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1.
Vox Sang ; 119(7): 712-719, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38597364

RESUMO

BACKGROUND AND OBJECTIVES: The isolation of neutrophils and subsequent detection of anti-human neutrophil antigens (HNA) antibodies are crucial in clinical medicine for the diagnosis of autoimmune neutropenia, neonatal alloimmune neutropenia (NAIN) and transfusion-related acute lung injury (TRALI). This study reports two cases of maternal anti-Fc-gamma-receptor-IIIb (FcγRIIIb) isoimmunization without NAIN symptoms and compares the efficiency of immunomagnetic negative selection (IMNS) with traditional dextran/Ficoll for neutrophil isolation in HNA serological assays. MATERIALS AND METHODS: Investigating two cases of maternal anti-FcγRIIIb isoimmunization, neutrophils from three donors were isolated from 8 mL of whole blood using IMNS and dextran/Ficoll. Serological assays included the granulocyte agglutination and immunofluorescence test, monoclonal antibody immobilization of granulocyte antigens and the LABScreen Multi (One Lambda). IMNS and dextran/Ficoll were compared in terms of cell yield, viability, time, cost and purity. RESULTS: Maternal anti-FcγRIIIb isoantibodies with FCGR3B gene deletion were detected in both cases. Newborns and fathers exhibited specific gene combinations: FCGR3B*02/FCGR3B*02 (Case 1) and FCGR3B*02/FCGR3B*03 (Case 2). IMNS outperformed dextran/Ficoll, yielding four times more neutrophils (average neutrophil counts: 18.5 × 103/µL vs. 4.5 × 103/µL), efficiently removing non-neutrophil cells and reducing processing time (30-40 min vs. 70-90 min), although it incurred a higher cost (2.7 times). CONCLUSION: Two cases of maternal anti-FcγRIIIb isoantibodies, unrelated to NAIN, were identified. Although neutropenia has not been described in these cases, we emphasize the importance of identifying asymptomatic cases with the potential for severe neutropenia. Additionally, IMNS is introduced as a rapid, high-yield, high-purity neutrophil isolation technique, beneficial for serological assays detecting anti-HNA antibodies.


Assuntos
Isoanticorpos , Neutrófilos , Receptores de IgG , Humanos , Neutrófilos/imunologia , Feminino , Receptores de IgG/imunologia , Isoanticorpos/imunologia , Isoanticorpos/sangue , Recém-Nascido , Proteínas Ligadas por GPI/imunologia , Masculino , Separação Imunomagnética/métodos , Adulto , Gravidez , Neutropenia/imunologia , Neutropenia/sangue
2.
Sci Rep ; 11(1): 20220, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642440

RESUMO

Neutrophils are essential to control several fungal infections. These cells are commonly known for their pro-inflammatory activities. However, some studies have demonstrated the anti-inflammatory properties of neutrophils during certain infectious diseases, culminating in the inhibition of T cell proliferation. Chromoblastomycosis (CBM) is a deep and progressive mycosis that affects thousands of people worldwide. Although neutrophil infiltrates are observed in the lesion histopathology, the fungus can overtake the immune system response and destroy the host-infected tissue. The present study demonstrated that neutropenic animals had an increase in the IL-6 production in the spleen and liver, followed by a lower fungal burden in these organs up to 14 days of infection. Neutropenic animals also showed a lower F. pedrosoi-specific antibody production 14-days post infection and higher T-cell proliferation in the in vitro experiments after stimulation with F. pedrosoi-purified proteins. Taken together, our results suggest that the presence of regulatory neutrophils in the mouse model of F. pedrosoi infection could act favoring the spread of the fungus and the chronicity of the infection. These findings shed light on the CBM treatment, which might target neutrophil polarization as a new therapy approach to treat CBM lesions.


Assuntos
Anticorpos/efeitos adversos , Antígenos Ly/imunologia , Cromoblastomicose/imunologia , Fonsecaea/patogenicidade , Neutropenia/imunologia , Neutrófilos/metabolismo , Linfócitos T/metabolismo , Animais , Polaridade Celular , Proliferação de Células , Cromoblastomicose/complicações , Modelos Animais de Doenças , Fonsecaea/imunologia , Humanos , Interleucina-6/metabolismo , Fígado/imunologia , Ativação Linfocitária , Camundongos , Neutropenia/induzido quimicamente , Baço/imunologia
3.
Transfusion ; 58(5): 1264-1270, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29451309

RESUMO

BACKGROUND: Neonatal alloimmune neutropenia results from maternal alloimmunization to human neutrophil antigens. The alloantibodies involved in neonatal alloimmune neutropenia are against human neutrophil antigens HNA-1a, HNA-1b, HNA-1c, HNA-1d, HNA-2, HNA-3a, HNA-4a, HNA-4b, and HNA-5a; however, to date, antibodies specific to HNA-3b have not been reported. STUDY DESIGN AND METHODS: Blood samples from 10,000 unselected neonates were analyzed, resulting in the selection of 88 neutropenic newborns (neutrophil count <1.5 × 109 /L) from 83 mothers (three pairs of twins and one triplet). HNA-3 genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism to identify the cases of maternal-fetal HNA-3 incompatibility. Serologic studies for detecting maternal HNA-3 alloantibodies were performed with the granulocyte agglutination test, the white blood cell immunofluorescence test, and a LABScreen Multi-HNA Kit. RESULTS: Genotyping studies identified 13 of 88 (14.8%) instances of maternal-fetal HNA-3 incompatibility, with all mothers typed as HNA-3a/a and neonates typed as HNA-3a/b. Serologic studies revealed that five of 13 (38.5%) mothers carried anti-HNA-3b plus human leukocyte antigen antibodies and that three of 13 (23.1%) mothers had anti-HNA-3b without human leukocyte antigen antibodies. CONCLUSION: Here, we report the first three cases of neonatal alloimmune neutropenia associated with HNA-3b antibodies resulting in a neonatal alloimmune neutropenia incidence of one in 3333 live births.


Assuntos
Doenças do Recém-Nascido/imunologia , Isoanticorpos/imunologia , Isoantígenos/imunologia , Neutropenia/imunologia , Incompatibilidade de Grupos Sanguíneos/etiologia , Genótipo , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/etiologia , Isoanticorpos/efeitos adversos , Neutropenia/etiologia
4.
Braz. j. infect. dis ; 20(4): 354-359, July-Aug. 2016. tab
Artigo em Inglês | LILACS | ID: biblio-828120

RESUMO

Abstract Introduction Invasive mold disease is an important complication of patients with hematologic malignancies, and is associated with high mortality. A diagnostic-driven approach has been an alternative to the classical empiric antifungal therapy. In the present study we tested an algorithm that incorporated risk stratification using the D-index, serial serum galactomannan and computed tomographic-scan to guide the decision to start antifungal therapy in neutropenic patients. Patients and methods Between May 2010 and August 2012, patients with acute leukemia in induction remission were prospectively monitored from day 1 of chemotherapy until discharge or death with the D-index and galactomannan. Patients were stratified in low, intermediate and high risk according to the D-index and an extensive workup for invasive mold disease was performed in case of positive galactomannan (≥0.5), persistent fever, or the appearance of clinical manifestations suggestive of invasive mold disease. Results Among 29 patients, 6 (21%), 11 (38%), and 12 (41%) were classified as high, intermediate, and low risk, respectively. Workup for invasive mold disease was undertaken in 67%, 73% and 58% (p = 0.77) of patients in each risk category, respectively, and antifungal therapy was given to 67%, 54.5%, and 17% (p = 0.07). Proven or probable invasive mold disease was diagnosed in 67%, 45.5%, and in none (p = 0.007) of high, intermediate, and low risk patients, respectively. All patients survived. Conclusion A risk stratification using D-index was a useful instrument to be incorporated in invasive mold disease diagnostic approach, resulting in a more comprehensive antifungal treatment strategy, and to guide an earlier start of treatment in afebrile patients under very high risk.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Aspergilose/tratamento farmacológico , Algoritmos , Fusariose/tratamento farmacológico , Mananas/sangue , Antifúngicos/uso terapêutico , Neutropenia/imunologia , Aspergilose/diagnóstico , Aspergilose/imunologia , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/microbiologia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/microbiologia , Tomografia Computadorizada por Raios X , Estudos Prospectivos , Sensibilidade e Especificidade , Medição de Risco , Fusariose/diagnóstico , Fusariose/imunologia , Mananas/imunologia , Neutropenia/microbiologia
5.
Braz J Infect Dis ; 20(4): 354-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27280789

RESUMO

INTRODUCTION: Invasive mold disease is an important complication of patients with hematologic malignancies, and is associated with high mortality. A diagnostic-driven approach has been an alternative to the classical empiric antifungal therapy. In the present study we tested an algorithm that incorporated risk stratification using the D-index, serial serum galactomannan and computed tomographic-scan to guide the decision to start antifungal therapy in neutropenic patients. PATIENTS AND METHODS: Between May 2010 and August 2012, patients with acute leukemia in induction remission were prospectively monitored from day 1 of chemotherapy until discharge or death with the D-index and galactomannan. Patients were stratified in low, intermediate and high risk according to the D-index and an extensive workup for invasive mold disease was performed in case of positive galactomannan (≥0.5), persistent fever, or the appearance of clinical manifestations suggestive of invasive mold disease. RESULTS: Among 29 patients, 6 (21%), 11 (38%), and 12 (41%) were classified as high, intermediate, and low risk, respectively. Workup for invasive mold disease was undertaken in 67%, 73% and 58% (p=0.77) of patients in each risk category, respectively, and antifungal therapy was given to 67%, 54.5%, and 17% (p=0.07). Proven or probable invasive mold disease was diagnosed in 67%, 45.5%, and in none (p=0.007) of high, intermediate, and low risk patients, respectively. All patients survived. CONCLUSION: A risk stratification using D-index was a useful instrument to be incorporated in invasive mold disease diagnostic approach, resulting in a more comprehensive antifungal treatment strategy, and to guide an earlier start of treatment in afebrile patients under very high risk.


Assuntos
Algoritmos , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Fusariose/tratamento farmacológico , Mananas/sangue , Neutropenia/imunologia , Adulto , Idoso , Aspergilose/diagnóstico , Aspergilose/imunologia , Feminino , Fusariose/diagnóstico , Fusariose/imunologia , Galactose/análogos & derivados , Humanos , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/microbiologia , Masculino , Mananas/imunologia , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/microbiologia , Neutropenia/microbiologia , Estudos Prospectivos , Medição de Risco , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Adulto Jovem
6.
Antimicrob Agents Chemother ; 59(1): 53-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25313208

RESUMO

Therapeutic nonequivalence of generic antibiotics may lead to treatment failure and enrichment of resistance. However, there has been no demonstration that an equivalent generic displays the same resistance selection profile as the innovator drug. We aimed to test this hypothesis with five generic versions of ciprofloxacin by assessing their pharmaceutical equivalence with microbiological assays and their efficacy against Pseudomonas aeruginosa PAO1 in the neutropenic murine thigh infection model. One equivalent generic was selected for analysis by high-pressure liquid chromatography-tandem mass spectrometry (LC-MS/MS), to confirm chemical identity, and resistance selection experiments in a hollow-fiber (HF) system simulating two clinical dosing regimens. Total and resistant populations were measured, and the MICs of the resistant cells with and without an efflux pump inhibitor were determined. LC-MS/MS found no differences between products, and the innovator and the generic selected resistance with the same magnitude and mechanism after 7 days of treatment in the HF system, supporting the fact that a generic with demonstrated equivalence in vivo is also equivalent regarding resistance selection.


Assuntos
Antibacterianos/farmacocinética , Ciprofloxacina/farmacocinética , Medicamentos Genéricos/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Animais , Antibacterianos/uso terapêutico , Ciprofloxacina/uso terapêutico , Camundongos , Testes de Sensibilidade Microbiana , Neutropenia/imunologia , Equivalência Terapêutica
8.
Pediatr Infect Dis J ; 32(2): 136-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23014359

RESUMO

BACKGROUND: Interleukin-1 receptor antagonist polymorphism (ILRN) 2 (ILRN*2) has been associated with a poor outcome in septic patients because of an elevated production of anti-inflammatory cytokines. In >70% of patients, morbidity and mortality in childhood acute lymphoblastic leukemia is caused by infections. The aim of this study was to determine the association between this polymorphism and the frequency of septic shock from the time of diagnosis until completion of treatment. METHODS: This cohort study was conducted in 57 consecutive children with acute lymphoblastic leukemia. At the end of follow-up, children were stratified according to their IL1RN polymorphism (ILRN*1/ILRN*2), evaluating the impact of genotype on the severity of febrile neutropenic events during their treatment. RESULTS: Overall survival was 80% at 55 months after treatment. The average number of febrile neutropenic events in this cohort was 2.82 per patient. Genotype distribution was 50.9% for homozygote IL-1RN*1, 38.6% for heterozygote ILRN*1/ILRN*2 and 10.5% for homozygote IL-1RN*2. The risk of presenting septic shock for homozygote IL1RN*2/IL1RN*2 and heterozygote ILRN*1/ILRN*2 patients was significantly greater (odds ratio, 45; P = 0.001) adjusted for age, gender, risk of leukemia and presence of pathogenic bacteria. Genotype IL-1RN*2 is associated with the risk of development of septic shock in children with acute lymphoblastic leukemia. Further research in larger population-based studies is needed to replicate these findings. CONCLUSIONS: This information would allow us to identify more predictive factors in this group of acute lymphoblastic leukemia patients in whom this information is lacking to establish an earlier and more aggressive approach.


Assuntos
Proteína Antagonista do Receptor de Interleucina 1/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Choque Séptico/genética , Adolescente , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Feminino , Febre/genética , Febre/imunologia , Seguimentos , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Proteína Antagonista do Receptor de Interleucina 1/imunologia , Modelos Logísticos , Masculino , Neutropenia/genética , Neutropenia/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Choque Séptico/imunologia , Estatísticas não Paramétricas
9.
J Pediatr Hematol Oncol ; 33(4): 276-80, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21516023

RESUMO

BACKGROUND: Febrile neutropenia (FN) and infection-related mortality are major problems for children with cancer in low-income countries. Identifying predictors for adverse outcome of FN in low-income countries permits targeted interventions. We describe the nature and predictors of microbiologically documented infection (MDI) and mortality of FN in children with cancer in El Salvador. METHODS: We examined Salvadoran pediatric oncology patients admitted with FN over a 1-year period. Data were collected prospectively. Demographic, treatment, and admission-related variables were examined as predictors of outcomes. RESULTS: Hundred six FN episodes among 85 patients were included. Twenty-three of 106 episodes (22%) were microbiologically documented; 13 of 106 episodes (12%) resulted in death. Gram-positive and gram-negative organisms were isolated in 14 of 23 and 11 of 23 specimens; polymicrobial infections were common (11 of 23 episodes of MDI). Older age decreased the MDI risk [odds ratio (OR) per year=0.87, 95% confidence interval (CI), 0.75-0.99; P=0.04] while increasing number of days since the last chemotherapy increased the risk (OR=1.03 per day, 95% CI, 1.01-1.04; P=0.002). Pneumonia diagnosed either clinically (OR=6.6, 95% CI, 1.8-30.0; P=0.005) or radiographically (OR=5.5, 95% CI, 1.7-18.1; P=0.005) was the only predictor of mortality. CONCLUSIONS: In El Salvador, polymicrobial infections were common. Pneumonia at admission identified children with FN at high risk of death; these children may benefit from targeted interventions.


Assuntos
Febre/mortalidade , Infecções por Bactérias Gram-Negativas/mortalidade , Infecções por Bactérias Gram-Positivas/mortalidade , Neoplasias/mortalidade , Neutropenia/mortalidade , Adolescente , Criança , Pré-Escolar , El Salvador/epidemiologia , Feminino , Febre/imunologia , Febre/microbiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Humanos , Lactente , Masculino , Neoplasias/imunologia , Neutropenia/imunologia , Pneumonia Bacteriana/imunologia , Pneumonia Bacteriana/mortalidade , Valor Preditivo dos Testes , Prevalência , Fatores de Risco
10.
Rev. chil. reumatol ; 25(1): 26-36, 2009.
Artigo em Espanhol | LILACS | ID: lil-526893

RESUMO

Las enfermedades autoinmunes son trastornos secundarios a una des regulación del sistema inmune; éste pierde la capacidad de autotolerancia, y produce un daño crónico, continuo y progresivo. Son patologías muy diversas y pueden llegar a afectar hasta el 5 por ciento de la población. Pueden ser clasificadas en sistémicas u órgano-especificas, dependiendo si el antígeno reconocido es exclusivo del tejido target. A este grupo de enfermedades corresponden las citopenias autoinmunes, condiciones que se caracterizan por disminución del recuento de glóbulos rojos, plaquetas, leucocitos o la mezcla de ellos. Si bien los mecanismos patogénicos que participan en producción de cada una de ellas son similares, cada la tiene características que la hacen particularmente interesante. De esta manera tenemos que la anemia hemolítica autoinmune (AHAI) en un síndrome clínico que se produce debido a la disminución de glóbulos rojos secundaria a una destrucción exagerada de ellos, mediada por la alteración de la respuesta inmune, en la que los antígenos de la membrana de estas células son reconocidos como extraños por nuestro sistema inmune. La clasificación de la AHA/ está dada por la temperatura óptima de unión entre el anticuerpo y la membrana del glóbulo rojo; de esta forma, tenemos tres grandes grupos: por Anticuerpos calientes (WAHA), por Anticuerpos fríos (CAHA) y Mixtas (mediadas por anticuerpos calientes y frios). El diagnóstico de AHAl se confirma con la demostración de anticuerpos y/o proteínas del complemento en la superficie de los eritrocitos; entre ellos encontramos: Coombs directo y Coombs indirecto, test de Coombs recto anti-lgM , búsqueda de C3b en la membrana del glóbulo rojo y finalmente la prueba cualitativa de Donath-Landsteine Las trombopenias autoinmunes corresponden a un grupo de desórdenes que se caracterizan por tener un recuento plaquetario bajo 150.000, mediado por una alteración del sistema inmune. (3.14) La trombocitopenia autoinmune puede ser...


Autoimmune diseases are disorders secondary to a deregulation of the immune system, which loses the capacity for self-tolerance, resulting in chronic, continuous and progressive damage. These pathologies are very diverse and affect up to 5 percent of the population. They can be classified into systemic or organ-specific, depending on whether the recognized antigen is unique to the target tissue. Autoimmune cytopenias belong to this group of diseases and are characterized by a decreased count of red blood cells, platelets, leukocytes, or a mix of these. While the pathogenic mechanisms involved in the production of each are similar, each has features that make it particularly interesting. We have autoimmune hemolytic anemia (AlHA), which is a clinical syndrome that occurs due to a decreased number of red blood cells secondary to an exaggerated destruction of the same, mediated by an alteration of the immune response, in which the membrane antigens of these cells are recognized as foreign by our immune system. The classification of AIHA is given by the optimum bond temperature between the antibody and red blood cell membrane. There are 3 main groups: warm antibodies(WAHA), Cold antibodies (CAHA) and mixed (mediated by hot and cold antibodies). AIHA diagnosis is confirmed with the demonstration of antibodies and/or complement proteins on the surface of red blood cells, among these are the direct and indirect Coombs test, direct anti-IgM Coombs test, the search for C3b in the membrane of the red cell and, finally, the qualitative Donath-Landsteiner test. Autoimmune thrombocytopenia isassociated with a group of disorders characterized by a platelet count under 150,000, mediated by an alteration of the immune system.(3-14) Autoimmune thrombocytopenia can be classified as primary or secondary, and these, in turn, into acute and chronic, depending on whether they last 6 months or more, respectively. Antibodies that react against the glycoproteins of the plate...


Assuntos
Humanos , Anemia Hemolítica Autoimune/imunologia , Neutropenia/imunologia , Púrpura Trombocitopênica Idiopática/imunologia , Anticorpos , Autoimunidade , Doenças Autoimunes/imunologia , Granulócitos , Hemoglobinúria Paroxística/imunologia , Sistema Imunitário , Receptores Fc , Linfócitos T
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