Evolução neonatal e aquisição passiva de anticorpos IgG séricos e IgA no colostro reativos com Streptococcus B, anti-LPS de Klebsiella pneumoniae e Pseudomonas aeruginosa em gêmeos

Autor: Monteiro, Renata de Araujo
Jazyk: portugalština
Rok vydání: 2017
Předmět:
Druh dokumentu: Dissertação de Mestrado
Popis: Introdução: Gestações múltiplas apresentam alta morbidade relacionada a fatores como prematuridade, baixo peso ao nascer e sepse. Em gemelares, a aquisição de imunidade passiva por meio do cordão umbilical e do colostro ainda não é bem conhecida. O objetivo geral do estudo foi descrever a concentração de IgG total e específico anti-Streptococcus B, antilipopolissacarídeos de Klebsiella pneumoniae e antilipopolissacarídeos de Pseudomonas aeruginosa no cordão umbilical de recém-nascidos gemelares e a concentração de IgA secretora total e específica destes anticorpos no colostro. O objetivo específico foi analisar a associação entre infecção neonatal e concentração dos anticorpos no sangue de cordão umbilical e no colostro. Métodos: estudo prospectivo transversal de uma coorte de recémnascidos gemelares internados no Centro Neonatal do Instituto da Criança do Hospital das Clínicas da FMUSP no período de 20 meses. Foram excluídos: recém-nascidos com malformação; mães com infecção ou imunodeficiência. Variáveis analisadas: idade gestacional; peso de nascimento; classificação gestacional; concentrações de IgG total e específicos e IgA total e específicas anti-Streptococcus B, antilipopolissacarídeos de Klebsiella pneumoniae e antilipopolissacarídeos de Pseudomonas aeruginosa no sangue de cordão umbilical e no colostro; nutrição enteral; episódios de infecção; desfecho. As dosagens de IgG total foram realizadas por nefelometria e dos demais anticorpos através de ensaio imunoenzimático. Os testes t-Student pareado ou teste de Wilcoxon pareado, teste de Mann-Whitney e teste de Kruskal-Wallis, foram utilizados, considerando-se significante p< 0,005. Resultados: Foram incluídos 57 pares de gêmeos, compondo a casuística de 114 recém-nascidos. A idade gestacional foi 36±1,65 semanas (média±DP) e o peso de nascimento foi 2.304,8 ± 460g (média±DP). As concentrações de anticorpos encontradas foram (média±DP): IgG total 835,71 ± 190,73 mg/dL, IgG anti-Streptococcus B 295,1 ± 250,66 UA/mL, IgG antilipopolissacarídeos de Pseudomonas aeruginosa 280,04 ± 498,66 UA/mL e IgG antilipopolissacarídeos de Klebsiella pneumoniae 504,75 ± 933,93 UA/mL; IgA total 210,2 ± 285,3 g/L, IgA anti-Streptococcus B 6640 ± 9526,8 UA/mL, IgA antilipopolissacarídeos de Pseudomonas aeruginosa 3231,0 ± 2935,2 UA/mL, IgA antilipopolissacarídeos de Klebsiella pneumoniae 3070,1±2886,6 UA/mL. A concentração de IgG total foi menor nos recém-nascidos prematuros (p < 0,001). Em gemelares com idade gestacional < 34 semanas a concentração de IgG total (p=0,013) e IgG antilipopolissacarídeos de Pseudomonas aeruginosa (p=0,032) foi menor. A concentração de anticorpos IgG antilipopolissacarídeos de Klebsiella pneumoniae foi menor nos recém-nascidos pequenos para a idade gestacional (p=0,013). No colostro, houve detecção de IgA total, IgA anti-Streptococcus B, IgA antilipopolissacarídeos de Klebsiella pneumoniae e antilipopolissacarídeos de Pseudomonas aeruginosa em 98,1% das mães. A concentração de IgA antilipopolissacarídeos de Pseudomonas aeruginosa foi menor no colostro das mães de recém-nascidos prematuros (p=0,013). A concentração de IgA antilipopolissacarídeos de Klebsiella pneumoniae foi menor no colostro das mães com parto antes de 34 semanas (p=0,001). Houve infecção em cinco recém-nascidos, cuja concentração de IgG total foi menor (p
Introduction: Multiple pregnancies have high morbidity related to factors such as prematurity, low birth weight and sepsis. In twins, acquisition of passive immunity through the umbilical cord and colostrum is not yet known. The overall aim of the study was to describe the concentration of total and specific IgG antibodies anti-Streptococcus B, anti-lipopolysaccharide of Klebsiella pneumoniae and anti-lipopolysaccharide of Pseudomonas aeruginosa in the umbilical cord of newborn twins and the concentration of total and specific secretory IgA antibodies in the colostrum. The specific aim was to analyze the association between neonatal infection and antibody concentration in the umbilical cord blood and colostrum. Methods: A prospective cross-sectional study of a cohort of newborn twins admitted to the Neonatal Center of Children\'s Institute, University of São Paulo during the period of 20 months. Patients with malformations and mothers with infection or immunodeficiency were excluded from our analysis. Variables analyzed: gestational age; birth weight; sex; gestational classification; antibody concentrations of total and specific IgG and IgA anti-Streptococcus B, anti-lipopolysaccharide of Klebsiella pneumoniae and antilipopolysaccharide of Pseudomonas aeruginosa in umbilical cord blood and colostrum; enteral nutrition; infection episodes; outcome. Total IgG measurements were performed using nephelometry and the specific antibodies were evaluated by enzyme immunoassay. We used paired Student t test or Wilcoxon test, Mann-Whitney test and Kruskal-Wallis test considering significant p < 0.005. Results: During the study period a total of 57 pairs of twins were included, making the sample of 114 newborns. Gestational age was 36 ± 1.65 weeks (mean±SD) and birth weight was 2304.8 ± 460g (mean±SD). We found the following antibody concentrations (mean±SD): total IgG 835.71 ± 190.73 mg/dL, anti-Streptococcus B IgG 250.66 ± 295.1 AU/mL, anti-lipopolysaccharide of Pseudomonas aeruginosa IgG 280.04 ± 498.66 AU/mL and anti-lipopolysaccharide of Klebsiella pneumoniae IgG 504.75±933.93 AU/mL; total IgA 210.2 ± 285.3 g/L, anti- Streptococcus B IgA 6640±9526.8 AU/mL, anti-lipopolysaccharide of Pseudomonas aeruginosa IgA 3231.0±2935.2 AU/mL, antilipopolysaccharide Klebsiella pneumoniae IgA 3070.1±2886.6 AU/mL. The concentration of total IgG was lower in preterm infants (p < 0.001). In twins with gestational age < 34 weeks both total IgG concentration (p = 0.013) and anti-lipopolysaccharide of Pseudomonas aeruginosa IgG concentration (p = 0.032) were lower. The concentration of anti-lipopolysaccharide of Klebsiella pneumoniae IgG was lower in small for gestational age newborns (p=0,013). There was detection of total IgA and specific antibodies in the colostrum of 98.1% mothers. The concentration of anti-lipopolysaccharide of Pseudomonas aeruginosa IgA was lower in the colostrum of premature\'s mothers (p = 0.013). The concentration of anti-lipopolysaccharide of Klebsiella pneumoniae IgA was lower in the colostrum of mothers with delivery before 34 weeks (p = 0.001). Five newborns were diagnosed with sepsis and in this group the concentration of total IgG was lower (p < 0.05). Neonates receiving colostrum had a lower incidence of infection (p < 0.001). Conclusion: This study showed detection of total and specific IgG antibodies in umbilical cord blood for all twin newborn, proving its transplacental passage. There was a significant decrease in the concentration of total IgG antibodies in premature twins and antilipopolysaccharide of Pseudomonas aeruginosa IgG in twins with gestational age less than 34 weeks. There was detection of total and specific IgA in the colostrum of 98.1% mothers. The concentration of anti-lipopolysaccharide of Pseudomonas aeruginosa IgA was lower in mothers of premature twins. Among the newborns with gestational age less than 34 weeks there was a decrease in the concentration of anti-lipopolysaccharide Klebsiella pneumoniae IgA, suggesting that prematurity may have influenced the transfer of maternal antibodies through colostrum. The highest incidence of infection in the newborn group who did not receive colostrum and in those who had significantly lower total IgG serum antibodies reinforces the importance of anti-infectious protection afforded by passive immunity transferred from the mother
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