RESUMEN
El sindrome Urémico Hemolítico D+ (SUH) es la segunda causa de insuficiencia renal crónica terminal (IRCT) en edad pediátrica. La proteinuria es el principal modulador de la evolución a la cronicidad. En un grupo de pacientes tratados con dieta controlada en proteínas e inhibidores de la enzima de conversión de la Angiotensina II se demostró un enlentecimiento significativo en la progresión de la nefropatía a la IRCT. El objetivo de este trabajo fue evaluar, en una primera etapa, el impacto de la dieta normoproteica y normosódica sobre la proteinuria en pacientes con nefropatía secuelar por SUH y función renal normal (CI Cr >80ml/min/1.73m2). Métodos: como parte de un estudio de fase III longitudinal, multicéntrico, aleatorizado, doble ciego, de grupos paralelos (placebo y activo controlado con enalpril y losartan), se evaluó la diferencia entre la proteinuria antes y después de una dieta normósódica y mormoprotica, indicada según RDA. La ingesta proteica fue estimada mediante recordtorio de 72 horas y el cálculo de excreción de urea en orina de 24 horas. La proteinuria se dosó en orina de 24 hs. al comienzo del estudio, a los 30 y 60 días. Resultados: se incluyeron 102 pacientes cuyo rango de proteinuria fue entre 5.3 y 40.0 mg/kg/día de los cuales negativizaron 65 (63.7 por ciento) y no respondieron 37 (36,3 por ciento ). La mediana de edad del comienzo de la enfermedad fue de 16,5 meses (rango: 7.0-85.0 meses). El tiempo de evolución post SUG fue de 4.0 a 155.0 meses (mediana 48.0 meses) El valor de la proteinuria inicial en los 65 niños que respondieron fue de x 9.83 mg/kg/día (ES 0 o,34) y post dieta de de x =2,44 (ES 0 0,12) P < 0.0001. La media de las diferencias entre la natriuresis pre y post dieta no fue estadísticamente diferente de 0; t = 0,97 (x /ES). Conclusión: la dieta normoproteica es capaz de normalizar la proteinuria en el 63.7 por ciento de los pacientes con proteinuria significativa secundaria a SUH y función renal normal.
Asunto(s)
Lactante , Preescolar , Niño , Adolescente , Enalapril/uso terapéutico , Losartán/uso terapéutico , Proteinuria/dietoterapia , Síndrome Hemolítico-Urémico , Estudios Longitudinales , Estudios Multicéntricos como Asunto , Método Doble CiegoRESUMEN
Serum erythropoietin (EPO) levels were measured in ten previously non-transfused children with hemolytic uremic syndrome (HUS). Complete blood cell count, serum EPO, and renal function tests were carried out upon admission and weekly thereafter. Blood samples were obtained: (1) prior to the first transfusion; (2) after the first transfusion but before recovery from renal failure; (3) during the recovery stage. All patients required transfusions (mean 1.8+/-0.8 per child). Absolute values of EPO correlated positively with the hematocrit during the three stages (r = 0.53, 0.36, and 0.12, respectively) which is opposite to expected results. The observed EPO logarithm/predicted EPO logarithm upon admission was low (0.70+/-0.08), falling further during stage 2 (0.57+/-0.03), but increasing thereafter (0.78+/-0.07) without reaching normal values. The reticulocyte production rate followed a parallel course (0.74+/-0.14, 0.54+/-0.11, and 0.60+/-0.10, respectively). On comparing the observed serum EPO levels with those expected, 9 of 11 pre-transfusion samples showed low values; in stage 2, all samples were below normal; in the recovery phase most (77.8%) were still low. Our results show an inadequate EPO synthesis in children with HUS, which could play an important pathogenic role, since it aggravates the severity of the existing hemolytic anemia; the secondary inhibitory effect of repeated transfusions exacerbates this inadequate synthesis.
Asunto(s)
Eritropoyetina/sangre , Síndrome Hemolítico-Urémico/sangre , Transfusión Sanguínea , Preescolar , Humanos , LactanteRESUMEN
Since resistance to several oral antimicrobials useful for the treatment of pediatric urinary tract infections (UTI) is overwhelming in Argentina, an in vitro investigation was performed testing 400 isolates obtained from urines of children suffering UTI's, 200 collected in 1990 and 200 in 1991. Their susceptibility against oral antimicrobials marketed in Argentina and appropriate for the treatment of UTI was determined by the agar dilution methods. An increase of the resistance to aminopenicillin combined with beta-lactamase inhibitors and to fluoroquinolones was observed comparing the two periods. Cefpodoxime (CPD), cefixime and fluoroquinolones except norfloxacin were the sole oral antimicrobials showing in vitro activity at the 90 per cent level. Unfortunately fluoroquinolones are not yet approved for pediatric use. Consequently we realized an in vitro and in vivo pharmacokinetic study in order to determine CPD activity against E. coli isolated in UTI cases. Five children (6-10 y) showing E. coli UTI infections received 10 mg/kg/d CPD in a single oral daily dose and were treated up to 10 days, 3 had lower UTI and 2 upper UTI. All patients were clinical and bacteriologically cured. Cultures obtained up to 4 weeks after treatment were negative. CPD serum levels at 2 hours after the first dose of treatment showed a median of 2.7 mg/l (2.3-3.4 range). Bactericidal serum titers at the same time against the patients own strain and an E. coli TEM-1 hyperproducer strain (MIC 4,096 mg/l for ampicillin and 0.5 mg/l for CPD) showed a median value of 1/8 against patients strains and 1/2 against the THP strain.(ABSTRACT TRUNCATED AT 250 WORDS)