Hemophagocytic lymphohistiocytosis: a case series analysis in a pediatric hospital

Abstract Introduction Hemophagocytic lymphohistiocytosis (HLH) is a rare clinical laboratory condition with high mortality rates, resulting from ineffective overactivation of the immune system. Data in the Brazilian literature is scarce, contributing to the challenge in standardizing conducts and performing an early diagnosis of HLH. Objective To describe the clinical, laboratory, and evolutionary findings on HLH patients treated at a pediatric hospital. Methods This is an observational, cross-sectional and retrospective study on children diagnosed with HLH, hospitalized between 2009 and 2019. The diagnostic criteria were those described in the Histiocyte Society protocol. The authors evaluated HLH patient laboratory tests, myelograms and bone marrow biopsies, clinical characteristics and therapy. Results Twenty-three patients were included, 52.2% of whom were males. The age at diagnosis ranged from one to one hundred and eighty months. Four cases were classified as Primary HLH and nineteen, as Secondary HLH. The main triggers were infections and rheumatological diseases. All children had bicytopenia, and 95.4% had hyperferritinemia. Nineteen patients had liver dysfunction, sixteen had neurological disorders and fourteen had kidney injury. Pulmonary involvement was seen in 61.9%, acting as a worse prognosis for death (p= 0.01). Nine patients underwent the immuno-chemotherapy protocol proposed in the HLH 2004. The time to confirm the diagnosis varied from five to eighty days. The lethality found was 56.3%. Conclusions The present study is the most extensive retrospective exclusively pediatric study published in Brazil to date. Despite the limitations, it was possible to demonstrate the importance of discussing HLH as a pediatric emergency.

Hemophagocytic lymphohistiocytosis: a case series analysis in a pediatric hospital.

INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is a rare clinical laboratory condition with high mortality rates, resulting from ineffective overactivation of the immune system. Data in the Brazilian literature is scarce, contributing to the challenge in standardizing conducts and performing an early diagnosis of HLH. OBJECTIVE: To describe the clinical, laboratory, and evolutionary findings on HLH patients treated at a pediatric hospital. METHODS: This is an observational, cross-sectional and retrospective study on children diagnosed with HLH, hospitalized between 2009 and 2019. The diagnostic criteria were those described in the Histiocyte Society protocol. The authors evaluated HLH patient laboratory tests, myelograms and bone marrow biopsies, clinical characteristics and therapy. RESULTS: Twenty-three patients were included, 52.2% of whom were males. The age at diagnosis ranged from one to one hundred and eighty months. Four cases were classified as Primary HLH and nineteen, as Secondary HLH. The main triggers were infections and rheumatological diseases. All children had bicytopenia, and 95.4% had hyperferritinemia. Nineteen patients had liver dysfunction, sixteen had neurological disorders and fourteen had kidney injury. Pulmonary involvement was seen in 61.9%, acting as a worse prognosis for death (p = 0.01). Nine patients underwent the immuno-chemotherapy protocol proposed in the HLH 2004. The time to confirm the diagnosis varied from five to eighty days. The lethality found was 56.3%. CONCLUSIONS: The present study is the most extensive retrospective exclusively pediatric study published in Brazil to date. Despite the limitations, it was possible to demonstrate the importance of discussing HLH as a pediatric emergency.

Estudo da proliferação celular e da expressão da proteína bcl-2 em crianças com histiocitoses das células de Langerhans / The study of the cellular proliferation and the bcl-2 protein expression in children with Langerhans cell histiocytosis

Foram realizados estudos imunohistoquímicos em 36 materiais de biópsias de crianças com histiocitoses das células de Langerhans. O anticorpo monoclonal MIB-1 foi utilizado para determinação dos índices proliferativos das lesões e o anticorpo monoclonal bcl-2 para detecção da proteína bcl-2, inibidora da apoptose. Os pacientes foram divididos em dois grupos de doenças: localizada e disseminada. Em cinco casos das formas localizadas e em um caso das formas localizadas houve positividade para o anticorpo bcl-2, não sendo observado correlação com as evoluções clínicas dos pacientes. Embora os índices percentuais de células proliferativas determinadas pelo MIB-1 tenham sido maiores nas formas disseminadas, não houve diferença estatisticamente significante entre os dois grupos de doenças. Também não foi observado correlação entre altos índices proliferativos e más evoluções clínicas / Immunohistochemical studies were performed in 36 biopsies materials of children with Langerhans cell histiocytosis. The MIB-1 monoclonal antibody was used to determine the lesions proliferative index and the bcl-2 monoclonal antibody, to detect the bcl-2 protein, inhibitive of apoptosis. The patients were divided in two groups of diseases: restrictive and extensive. In five cases of restricted disease and in one case of extensive disease, there was positiveness for the bcl-2 antibody, but correlation to clinical evolution of the patients was not observed. Although the proliferative cell percentage index determined by MIB-1 antibody was higher in the extensive disease group, there was not a statistically significant difference between the two diseases groups. It was also not observed correlation between high proliferative index and bad...

Expressão dos marcadores mielóides e prognóstico das leucemias / myeloid markers expression and prognosis of acute lymphoid leukemia

Objetivos: avaliar os marcadores mielóides positivos como fator de risco para a sobrevida livre de doença e mortalidade em crianças com leucemia linfóide aguda. Casuística e métodos: d=foram revisados 84 prontuários de crianças com leucemia linfóide aguda do Hospital Pequeno Princípe de Curitiva, PR ...