RESUMEN
Many blood group antigens, genetically controlled carbohydrate molecules, are found on the surface of uroepithelial cells and may affect bacterial adherence and increase the frequency of urinary tract infection (UTI) in adults. Sixty-two children aged 2 weeks to 17 years (mean, 2.3 years) who were hospitalized with fever in association with UTIs caused by Escherichia coli had complete (n = 50) or partial (n = 12) erythrocyte antigen typing to determine the role of erythrocyte antigens and phenotypes in UTI in children; 62 healthy children undergoing nonurologic elective surgery, matched 1 to 1 for age, sex, and race to the patient group, formed the control group. In univariate tests, patients and control subjects did not differ in ABO, Rh, P, Kell, Duffy, MNSs, and Kidd systems by the McNemar test of symmetry (p > 0.05). The frequency of the Lewis (Le) (a-b-) phenotype was higher (16/50 vs 5/50; p = 0.0076) and the frequency of the Le(a + b +) phenotype was lower (8/50 vs 16/50; p = 0.0455) in the patient population than in the control subjects. A stepwise logistic regression model to predict UTI with the explanatory variables A, B, O, M, N, S, s, Pl, Lea, and Leb showed that only the Lea and Leb antigens entered the model with p < 0.1. The Le(a-b-) phenotype was associated with UTI in this pediatric population. The relative risk of UTI in children with the Le(a-b-) phenotype was 3.2 (95% confidence interval, 1.3 to 7.9). Specific blood group phenotypes in pediatric populations may provide a means to identify children at risk of having UTI.
Asunto(s)
Bacteriuria/sangre , Infecciones por Escherichia coli/sangre , Antígenos del Grupo Sanguíneo de Lewis , Infecciones Urinarias/sangre , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Masculino , Fenotipo , Infecciones Urinarias/microbiologíaRESUMEN
A blinded, randomized, controlled study was designed to test whether multiple-dose surfactant therapy would improve pulmonary outcome in term infants with respiratory failure, resulting in a shortened period of extracorporeal membrane oxygenation (ECMO). Infants > or = 34 weeks of gestational age in severe respiratory failure and receiving ECMO were stratified by diagnosis and then randomly assigned to the treatment or the control group. Four doses of modified bovine lung surfactant extract (beractant) were administered to the surfactant group (n = 28), and an equal volume of air was administered to the control group (n = 28). Lung compliance was initially low in both groups; after treatment, values were higher with time in the surfactant group (F = 5.40, p = 0.026). The ECMO treatment period was significantly shorter in the surfactant group (mean +/- SD: 107 +/- 33 hours vs 139 +/- 54 hours for the control group; U = 232, p = 0.023). Tracheal aspirate concentrations of surfactant protein A were low in both groups, and then increased steadily to a higher level in the surfactant group (F = 2.58, p = 0.04). The overall incidence of complications after ECMO was decreased in the surfactant group (18% vs 46% for the control group; chi-square value = 5.004, p = 0.025). Radiographic scores, echocardiographic findings, incidence of intracranial or pulmonary hemorrhage and bronchopulmonary dysplasia, time to extubation, duration of oxygen therapy, and duration of hospitalization did not differ between the two groups. Beractant in this population improved pulmonary mechanics, increased surfactant protein A content in tracheal aspirate, decreased time on ECMO duration, and reduced disease complications.
Asunto(s)
Oxigenación por Membrana Extracorpórea , Pulmón/fisiología , Surfactantes Pulmonares/uso terapéutico , Insuficiencia Respiratoria/tratamiento farmacológico , Insuficiencia Respiratoria/terapia , Método Doble Ciego , Ecocardiografía , Oxigenación por Membrana Extracorpórea/efectos adversos , Oxigenación por Membrana Extracorpórea/métodos , Femenino , Glicoproteínas/análisis , Humanos , Recién Nacido , Intubación Intratraqueal , Pulmón/metabolismo , Rendimiento Pulmonar/fisiología , Masculino , Síndrome de Aspiración de Meconio/complicaciones , Síndrome de Circulación Fetal Persistente/complicaciones , Estudios Prospectivos , Proteolípidos/análisis , Proteínas Asociadas a Surfactante Pulmonar , Surfactantes Pulmonares/administración & dosificación , Surfactantes Pulmonares/análisis , Radiografía , Insuficiencia Respiratoria/diagnóstico por imagen , Factores de TiempoRESUMEN
To assess the effects of decreased erythrocyte production on the levels of serum erythropoietin in children, we measured simultaneous hemoglobin concentrations and erythropoietin in 18 children with iron deficiency anemia, 17 children with transient erythroblastopenia of childhood (TEC), and 7 children with aplastic anemia. In all but two patients (one with TEC; one with aplastic anemia), erythropoietin was measured at diagnosis, before institution of specific therapy for the anemia. There was a statistically significant inverse linear correlation between log10 erythropoietin and hemoglobin values for all patient groups (r = 0.904 to 0.912; p less than 0.005). A comparison of the slopes of the regressions for each patient group by analysis of covariance revealed a significantly steeper slope for the iron deficiency group (-0.553) versus the TEC (-0.287) and aplastic anemia (-0.256) groups (p = 0.0001). The difference in erythropoietin levels appeared greatest in patients whose presenting hemoglobin level was greater than 5 gm/dl. Decline in serum erythropoietin levels was more precipitous in the less severely anemic patients with iron deficiency anemia than in the patients with TEC or aplastic anemia. These data reveal quantitative and qualitative differences in the relationship between serum erythropoietin and hemoglobin levels when children with severe iron deficiency anemia versus those with TEC or aplastic anemia are considered, even though all three conditions are characterized by hypoproliferation of erythrocytes.