Assuntos
Eritromicina/uso terapêutico , Recém-Nascido Prematuro/microbiologia , Infecções por Ureaplasma/tratamento farmacológico , Ureaplasma urealyticum/isolamento & purificação , Interpretação Estatística de Dados , Humanos , Recém-Nascido de Baixo Peso/microbiologia , Recém-Nascido , Viés de Seleção , Traqueia/microbiologiaRESUMO
Incomplete transfer of maternal antibodies specific to respiratory syncytial virus (RSV) has been suggested as an explanation for the increased risk of RSV infections in preterm infants. Antibodies directed against the two major RSV envelope glycoproteins, F and G, are protective in vitro and in vivo. Our study was conducted to measure IgG, IgG1, IgG2, and IgG3 antibody titers against the RSV F and G glycoproteins in cord sera from infants born at different gestational ages. Titers of neutralizing antibody were measured in a subset of the subjects. The mean (+/- SEM) log2 titers of IgG antibodies directed against the RSV F and G glycoproteins were significantly lower in infants born at < or = 28 weeks of gestation (11.2 and 10.8 for F and G glycoproteins, respectively) than in term infants (12.6 and 12.8 for F and G, respectively) (p < 0.05). Preterm infants born at > or = 29 weeks had titers of antibodies against the F glycoprotein comparable to those of term infants. The highest titers of RSV-specific antibodies were in the IgG1 and IgG2 subclasses. Mean (+/- SEM) neutralizing antibody titers were lower in infants born at < or = 28 weeks (7.7 +/- 0.4) than in term infants (10.2 +/- 0.3) (p < 0.001). We conclude that (1) RSV-specific antibody titers were lower than in term infants only in the most premature infants (< or = 28 weeks) and (2) preterm infants born at > or = 29 or > or = 33 weeks of gestation had RSV-specific titers against F and G glycoproteins, respectively, that were comparable to those of term infants. Preterm infants born at < or = 28 weeks could represent a target population for passive immunoprophylaxis.
Assuntos
Anticorpos Antivirais/sangue , Imunoglobulina G/sangue , Recém-Nascido Prematuro/imunologia , Vírus Sinciciais Respiratórios/imunologia , Estudos de Casos e Controles , Glicoproteínas/imunologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro/microbiologiaRESUMO
We compared the presence and identities of isolates from blood culture samples obtained by percutaneous venipuncture with those of commensal skin organisms cultured from respective venipuncture sites after skin cleansing; 677 blood and skin site culture pairs from 488 infants were compared. Organisms grew in 58 blood cultures; nine of these cultures had corresponding venipuncture site cultures that also grew organisms. Forty-two blood culture isolates were coagulase-negative staphylococci; five of these were associated with similar venipuncture site cultures. According to restriction-endonuclease fingerprinting of chromosomal DNA and plasmid analysis, three pairs of blood and venipuncture site cultures were identical and two pairs were different. Thus only 7% (3/42) of coagulase-negative staphylococcal blood isolates were associated with identical contamination at the venipuncture site. We conclude that, if the venipuncture site has been carefully cleansed, the growth of coagulase-negative staphylococci in blood cultures of specimens from premature neonates indicates bacteremia rather than skin contamination in the vast majority of cases.
Assuntos
Bacteriemia/microbiologia , Bactérias/isolamento & purificação , Sangria , Recém-Nascido Prematuro/microbiologia , Pele/microbiologia , Bactérias/classificação , Coleta de Amostras Sanguíneas , Impressões Digitais de DNA , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Hospitalização , Humanos , Recém-Nascido , Estudos Prospectivos , Manejo de Espécimes , Staphylococcus/classificação , Staphylococcus/isolamento & purificaçãoRESUMO
Se describen 4 casos de infección diseminada por Candida albicans, en prematuros de entre 26 y 33 semanas de gestación, y entre 760 y 2.580 g de peso al nacer, inclusive. Todos presentaron signos clínicos de insuficiencia respiratoria y de septicemia. La necropsia demostró en todos ellos signos anatomopatológicos de hipoxia intensa, y en 3 casos evidencias morfológicas que indican a la mucosa gastrointestinal como puerta de entrada y diseminación micótica. La distribución de los organos comprometidos y la reacción inflamatoria tisular es semejante a la descrita en adultos, con y sin granulocitopenia
Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Candida albicans/patogenicidade , Candidíase/congênito , Recém-Nascido Prematuro/microbiologia , Recém-Nascido de Baixo Peso/microbiologiaRESUMO
To follow the emergence of surface colonization with coagulase-negative staphylococci in neonates, we sampled four surface sites (axilla, ear, nasopharynx, and rectum) in 18 premature infants during the first 4 weeks of life. Swabs were obtained on the first day of life, twice weekly for 2 weeks, and weekly thereafter. Isolates were characterized by species, biotype, antibiotic susceptibility patterns, and slime production. Over 4 weeks the percentage of infants with Staphylococcus epidermidis as the only surface coagulase-negative staphylococci rose from 11% to 100%. Predominance of a single S. epidermidis biotype increased from none to 89%. Multiple antibiotic resistance rose from 32% to 82% of isolates, and the prevalence of slime production increased from 68% to 95%. This microbiologic pattern was established by the end of the first week of life and persisted throughout the month of study. In three infants, S. epidermidis sepsis developed with organisms identical to their predominant surface isolate. We conclude that species, multiple antibiotic resistance, and slime production appear to confer a selective advantage for the surface colonization of premature newborn infants in the intensive care nursery environment. Infants so colonized may be at greater risk for subsequent infection with these strains of coagulase-negative staphylococci.