Amélia Miyashiro Nunes dos Santos

Strong HIV-1-specific T cell responses in HIV-1-exposed uninfected infants and neonates revealed after regulatory T cell removal.

Background In utero transmission of HIV-1 occurs on average in only 3%–15% of HIV-1-exposed neonates born to mothers not on antiretroviral drug therapy. Thus, despite potential exposure, the majority of infants remain uninfected. Weak HIV-1-specific T-cell responses have been detected in children exposed to HIV-1, and potentially contribute to protection against infection. We, and others, have recently shown that the removal of CD4+CD25+ T-regulatory (Treg) cells can reveal strong HIV-1 specific T-cell responses in some HIV-1 infected adults. Here, we hypothesized that Treg cells could suppress HIV-1-specific immune responses in young children. Methodology/Principal Findings We studied two cohorts of children. The first group included HIV-1-exposed-uninfected (EU) as well as unexposed (UNEX) neonates. The second group comprised HIV-1-infected and HIV-1-EU children. We quantified the frequency of Treg cells, T-cell activation, and cell-mediated immune responses. We detected high levels of CD4+CD25+CD127− Treg cells and low levels of CD4+ and CD8+ T cell activation in the cord blood of the EU neonates. We observed HIV-1-specific T cell immune responses in all of the children exposed to the virus. These T-cell responses were not seen in the cord blood of control HIV-1 unexposed neonates. Moreover, the depletion of CD4+CD25+ Treg cells from the cord blood of EU newborns strikingly augmented both CD4+ and CD8+ HIV-1-specific immune responses. Conclusions/Significance This study provides new evidence that EU infants can mount strong HIV-1-specific T cell responses, and that in utero CD4+CD25+ T-regulatory cells may be contributing to the lack of vertical transmission by reducing T cell activation.

Red Blood Cell Transfusions are Independently Associated with Intra-Hospital Mortality in Very Low Birth Weight Preterm Infants

OBJECTIVE To test the hypothesis that red blood cell (RBC) transfusions in preterm infants are associated with increased intra-hospital mortality. STUDY DESIGN Variables associated with death were studied with Cox regression analysis in a prospective cohort of preterm infants with birth weight <1500 g in the Brazilian Network on Neonatal Research. Intra-hospital death and death after 28 days of life were analyzed as dependent variables. Independent variables were infant demographic and clinical characteristics and RBC transfusions. RESULTS Of 1077 infants, 574 (53.3%) received at least one RBC transfusion during the hospital stay. The mean number of transfusions per infant was 3.3 ± 3.4, with 2.1 ± 2.1 in the first 28 days of life. Intra-hospital death occurred in 299 neonates (27.8%), and 60 infants (5.6%) died after 28 days of life. After adjusting for confounders, the relative risk of death during hospital stay was 1.49 in infants who received at least one RBC transfusion in the first 28 days of life, compared with infants who did not receive a transfusion. The risk of death after 28 days of life was 1.89 times higher in infants who received more than two RBC transfusions during their hospital stay, compared with infants who received one or two transfusions. CONCLUSION Transfusion was associated with increased death, and transfusion guidelines should consider risks and benefits of transfusion.

Validity of behavioral and physiologic parameters for acute pain assessment of term newborn infants

CONTEXT The subjectivity of pain causes enormous difficulties in evaluating neonatal pain with a single, practical and easy-to-apply tool. Pain evaluation in the neonatal period should be performed by valid, safe, useful and feasible methods. OBJECTIVE To evaluate the validity of the Neonatal Facial Coding System (NFCS), Neonatal Infant Pain Scale (NIPS), heart rate (HR) and O2 saturation (O2 sat) for neonatal pain assessment. DESIGN Prospective, double-blind randomized trial. SETTING A secondary level maternity hospital. PARTICIPANTS 70 healthy neonates requiring bilirubin dosage were randomly assigned to receive a venous puncture (P: n = 33, BW 3.2 kg, SD 0.6; GA 39 wk, SD 1; 59 h of life, SD 25) or an alcohol swab friction (F: n = 37; BW 3.1 kg, SD 0.5; GA 39 wk, SD 1; 52 h of life, SD 17). INTERVENTION All measurements were taken prior to (PRE), during (TO), and 1 (T1), 3(T3), 5(T5) and 10(T10) minutes after the procedure. MEASUREMENTS A neonatologist evaluated NFCS, NIPS, HR and O2 sat by pulse oxymetry. RESULTS Median NFCS and NIPS results at T0, T1 and T3 were higher in P group, compared to F. More P neonates presented NFCS > 2 and/or NIPS > 3 at T0, T1 and T3. HR was lower in P group at T1. Average O2 sat was above 90% during the whole study period in both groups. CONCLUSION NFCS and NIPS are suitable instruments for neonatal pain evaluation. Heart rate and O2 saturation can be used only as auxiliary methods.

Disagreement between parents and health professionals regarding pain intensity in critically ill neonates

OBJECTIVE To verify whether parents and health professionals homogeneously evaluate presence and intensity of neonatal pain. METHODS This cross-sectional study enrolled 52 neonates and 154 adults. Inclusion criteria for neonates were admission to neonatal intensive care unit, presence of gastric tube, tracheal tube, and venous lines. Each newborn was observed by a different group of three adults (parent, nurse assistant and pediatrician) for 1 minute at the same time to evaluate presence and intensity of infants pain. Homogeneity of pain evaluation was analyzed by a modified Bland-Altman plot and by intraclass correlation coefficient (ICC). Multiple linear regression analysis was used to evaluate association of neonatal characteristics and heterogeneity of pain scores for adults. RESULTS ICC showed disagreement of the pain scores given by the three groups of adults (ICC 0.066, agreement > 0.75). Bland-Altman analysis showed agreement among adults when they thought pain was absent. When they thought pain was present, there was heterogeneity of opinions regarding intensity of neonatal pain. Multiple regression analysis indicated that 10% of this disagreement could be explained by infants gender and mode of delivery. CONCLUSIONS Disagreement among adults about intensity of neonatal pain is a marker of the difficulty in deciding the need for analgesia in preverbal patients.

Variability on red blood cell transfusion practices among Brazilian neonatal intensive care units

BACKGROUND: Guidelines for red blood cell (RBC) transfusions exist; however, transfusion practices vary among centers. This study aimed to analyze transfusion practices and the impact of patients and institutional characteristics on the indications of RBC transfusions in preterm infants.

Neurodevelopmental assessment of very low birth weight preterm infants at corrected age of 18-24 months by Bayley III scales

OBJECTIVE To evaluate the prevalence of delay and factors associated with neurodevelopmental scores in premature infants. METHODS Cross-sectional study to assess the development by Bayley Scales III, including very low birth weight preterm infants aged 18 to 24 months who were under follow-up at the outpatient clinic for preterm infants. Congenital malformation, genetic syndrome, symptomatic congenital infection at birth, deafness, and blindness were excluded. Numerical variables were compared by Mann-Whitney or Student t test and categorical variables by chi-square or Fishers exact test. Factors associated with developmental scores were analyzed by linear regression, and statistical significance level was established at p < 0.05. RESULTS Out of the 58 children included, four (6.9%) presented cognitive delay, four (6.9%) motor, 17 (29.3%) language, 16 (27.6%) social-emotional and 22 (37.0%) adaptive-behavior delay. By multiple linear regression, the variables: social classes CDE (-13.27; 95%CI: -21.23 to -5.31), oxygen dependency at 36 weeks of corrected age (-8.75; 95%CI: -17.10 to -0.39) decreased the cognitive developmental score. Periventricular leukomalacia decreased the cognitive (-15.21; 95%CI: -27.61 to -2.81), motor (-10.67; 95%CI:-19.74 to -1.59) and adaptive-behavior scores (-21.52; 95%CI: -35.60 to -7.44). The female sex was associated with higher motor (10.67; 95%CI: 2.77 to 12.97), language (15.74; 95%CI: 7.39 to 24.09) and social-emotional developmental scores (10.27; 95%CI: 1.08 to 19.46). CONCLUSIONS Very low birth weight preterm infants aged from 18 to 24 months of corrected age presented more frequently language, social-emotional and adaptive-behavior delays. The variables: social classes CDE, periventricular leukomalacia, bronchopulmonary dysplasia and male sex reduced the neurodevelopmental scores.

Screening for inborn errors of metabolism among newborns with metabolic disturbance and/or neurological manifestations without determined cause

CONTEXT Inborn Errors of Metabolism are hereditary affections resulting from incompetence in enzymatic reactions of intermediary metabolism. At present, several hundred hereditary metabolic disturbances are known, many of which correspond to severe life-threatening disorders. OBJECTIVE The early detection of carriers has motivated the screening for these disturbances among newborns at the Neonatal Unit of Hospital São Paulo, in an attempt to initiate support treatment, when available, before clinical manifestations become evident. DESIGN Prospective study of risk patients. SETTING Laboratory for Inborn Errors of Metabolism at the Center for Medical Genetics of the Departments of Pediatrics and Morphology of Universidade Federal de São Paulo/Escola Paulista de Medicina. Newborn care unit at a tertiary care hospital. PARTICIPANTS 101 children admitted into the Neonatal Unit were included in this study by presenting hypoglycemia, metabolic acidosis, jaundice, difficulty in gaining weight, diarrhea, vomiting, hepato- and/or splenomegaly, cataracts, apnea, convulsions, hypo- or hypertonia. DIAGNOSTIC TESTS Tests routinely utilized, performed for qualitative research of abnormal substances excreted in the urine in situations of metabolic disorder. RESULTS Children were included in the study mainly because of presenting hypoglycemia, jaundice and metabolic acidosis. Sixty-four newborns presented at least one positive test result. Most of the positivity was due to transitory metabolic alterations of the newborn, such as the case of Transitory Neonatal Tyrosinemia, presented by 29 patients. Nine infants were referred to the Center for Medical Genetics of Universidade Federal de São Paulo for continuation of the diagnostic investigation. For three of them, the tests applied permitted us to formulate a diagnostic hypothesis of mucopolysaccharidosis, tyrosinemia type I and non-ketotic hyperglycinemia, respectively. CONCLUSIONS The high positivity observed in the tests reflects the newborns own metabolic immaturity. The selection of 9% of the studied cases for outpatient follow-up confirms that Inborn Errors of Metabolism must be suspected whenever a patient presents metabolic disturbances or neurological manifestations without a determined cause. They should be researched in parallel with the other diagnostic possibilities and not just taken to be exceptional diagnoses.

Multidimensional pain assessment of preterm newborns at the 1st, 3rd and 7th days of life

CONTEXT AND OBJECTIVE It is challenge to assess and treat pain in premature infants. The objective of this study was to compare the multidimensional pain assessment of preterm neonates subjected to an acute pain stimulus at 24 hours, 72 hours and seven days of life. DESIGN AND SETTING Prospective cohort study, at Universidade Federal de São Paulo. METHODS Eleven neonates with gestational age less than 37 weeks that needed venepuncture for blood collection were studied. The exclusion criteria were Apgar score < 7 at five minutes, presence of any central nervous system abnormality, and discharge or death before seven days of life. Venepuncture was performed in the dorsum of the hand, and the heart rate, oxygen saturation and pain scales [Neonatal Facial Coding System (NFCS), Neonatal Infant Pain Scale (NIPS), and Premature Infant Pain Profile (PIPP)] were assessed at 24 hours, 72 hours and 7 days of life. NFCS and NIPS were evaluated prior to procedure (Tpre), during venepuncture (T0), and two (T2) and five (T5) minutes after needle withdrawal. Heart rate, O2 saturation and PIPP were measured at Tpre and T0. Mean values were compared by repeated-measurement analysis of variance. RESULTS The pain parameters did not differ at 24 hours, 72 hours and 7 days of life: heart rate (p = 0.22), oxygen saturation (p = 0.69), NFCS (p = 0.40), NIPS (p = 0.32) and PIPP (p = 0.56). CONCLUSION Homogeneous pain scores were observed following venepuncture in premature infants during their first week of life.

Factors associated with clinical complications during intra-hospital transports in a neonatal unit in Brazil.

OBJECTIVE Analyze factors associated with clinical complications during intra-hospital transport of neonatal intensive care unit (NICU) patients. METHODS Prospective study of 641 infants submitted to 1197 intra-hospital transports at a public university NICU. Factors associated with clinical complications during intra-hospital transports were studied by multiple logistic regression analysis. RESULTS Included infants had a mean gestational age of 35.1 ± 3.8 weeks and a birth weight of 2328 ± 906 g. Underline diseases were: malformations (71.9%), infections (7.6%), respiratory distress (4.1%) and others (16.4%). Patients were transported for surgical procedures (22.6%), magnetic resonance (10.6%), tomography imaging (20.9%), contrasted exams (18.2%), ultrasound (10.4%) and others (17.3%). Clinical complications occurred in 327 (27.3%) transports and were associated (odds ratio; 95% CI) with: central nervous system malformations (1.6; 95% CI 1.0-2.0); use of supplemental oxygen (4.0; 95% CI 2.8-5.6); mechanical ventilation (5.0; 95% CI 3.5-7.5); transport for surgeries (4.0; 95% CI 1.1-14.0) and duration of the transport longer than 120 min (1.6; 95% CI 1.1-2.4). CONCLUSIONS Intra-hospital transports are associated with increased risk of clinical complications.

Neonatal screening for severe combined immunodeficiency in Brazil

OBJECTIVE To apply, in Brazil, the T-cell receptor excision circles (TRECs) quantification technique using real-time polymerase chain reaction in newborn screening for severe combined immunodeficiency and assess the feasibility of implementing it on a large scale in Brazil. METHODS 8715 newborn blood samples were collected on filter paper and, after DNA elution, TRECs were quantified by real-time polymerase chain reaction. The cutoff value to determine whether a sample was abnormal was determined by ROC curve analysis, using SSPS. RESULTS The concentration of TRECs in 8,682 samples ranged from 2 to 2,181TRECs/μL of blood, with mean and median of 324 and 259TRECs/μL, respectively. Forty-nine (0.56%) samples were below the cutoff (30TRECs/μL) and were reanalyzed. Four (0.05%) samples had abnormal results (between 16 and 29TRECs/μL). Samples from patients previously identified as having severe combined immunodeficiency or DiGeorge syndrome were used to validate the assay and all of them showed TRECs below the cutoff. Preterm infants had lower levels of TRECs than full-term neonates. The ROC curve showed a cutoff of 26TRECs/μL, with 100% sensitivity for detecting severe combined immunodeficiency. Using this value, retest and referral rates were 0.43% (37 samples) and 0.03% (3 samples), respectively. CONCLUSION The technique is reliable and can be applied on a large scale after the training of technical teams throughout Brazil.