIENCIAS DA SAUDE::FARMACIA
• Link de acesso: http://repositorio.ufsm.br/handle/1/39064

Primary immune thrombocytopenia (ITP) is characterized by a reduction in platelet count to values below 100 × 10³/mm³, after exclusion of other causes, presenting wide clinical variability in the pediatric population. Its pathophysiology involves peripheral destruction mediated by autoantibodies and reduced platelet production. Given the need for auxiliary diagnostic tools, this study aimed to evaluate the usefulness of the immature platelet fraction (IPF) and the absolute immature platelet count (AIPC) in the diagnosis of ITP in pediatric patients. This is a cross-sectional study, including patients aged 0 to 18 years with a recent diagnosis of ITP and a control group composed of individuals without hematological alterations. It was observed that the IPF was approximately ten times higher in the ITP group compared to the control group, while the AIPC showed a significant reduction, reflecting increased bone marrow production associated with limitation of the total platelet count. Both parameters demonstrated high diagnostic accuracy, with area under the curve values greater than 0.95. The IPF cutoff point was 6.25%, with a sensitivity of 93.1% and a specificity of 95.07%, while the AIPC presented a cutoff point of 2.82, with a sensitivity of 89.66% and a specificity of 92.25%. There was no statistically significant difference between the parameters, demonstrating equivalent diagnostic performance. Thus, IPF and AIPC demonstrate high potential as laboratory markers in ITP, consistently reflecting its pathophysiology and contributing to a more precise diagnostic evaluation, especially in the pediatric context, where the etiological differentiation of thrombocytopenia remains challenging.