Longitudinal neurodevelopmental and neuromotor outcome in congenital diaphragmatic hernia patients in the first 3 years of life.

OBJECTIVE: The objective of this study was to longitudinally evaluate the neurodevelopmental (ND) outcome in congenital diaphragmatic hernia (CDH) survivors during the first 3 years of life. STUDY DESIGN: The study cohort consists of 47 CDH survivors that were enrolled in our prospective, follow-up program between July 2004 and September 2010, and underwent serial ND evaluations during the first 3 years of life. ND outcomes were evaluated using the Bayley Scales of Infant Development (BSID)-II or BSID-III. Persistent ND impairment was defined as a score that remained 79 for the cognitive, language and psychomotor domains at the most recent follow-up visit compared with the first assessment. RESULT: The median age at first and last evaluation was 8 (range, 5 to 15) and 29 (range, 23 to 36) months, respectively. During the follow-up, ND scores improved to average in 17%, remained average in 60%, remained delayed in 10%, improved from severely delayed to mildly delayed in 2% and deteriorated from average to delayed in 15%. Motor scores improved to average in 26%, remained average in 55%, remained delayed in 8% and improved from severely delayed to mildly delayed in 11%. Intrathoracic liver position (P=0.004), preterm delivery (P=0.03), supplemental O2 requirement at day of life 30 (P=0.007), age at discharge (P=0.03), periventricular leukomalacia (PVL; P=0.004) and initial neuromuscular hypotonicity (P=0.01) were associated with persistent motor delays. No relationship was found between patient's characteristics and the risk of persistent cognitive and language delays. CONCLUSION: (1) The majority of children with CDH are functioning in the average range by early preschool age, (2) most children who had early delays showed improvement in their ND outcome, (3) children showing delays in all the three domains were the least likely to show improvement and (4) CDH severity appears to be predictive of persistent psychomotor delays.

Developmental follow-up of breastfed term and near-term infants with marked hyperbilirubinemia.

OBJECTIVE: In recent years, the increased prevalence of breastfeeding in conjunction with early discharge practices has increased the risk for marked hyperbilirubinemia in neonates. This has resulted in the potential for bilirubin brain injury in affected infants. The purpose of this study was to identify all infants >/=36 weeks' gestational age with bilirubin levels >25 mg/dL and evaluate them for early and late evidence of bilirubin brain injury. METHODS: We reviewed the charts of all infants (from 1993-1996) >/=36 weeks' gestational age who were readmitted to the hospital during the first week of life with bilirubin levels >25 mg/dL. Readmission records were reviewed for early signs of bilirubin encephalopathy. Magnetic resonance imaging (MRIs) and Brainstem auditory-evoked responses (BAERs) were reviewed for evidence of bilirubin toxicity. At follow-up, study infants had a complete neurodevelopmental examination, repeat MRIs, and behavioral hearing evaluations. RESULTS: From 1993 to 1996, we identified 6 term and near-term infants readmitted to the hospital within the first week of life with peak bilirubin values ranging from 26.4 mg/dL (451 micromol/L) to 36.9 mg/dL (631 micromol/L). Five of 6 infants had bilirubin values >30 mg/dL (513 micromol/L). All were exclusively breastfed or fed a combination of breast and bottle feedings. Five of 6 infants presented with abnormal neurologic signs. Four infants had initial MRIs, 3 of whom had increased signal intensity in the basal ganglia consistent with kernicterus. Two infants had abnormal BAERs; both also had abnormal MRIs. Five of 6 infants received exchange transfusions and all were treated with phototherapy and intravenous fluids. Follow-up examinations between 3 months and 2 years showed resolution of clinical signs in all but 1 infant. Four infants had a subsequent normal MRI and 1 had residual hearing impairment. One infant demonstrated severely abnormal developmental evaluations, as well as both an abnormal initial MRI and BAERs. Follow-up MRI showed evidence of encephalomalacia with changes not characteristic of kernicterus. CONCLUSIONS: We observed transient neurologic abnormalities in 5 of 6 infants readmitted to the hospital during the first week of life with marked hyperbilirubinemia. The abnormalities resolved following aggressive management using hydration, phototherapy, and exchange transfusion and may not correlate with long-term prognosis. Less aggressive therapy may be associated with residual neurologic abnormalities. We speculate that inadequate establishment of breastfeeding coupled with early discharge practices may play a role in the development of marked hyperbilirubinemia in these infants.

Pulmonary hypertension in children following extracorporeal membrane oxygenation therapy and repair of congenital diaphragmatic hernia.

OBJECTIVE: Pulmonary hypertension (PHT) is present in all children at birth, but its degree and rate of resolution in infants diagnosed with congenital diaphragmatic hernia (CDH) requiring extracorporeal membrane oxygenation (ECMO) need to be established. STUDY DESIGN: Twenty-one ECMO/CDH survivors (aged 3.2 +/- 1.4 years) were prospectively evaluated by Doppler echocardiography (ECHO) to determine the presence of PHT. Twenty children without structural heart disease were used as controls. Study patients received a physical examination and an electrocardiograph examination, and their charts were reviewed for neonatal course data. Patients found to have PHT by ECHO received a complete history and exercise treadmill/oxygen desaturation study. RESULTS: Eight of the 21 patients (38%) met echocardiographic criteria for PHT. No neonatal course data were found to be predictive of eventual PHT status. There was no correlation between physical examination or electrocardiographic findings and PHT. Complete histories showed five of the eight patients with PHT had some degree of exercise intolerance and seven had wheezing. Two of the seven patients studied on the treadmill desaturated 5% or greater from baseline. CONCLUSION: There is evidence that PHT either persists or recurs in a significant portion of the ECMO/CDH population and may remain symptomatic well beyond the neonatal period.

Propagation and characterization of human herpesvirus-7 (HHV-7) isolates in a continuous T-lymphoblastoid cell line (SupT1).

After initial culture of HHV-7 in PHA-stimulated human cord blood mononuclear cells (HCBMC), six HHV-7 isolates were propagated successfully in an immature continuous T-lymphoblastoid cell line SupT1. All six isolates infected efficiently the SupT1 cells, and the infected cells became grossly enlarged and multinucleated 7-21 days post-infection. Various stages of HHV-7 morphogenesis were detected. Cell-free supernatants from HHV-7-infected SupT1 cells were infectious to HCBMC as well as to SupT1 cells. The HHV-7-infected SupT1 and HCBMC cell lysates contained more infectious virus than the centrifuged cell culture fluid supernates from the same culture. The HHV-7 isolates H7-2, H7-3, JHC, and JB, concentrated 500 times, had average infectivity titers of 10(3.0) TCID50/ml while strains H7-4 and KHR titered approximately 1-2 logs higher. When all six HHV-7 isolates were propagated in SupT1 and culture fluid supernatants were examined 14-21 days post-infection by negative stain electron microscopy they contained an average of 1.9 x 10(9) virus particles/liter. IFA and ELISA, using HHV-7/SupT1 cell lysate as an antigen, seem to correlate well in detecting high and low HHV-7 antibody in sera from chronic fatigue patients and healthy donors as controls. HHV-7 from SupT1 cell culture was free of HHV-6 and other human herpesviruses as tested by PCR, and the HHV-7 PCR signal was still strong when the viral preparation was diluted to 4.82 x 10(2) genome copies. Since HCBMC are expensive to obtain and available in only small amounts, it is difficult to obtain large quantities of HHV-7 antigen. On the other hand, the SupT1 cell is an excellent source to produce consistently sufficient quantities of HHV-7 for purification studies, development of immunodiagnostics, in vivo infectivity studies, evaluation of antiviral drugs, and molecular biological studies.

Follow-up care of the low birth weight infant.

Care of the preterm infant after discharge is a challenge for the pediatric follow-up team. All premature infants should be followed through infancy and into preschool and school years because of the common ongoing medical concerns and the high risk of developmental disabilities. Although impossible to predict with great accuracy in the neonatal period, it is appropriate to select those preterm infants who have the highest risk for disabilities and provide to them a closer degree of surveillance.

Results at age 8 years of early intervention for low-birth-weight premature infants. The Infant Health and Development Program.

OBJECTIVE: To reevaluate at age 8 years children who had participated during the first 3 years of life in a randomized clinical trial of special services for low-birthweight (LBW) premature infants. DESIGN: Follow-up of a randomized controlled trial of premature infants (< or = 37 weeks' gestation), stratified by 2 LBW groups (lighter [< or = 2000 g] and heavier [2001-2500 g]) and divided into intervention (n=377) and follow-up only (n=608) groups. SETTING: Eight sites serving diverse populations. PARTICIPANTS: At age 8 years, 874 children were assessed: 336 in the intervention group and 538 in the follow-up only group. INTERVENTION: The 3-year intervention consisted of home visits (birth to 3 years), child development center services (ages 1 to 3 years), and parent group meetings (ages 1 to 3 years). PRIMARY OUTCOME MEASURES: Cognitive functioning (Weschler Intelligence Scale for Children-III; Peabody Picture Vocabulary Test-Revised); academic achievement (Woodcock-Johnson Tests of Achievement-Revised); and parental reports of school performance, behavior (Child Behavior Checklist), and health (Child General Health Survey). RESULTS: At age 8 years, in the entire cohort and in the lighter LBW stratum, the intervention and follow-up only groups were similar on all primary outcome measures. Differences favoring the intervention group were found within the heavier LBW group: full-scale IQ score (4.4 points higher, P=.007), verbal IQ score (4.2 points higher, P=.01), performance IQ score (3.9 points higher, P=.02), mathematics achievement score (4.8 points higher, P=.04), and receptive vocabulary score (6.7 points higher, P=.001). On a physical functioning subscale, the whole intervention group received less favorable ratings, while the lighter LBW intervention group had lower maternal ratings assessing social limitations caused by behavior. CONCLUSION: Although at age 8 years there were modest intervention-related differences in the cognitive and academic skills of heavier LBW premature children, attenuation of the large favorable effects seen at 3 years was observed in both the heavier and lighter LBW groups. This indicates a need to develop additional intervention strategies for LBW premature children that can provide sustained benefits.

Effects of sweet taste stimulation on growth and sucking in preterm infants.

OBJECTIVE: To evaluate the effect of sweet taste stimulation in augmenting the reported growth-enhancing effects of nonnutritive sucking in preterm infants who are gavage-fed. DESIGN: Random assignment of preterm infants to receive stimulation by one of three methods during each feeding until totally orally fed. SETTING: Hospital intensive-care and infant transitional units. PATIENTS: Eligibility criteria included body weight greater than or equal to 1,250 g, gestational age younger than 34 weeks, growth parameters appropriate for gestational age, tolerating at least 100 kcals/kg/day by gavage feeding with evidence of weight gain, and no clinical evidence of health complications. Data are presented for 42 infants who completed 14 days of treatment. INTERVENTIONS: Exposure to a sweet pacifier, a latex pacifier, or maternal heartbeat sounds during gavage feedings. MAIN OUTCOME MEASURES: Growth, time to total oral feeding, and sucking responses. RESULTS: No significant differences in sucking measures were noted among treatment groups. Differences in progression time to total oral feedings and weight gain favored the sweet-pacifier group but were not statistically significant. CONCLUSIONS: Oral stimulation of gavage-fed, preterm infants during a 2-week hospitalization was not sufficient to elicit a significant improvement in growth efficiency, progression to total oral feedings, or sucking maturation. Additional studies may show a beneficial effect of chemosensory stimulation in preterm infants.

Survivors of extracorporeal membrane oxygenation at 1 year of age: the relationship of primary diagnosis with health and neurodevelopmental sequelae.

OBJECTIVE: Although extracorporeal membrane oxygenation (ECMO) has been responsible for the improved survival of infants with cardiorespiratory failure, its use over the last decade has raised concern as to the health of the survivors and the severity of neurodevelopmental sequelae. Though infants meeting ECMO criteria have a variety of reasons prompting the use of this therapy, most studies to date have simply reported outcome on the entire population that has survived without regard to the original nature of the child's illness. The purpose of this study was to determine the type and extent of health-related problems and neurodevelopmental sequelae in infants requiring ECMO therapy and the association of these findings with the infants' primary diagnosis. METHODS: Eighty-two neonates required ECMO therapy between May 1990 and December 1993. The most common diagnosis prompting ECMO therapy included 26% with meconium aspiration syndrome, 34% with congenital diaphragmatic hernia (CDH), 16% with persistence of the fetal circulation, and 9% with sepsis. Information concerning the hospital course was obtained through chart review, and the infants were seen at 6 and 12 months of age for medical and neurodevelopmental follow-up. Data were analyzed using descriptive statistics and Fisher's exact test, t-tests, and analysis of variance where appropriate. Assessment of hospital course and discharge data focused on the four main diagnostic groups, whereas follow-up data were further limited to the two most frequently encountered groups (meconium aspiration syndrome and CDH). RESULTS: Overall survival was 79%. Significant differences in survival were noted based on primary diagnostic category. Those with CDH fared the worst, with an overall survival rate of 68% and a more complicated hospital course with a longer duration of ECMO. At discharge, the CDH group demonstrated a greater incidence of bronchopulmonary dysplasia, gastroesophageal reflux, feeding dysfunction, and hypotonia. No significant differences were noted in the incidence of intraventricular hemorrhage, cerebral infarction, extra-axial fluid collection, or seizures. Hearing loss was uncommon. During the first year of life, although no differences were noted in growth rate, infants in the CDH group continued to experience a higher incidence of gastroesophageal reflux (43%) and feeding dysfunction, with 36% of this group requiring tube feedings for nourishment. Although 40% of the entire ECMO population was diagnosed with bronchopulmonary dysplasia before initial discharge, by 1 year of age, 50% of those with CDH versus 17% of those with meconium aspiration syndrome continued to be clinically symptomatic. Although the ECMO population as a whole scored in the normal range developmentally, CDH infants had significantly lower motor and slightly lower cognitive scores at 1 year of age. Despite finding abnormal muscle tone in a high percentage of the entire ECMO population at discharge, most demonstrated resolution by 1 year of age. Of the CDH infants, however, 75% continued to evidence some degree of hypotonicity, which affected acquisition and quality of gross motor skills. CONCLUSION: Despite the impact that ECMO has had on the survival of infants with severe respiratory failure, the efficacy of ECMO cannot be assessed accurately without an analysis of the extent and morbidity in the surviving population. Most centers are reporting relatively low morbidity for the entire ECMO population. However, upon separating this population into primary diagnostic categories, we found that the CDH population encountered a greater number of neurodevelopmental, respiratory, and feeding abnormalities during the first year of life. The reasons for these differences are unclear but may be related to the severity of the primary illness itself or the variables associated with prolonged ECMO therapy. Stratifying outcome by primary diagnosis gives the health care provider more information to improve

Human herpesvirus 6 as a potential copathogen.

The molecular, biological and immunological studies of the recently identified human herpesvirus 6 (HHV-6) suggest that the virus is involved in the etiology of at least three lymphoproliferative diseases. Furthermore, HHV-6 may be an important cofactor in the pathogenesis of several other diseases, including HIV-associated disease and some cancers, but further investigation is needed to establish a causal relationship.

MRI, MRA, and neurodevelopmental outcome following neonatal ECMO.

Cranial magnetic resonance imaging (MRI) of 31 newborn infants treated with venoarterial cardiopulmonary bypass for severe but reversible respiratory failure, revealed major focal parenchymal lesions in 7 of 31 infants (23%) and demonstrated abnormal enlargement of extra-axial and ventricular cerebrospinal fluid spaces in 16 of 31 (51%). No preferential left versus right lateralization of focal injury was observed in conjunction with right common carotid artery and jugular vein ligation. No statistically significant relationships were found between major brain lesions on MRI scans and the clinical characteristics of the pre-extracorporeal membrane oxygenation (ECMO), ECMO, and post-ECMO course. Major focal brain lesions were significantly associated with an asymmetric cerebrovascular response to carotid ligation of the right versus left middle cerebral arteries as detected by magnetic resonance angiography (P < .05). Enlarged cerebrospinal fluid spaces were not significantly related to the presence of parenchymal MRI lesions, but were associated with lower Bayley neurodevelopmental scores for mental (MDI) and psychomotor evaluations (PDI) at 6 and 12 months (P < .05). It is concluded that asymmetries of cerebral vascular adaptation detected by magnetic resonance angiography after ECMO may be associated with major brain lesions revealed by MRI. Thereafter, the presence of enlarged cerebrospinal fluid spaces on MRI is associated with a poor shortterm developmental outcome.

Outcome for infants with congenital diaphragmatic hernia requiring extracorporeal membrane oxygenation: the first year.

Congenital diaphragmatic hernia (CDH) has been associated with a high mortality rate. The purposes of this study were to determine the impact of extracorporeal membrane oxygenation (ECMO) on the survival of infants with CDH and to document the sequelae and 1-year neurodevelopmental outcome for CDH infants who required ECMO. Thirty neonates with CDH were admitted between May 7, 1990 and October 1, 1992. Twenty required ECMO and were enrolled in our neonatal follow-up program. Information about the infants' neonatal course was obtained from chart review, and the infants were seen at 3, 6, and 12 months of age for medical and neurodevelopmental follow-up. Primary diaphragmatic repair was performed in 13 infants. Five required Goretex graft reconstruction (GGR), and two did not have repair. Sixteen (80%) of the 20 infants who required ECMO survived. The overall survival rate increased from 31% (10 of 32) in the 5 years previous to the start of the ECMO program to 63% (19 of 30) since then (P = .01). The most common sequelae noted by the time of discharge included gastroesophageal reflux (GER; 81%), the need for tube feeding (69%), and chronic lung disease (CLD; 62%). At 1 year of age, mean cognitive skills were average (87 +/- 23) and motor skills were borderline (75 +/- 24) according to the Bayley Scales of Infant Development. Hypotonia was present in 10 of 13 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Early intervention in low-birth-weight premature infants. Results through age 5 years from the Infant Health and Development Program.

OBJECTIVE: To evaluate the persistence of effects on health and development at age 5 years of the Infant Health and Development Program, an early childhood intervention that was provided to low-birth-weight (LBW) premature infants from neonatal discharge through age 3 years. DESIGN: Randomized, controlled, multicenter trial, stratified by two LBW groups: lighter (< or = 2000 g) and heavier (2001 to 2500 g). SETTING: Eight socioeconomically heterogeneous clinical sites. PARTICIPANTS: Of 985 eligible infants weighing 2500 g or less and at 37 weeks' or less gestational age, 377 infants were randomly assigned to the intervention group and 608 to the follow-up only group. About two thirds of the infants in each group were in the lighter LBW stratum, and one third were in the heavier LBW stratum. INTERVENTION: The intervention group received home visits (from neonatal discharge through age 3 years) as well as center-based schooling (from 1 to 3 years of age). Children in both groups received pediatric surveillance. MAIN OUTCOME MEASURES: Cognitive development, behavioral competence, and health status. RESULTS: At age 5 years, the intervention group had full-scale IQ scores similar to children in the follow-up only group. However, in the heavier LBW stratum, children in the intervention group had higher full-scale IQ scores (3.7 points higher; P = .03) and higher verbal IQ scores (4.2 points higher; P = .02). No significant differences between intervention and follow-up only groups in cognitive measures at age 5 years were noted in the lighter LBW infants. The intervention and follow-up groups were similar in behavior and health measures regardless of LBW stratum. CONCLUSION: The early childhood intervention provided in the first 3 years of life had effects on heavier LBW premature infants' IQ and verbal performance at age 5 years that were not observed for lighter LBW premature infants. The intervention did not affect health or behavior at age 5 years in either LBW stratum.

Loss of infectivity by progeny virus from alpha interferon-treated human immunodeficiency virus type 1-infected T cells is associated with defective assembly of envelope gp120.

Levels of human immunodeficiency virus (HIV) DNA, RNA, or p24 antigen and reverse transcriptase activity in T-cell cultures treated with 500 IU of recombinant alpha interferon (rIFN alpha) per ml were comparable to those in control cultures. Radioimmunoprecipitation analysis of proteins in lysates of IFN-treated T cells documented a marked accumulation of HIV proteins. Localization of gp120 by immunofluorescence showed a diffuse pattern in IFN-treated cells quite distinct from the ring pattern in untreated control cells. That large quantities of gp120 in aberrant cell compartments might affect HIV morphogenesis was confirmed in infectivity studies: virions from IFN-treated cells were 100- to 1,000-fold less infectious than an equal number of virions from control cells. Direct examination of IFN-treated and control HIV-infected cells by transmission electron microscopy showed little difference in the number or distribution of viral particles. However, quantitation of gp120 by immunogold particle analysis revealed a marked depletion of envelope glycoprotein in virions released from IFN-treated cells. This defect in gp120 assembly onto mature viral particles provides a molecular basis for this loss of infectivity.

Growth status and growth rates of a varied sample of low birth weight, preterm infants: a longitudinal cohort from birth to three years of age.

To obtain follow-up growth data on a large sample of low birth weight, preterm infants, 985 infants were monitored longitudinally in an eight-site collaborative program until 3 years of age, corrected for prematurity. The growth of 608 of these infants was described previously through 1 year of age. In the full sample, 149 infants weighed less than or equal to 1250 gm at birth, 474 between 1250 and 2000 gm, and 362 between 2000 and 2500 gm. Thirty-three percent were white, 53% were black, and 11% were Hispanic. Weight, length, and head circumference were measured at birth and at 40 weeks and 4, 8, 12, 18, 24, 30, and 36 months gestation-corrected age in at least 862 infants each time. Descriptive statistics and estimated growth rates for all growth variables and a body mass index (height in kilograms per square meter), plotted by sex and birth weight group, demonstrated growth patterns lower than published standards for term infants of the same age and sex. These patterns of growth differed by birth weight group. Little catch-up was noted by the 36-month examination for gestation-corrected age for any birth weight group. We conclude that low birth weight, preterm infants have different patterns of growth than term infants during the first 3 years of life, even with plotting corrected for gestational age.

Costs incurred by parents of very low birth weight infants after the initial neonatal hospitalization.

To assess the economic impact of the posthospitalization care of very low birth weight (VLBW) infants, the costs incurred in the first year of life by 32 VLBW infants were compared with those incurred by 34 term, comparison infants. Diaries and quarterly interviews revealed that VLBW infants averaged $10,139 in direct medical charges compared with $1179 for the term infants; the differential in charges was greatest in the first two quarters and virtually disappeared by the fourth quarter. In addition, expenditures associated with transportation and child care presented an added substantial burden, although only the former were significantly higher for the VLBW infants. Clinicians may need to inquire specifically about the burden on family resources because, despite the economic burden and evidence of less social support, the parents of VLBW infants were less likely to perceive their child's care as having an impact on the family than were the parents of term children.

Growth patterns of low birth weight preterm infants: a longitudinal analysis of a large, varied sample.

To obtain growth data on a large sample of low birth weight preterm infants, we monitored 608 infants longitudinally in an eight-site collaborative program. Ninety-nine infants weighed less than or equal to 1250 gm at birth, 289 between 1250 and 2000 gm, and 220 infants between 2000 and 2500 gm. Thirty-four percent were white, 52% black, and 14% Hispanic. Weight, height, and head circumference were measured at birth and at 40 weeks and 4, 8, and 12 months of gestation-corrected age on at least 553 infants each time. Descriptive statistics for all growth variables and a body mass index (kilograms per square meter), plotted by sex and birth weight group, demonstrated growth patterns lower than published standards for term infants of the same age and sex. These patterns of growth differed by birth weight group. No catch-up growth was noted by the 12-month examination (gestation-corrected age) for any birth weight group. We conclude that low birth weight preterm infants have different patterns of growth than term infants during the first year of life, even with plotting corrected for gestational age.

A new method for delivering a taste without fluids to preterm and term infants.

A new method for administering a taste to preterm and term infants has been developed that does not necessitate the delivery of rapid solutions. Sucrose, a sugar that in solution was shown to potentiate sucking behavior, was embedded in gelatin-based nipples that continuously release sweet taste when mouthed or sucked. The gelatin nipples and comparable latex nipples were adapted to measure sucking behavior and were tested in a within-subject design. The gelatin nipples potentiated sucking in preterm and term infants by increasing the frequency and strength of the responses. Few sucking measures varied significantly for preterm and term infants. Those that did vary might be attributable to differences in physical stamina, rather than to orosensory or hedonic factors. It was concluded that the flavored gelatin nipple provides an effective method for studying taste in infants and offers the possibility of routine chemosensory stimulation for research and clinical applications.

Growth and metabolic response of premature infants fed whey- or casein-dominant formulas after hospital discharge.

We conducted a double-blind, randomized study to test the hypothesis that a whey-dominant formula permits a growth and metabolic advantage over a casein-dominant formula in preterm infants after hospital discharge. Nineteen low birth weight infants were studied for 6 months from the time of discharge. Ten received a casein-dominant formula, and nine received a whey-dominant formula. Growth (weight, length, head circumference, mid-arm circumference, and skin-fold thickness), biochemical measurements (alkaline phosphatase activity, acid-base status, and hemoglobin, serum total protein, albumin, and urea nitrogen levels), and quantity of formula intake did not differ significantly between the groups over a 6-month study period. Serum transthyretin and urea nitrogen concentrations differed significantly between the two feeding groups at the day of entry into the study only. The results indicate that, after hospital discharge, premature infants fed a whey-dominant formula do not differ in growth or biochemical measurements from those fed a casein-dominant formula.

Half-dose immunization for diphtheria, tetanus, pertussis: response of preterm infants.

The American Academy of Pediatrics currently recommends administering full-dose diphtheria, tetanus, pertussis, (DTP) vaccine to preterm infants, beginning at 2 months' chronologic age. Many physicians, however, continue to administer DTP vaccine at a reduced dosage in an attempt to lessen side effects. This study was designed to quantitate the immune response of 20 preterm infants immunized with half-dose DTP vaccine and to determine the nature and extent of side effects. Control subjects were 25 preterm infants immunized with full-dose vaccine. Although 96% of infants who received a full dose were able to mount a serologic response to pertussis after a second dose of DTP, 45% of infants who received a half dose were unable to mount a similar immune response to pertussis even after a third dose of DTP and required a full-dose (fourth dose of DTP) vaccine to better ensure protection. Serologic responses to diphtheria and tetanus were similar in the two groups. The incidence of side effects in preterm infants receiving both full-dose and half-dose DTP was less than that seen in a full-term population. Thus, the physician caring for the preterm infant should adhere to the American Academy of Pediatrics' recommendation for the immunization of preterm infants and offer full-dose DTP vaccine at the routine time intervals of 2, 4, 6, and 15 or 18 months' chronologic age to ensure adequate protection.