Oxygen radicals and asbestos carcinogenesis.

Asbestos fibers have been shown to generate reactive oxygen species using a variety of in vitro assays. It is hypothesized that these highly reactive metabolites mediate the development of malignant mesothelioma induced by asbestos fibers. DNA is a potential target of oxidant attack. Adaptive responses to oxidant injury have been described during exposure of mesothelial cells to asbestos fibers in vitro. Failure of these adaptive responses may lead to genetic instability and alterations in oncogenes and tumor suppressor genes that confer a proliferative advantage to emerging neoplastic mesothelial cells.

Pediatric resident and faculty knowledge of the Denver II.

OBJECTIVE: To assess knowledge of the Denver II, the revised developmental screening tool recommended by the American Academy of Pediatrics, in residents and faculty, and to evaluate a teaching intervention for incoming postgraduate year 1 (PGY-1) trainees. DESIGN: A cross-sectional test of knowledge for all subjects and pretesting and posttesting of the incoming PGY- 1 trainees. SETTING: University of Texas-Houston Medical School Department of Pediatrics. PARTICIPANTS: Faculty (n = 9) and residents (n = 78), including an intervention group (n = 45), of incoming PGY-1 trainees over 2 years. INTERVENTIONS: Postgraduate year 1 trainees in both 1994 through 1995 and 1995 through 1996 viewed the Denver II training videotape on entry into a continuity clinic. Trainees were encouraged to perform Denver II evaluations on at least 1 appropriate patient at each pediatric clinic session and had access to Denver II support materials. MAIN OUTCOME MEASURES: Scores on the Denver II Proficiency Written Test, self-reported measures of comfort, and number of Denver II evaluations performed. RESULTS: The mean (SD) test scores for incoming, preintervention PGY-1 trainees (n = 45) (41.3 [9.6]) did not differ from scores for outgoing PGY-1 trainees (n = 13) (38.5 [10.4]) who had not received the intervention. Postintervention PGY-1 test results were significantly improved (59.4 [10.6]) (P<.001). Test scores for upper-level residents who had participated in the developmental pediatrics rotation (n = 14) were better (55.3 [9.31), but all scored below passing. Residents who had not yet participated in the developmental pediatrics rotation (n = 19) and members of the general pediatric faculty (n = 9) had scores similar to those of PGY-1 trainees (40.9 [13.4] and 39.0 [15.1], respectively). CONCLUSIONS: Residents had a greater knowledge of the Denver II after completing a developmental pediatrics rotation. Our intervention produced significant improvement in PGY-1 trainees' knowledge, raising it to levels similar to those of upper-level residents exposed to developmental pediatrics. Faculty were not expert in using the Denver II.

Accuracy of clinical judgment in neonatal jaundice.

CONTEXT: Recommendations for management of jaundice in newborns presume thatjaundice is a reliable clinical finding and that the pattern and intensity of jaundice reflects the degree of elevation of the serum bilirubin level. OBJECTIVES: To determine whether experienced observers agree in describing the extent of jaundice and to evaluate the reliability of visual assessment as an indication for the measurement of serum bilirubin levels. DESIGN: Comparison of independent judgments of the extent of jaundice between examiners and with actual serum bilirubin measurements. SETTING: Well-newborn nursery in an urban public hospital. PARTICIPANTS: A convenience sample of 122 healthy term newborns whose bilirubin concentration was measured in the course of standard newborn care. Observers were experienced pediatric nurse practitioners, pediatric house staff, and pediatric attending physicians. RESULTS: Agreement was moderately good for whether an infant's skin was darkly pigmented (K = 0.56). However, agreement between observers regarding the presence of jaundice at each specific body site was poor (0%-23% agreement beyond chance); correlation between estimated bilirubin concentrations was similarly poor (Pearson correlation coefficient, 0.37). Correlation between estimated and actual bilirubin values was slightly better (Pearson correlation coefficient, 0.43-0.54). CONCLUSIONS: Clinical examination with visual assessment for jaundice in newborns is neither reliable nor accurate. The decision to perform serum bilirubin testing should be based on additional factors.

Contribution of long-bone radiographs to the management of congenital syphilis in the newborn infant.

OBJECTIVE: To determine the contribution of long-bone radiographs to the diagnosis and management of newborn infants at risk for congenital syphilis. DESIGN: Historical cohort. SETTING: Three large hospitals in Houston, Tex. PATIENTS: Eight hundred fifty-three live born infants who were evaluated for the presence of congenital syphilis. INTERVENTION: Long-bone radiographs done as part of the diagnostic evaluation for the presence of congenital syphilis. MAIN OUTCOME MEASURE: Changes in diagnostic classification or management decisions that were based on radiographic findings in the long bones. RESULTS: For 450 infants, radiographic results did not affect management because clinical or historical factors were present that dictated treatment: 26 infants had clinical symptoms of congenital syphilis (65% [17] had abnormalities on radiographs); and 424 infants were born to mothers who were untreated or reinfected (5.9% [25] had abnormalities on radiographs). All of these infants required a full course of therapy regardless of radiologic findings. Born to mothers with possibly inadequate therapy (according to 1993 Centers for Disease Control and Prevention guidelines), 237 asymptomatic newborn infants were candidates for a single injection of penicillin G benzathine if the results of their evaluations were normal; of these, 2 (0.8%) had abnormal radiographic findings. Of the 166 infants born to adequately treated mothers with appropriately falling serologic titer levels, 1 (0.6%) had abnormal radiographic findings (P=.99 between groups). The results of the long-bone radiographs did not alter management for any of the 853 infants who were evaluated for congenital syphilis. CONCLUSIONS: Long-bone radiographic findings, often abnormal in symptomatic infants, do not differentiate between active infection and past infection. The use of long-bone radiographs should be reconsidered in the routine evaluation of infants for congenital syphilis.

Can sick children tell time?: emergency department presentation patterns of critically ill children.

OBJECTIVE: Children show a consistent pattern of ED use, with the majority of patients presenting during the late afternoon and evening hours. This study evaluated whether such a diurnal pattern also exists for critically ill children and the implications of such a presentation pattern on ED staffing. METHODS: A review was performed of the ED diagnoses and times of presentation for children less than 12 years of age at 28 nonpediatric hospitals over the six-year period from July 1990 to October 1996. In addition to total ED pediatric visits, a subset of critically ill children (CIC) were identified as those with an ED diagnosis of: meningitis, cardiac arrest, diabetic ketoacidosis, status epilepticus, meningococcemia, or epiglottitis, or those undergoing endotracheal intubation in the ED. A second group of non-critically ill children (NCIC) was composed of children with an ED diagnosis of otitis media, tonsillitis, or pharyngitis. Data collected on each patient included age, diagnosis, site of care, and time of service. Presentation patterns for all three groups were compared for time of day, with statistical analysis through chi-square, ANOVA, and Spearman's rho correlation. RESULTS: A total of 409,820 pediatric ED visits were examined, with 688 CIC children and 28,344 NCIC identified. Presentation patterns for NCIC visits mirrored those of the total pediatric population, with the traditional increase in the late afternoon and evening hours (correlation 0.96). CIC presented much more erratically, with a distribution spread more uniformly throughout the day compared with the total pediatric population (correlation 0.72). Thirty-seven percent of CIC presented during the evening hours of 16:00 to 24:00, compared with 49% for NCIC and 53% for the total pediatric population, while 22% of CIC presented from 24:00 to 08:00 compared with only 13% of NCIC and 10% of total pediatric patients (p < 0.001). CONCLUSION: Critically ill children present more uniformly throughout the day and do not have the same presentation patterns as ambulatory children. ED staffing should reflect this difference and not focus pediatric ED services simply on hours of peak pediatric visits.

Late versus early surgical correction for congenital diaphragmatic hernia in newborn infants.

BACKGROUND: Congenital diaphragmatic hernia, although rare (1 per 2-4,000 births), is associated with high mortality and cost. Opinion regarding the timing of surgical repair has gradually shifted from emergent repair to a policy of stabilization using a variety of ventilatory strategies prior to operation. Whether delayed surgery is beneficial remains controversial. OBJECTIVES: To summarize the available data regarding whether surgical repair in the first 24 hours after birth rather than later than 24 hours of age improves survival to hospital discharge in infants with congenital diaphragmatic hernia who are symptomatic at or immediately after birth. SEARCH STRATEGY: Search of MEDLINE (1966-2002), EMBASE (1978-2002) and the Cochrane databases using the terms "congenital diaphragmatic hernia" and "surg*"; citations search, and contact with experts in the field to locate other published and unpublished studies. SELECTION CRITERIA: Studies were eligible for inclusion if they were randomized or quasi-randomized trials that addressed infants with CDH who were symptomatic at or shortly after birth, comparing early (<24 hours) vs late (>24 hours) surgical intervention, and evaluated mortality as the primary outcome. DATA COLLECTION AND ANALYSIS: Data were collected regarding study methods and outcomes including mortality, need for ECMO and duration of ventilation, both from the study reports and from personal communication with investigators. Analysis was performed in accordance with the standards of the Cochrane Neonatal Review Group. MAIN RESULTS: Two trials met the pre-specified inclusion criteria for this review. Both were small trials (total n<90) and neither showed any significant difference between groups in mortality. Meta-analysis was not performed because of significant clinical heterogeneity between the trials. REVIEWER'S CONCLUSIONS: There is no clear evidence which favors delayed (when stabilized) as compared with immediate (within 24 hours of birth) timing of surgical repair of congenital diaphragmatic hernia, but a substantial advantage to either one cannot be ruled out. A large, multicenter randomized trial would be needed to answer this question.

Short versus standard duration oral antibiotic therapy for acute urinary tract infection in children.

BACKGROUND: The optimal duration of oral antibiotic therapy for urinary tract infection (UTI) in children has not been determined. A number of studies have compared single dose therapy to standard therapy for UTI, with mixed results. A course of antibiotics longer than a single dose but shorter than the usual 7-10 days might decrease the relapse rate and still provide some of the benefits of a shortened course of antibiotics. OBJECTIVES: The objective of this review was to assess the benefits and harms of short-course (2-4 days) compared to standard duration (7-14 days) oral antibiotic treatment for acute UTI in children. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register (Cochrane Library Issue 3, 2002) MEDLINE (1966 - September 2002) and EMBASE (1988 -September 2002) without language restriction. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials comparing short-term (2-4 days) with standard (7-14 days) oral antibiotic therapy were selected if they studied children aged three months to 18 years with culture proven UTI. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. Statistical analyses were performed using the random effects model and the results expressed as relative risk (RR) with 95% confidence intervals (95% CI). MAIN RESULTS: Ten trials were identified in which 652 children with lower tract UTI were evaluated. There was no significant difference in the frequency of positive urine cultures between the short (2-4 days) and standard duration oral antibiotic therapy (7-14 days) for UTI in children at 0-10 days after treatment (eight studies: RR 1.06; 95% CI 0.64 to 1.76) and at one to 15 months after treatment (10 studies: RR 0.95; 95% CI 0.70 to 1.29). There was no significant difference between short and standard duration therapy in the development of resistant organisms in UTI at the end of treatment (one study: RR 0.57, 95% CI 0.32 to 1.01) or in recurrent UTI (three studies: RR 0.39, 95% CI 0.12 to 1.29). REVIEWER'S CONCLUSIONS: A 2-4 day course of oral antibiotics appears to be as effective as 7-14 days in eradicating lower tract UTI in children.

Late versus early surgical correction for congenital diaphragmatic hernia in newborn infants.

BACKGROUND: Congenital diaphragmatic hernia, although rare (1 per 2-4,000 births), is associated with high mortality and cost. Opinion regarding the timing of surgical repair has gradually shifted from emergent repair to a policy of stabilization using a variety of ventilatory strategies prior to operation. Whether delayed surgery is beneficial remains controversial. OBJECTIVES: To summarize the available data regarding whether surgical repair in the first 24 hours after birth rather than later than 24 hours of age improves survival to hospital discharge in infants with congenital diaphragmatic hernia who are symptomatic at or immediately after birth. SEARCH STRATEGY: Search of Medline (1966-1999), Embase (1978-1999) and the Cochrane databases using the terms "congenital diaphragmatic hernia" and "surg*"; citations search, and contact with experts in the field to locate other published and unpublished studies. SELECTION CRITERIA: Studies were eligible for inclusion if they were randomized or quasi-randomized trials that addressed infants with CDH who were symptomatic at or shortly after birth, comparing early (<24 hours) vs late (>24 hours) surgical intervention, and evaluated mortality as the primary outcome. DATA COLLECTION AND ANALYSIS: Data were collected regarding study methods and outcomes including mortality, need for ECMO and duration of ventilation, both from the study reports and from personal communication with investigators. Analysis was performed in accordance with the standards of the Cochrane Neonatal Review Group. MAIN RESULTS: Two trials met the pre-specified inclusion criteria for this review. Both were small trials (total n<90) and neither showed any significant difference between groups in mortality. Meta-analysis was not performed because of significant clinical heterogeneity between the trials. REVIEWER'S CONCLUSIONS: There is no clear support for either immediate (within 24 hours of birth) or delayed (until stabilized) repair of congenital diaphragmatic hernia, but a substantial advantage to either one cannot be ruled out. A large, multicenter randomized trial would be needed to answer this question.

Evidence syntheses in child health.

Evidence syntheses, also known as systematic reviews, differ from traditional reviews in that they are scientific evaluations of existing studies. Systematic reviews have explicit and reproducible methods and, as with any other scientific endeavor, the result of an evidence synthesis or systematic review can be critically appraised. Many sources for high-quality evidence syntheses now exist, with considerable support from government agencies to develop both the methods and the products of such reviews. Evidence syntheses can increase the efficiency and effectiveness of medical practice but face many hurdles, particularly in child health. These center around 4 areas: lack of high-quality primary studies, the difficulty of finding studies that do exist, the variability and usefulness of the outcome measures in child health, and problems with production and dissemination. Increasing attention to the need for high-quality child health research will help to ameliorate some of these issues, whereas solutions to others are under development or remain elusive.

Early-onset neonatal group B streptococcal infection: implications for practice.

Group B streptococcus (GBS) is the leading bacterial infection associated with morbidity and mortality of newborns in the United States. Most neonatal infections can be prevented through the use of intrapartum antimicrobial prophylaxis in women who are at increased risk for transmitting infection to their newborns. However, prevention strategies have not been implemented widely or consistently, and the incidence of neonatal GBS disease has not declined. An understanding of GBS epidemiology, clinical presentation, and prevention strategies enhances the PNP's decision-making skills in the nursery and strengthens the PNP's ability to evaluate and compare new approaches to GBS prevention.

Hepatitis B screening in pregnancy: practical aspects.

Hepatitis B may be acquired at birth from a mother who is a chronic carrier and may result in debilitating liver disease later in life. Screening of pregnant women and preventive measures have been shown to be clinically effective and at least marginally cost-effective. The Centers for Disease Control recommends universal screening of pregnant women. Cost-effectiveness has been evaluated using estimated costs and assuming patient compliance. The practical aspects of screening a high-risk population are described in the context of a single program, with discussion of excess costs and problems with implementation.

Evaluation of a lead screening program in Houston, Tex.

Universal screening for childhood lead poisoning is widely debated. Our purpose was to compare screening results at three pediatric clinics within Houston and to evaluate the effectiveness of screening according to published criteria. The clinics were chosen for their geographic and socioeconomic diversity. Children between 6 months and 6 years of age were tested, and the results were classified according to current guidelines. We screened 864 children. Results between sites were significantly different, P = 0.002. No children with blood lead levels greater than 0.45 mumol/L (9 micrograms/dL) were identified at Clinic C compared to 76 (8.8%) from Clinics A and B, but no site had children with levels greater than or equal to 2.20 mumol/L (45 micrograms/dL). The prevalence of childhood lead poisoning can vary even within the city. If regional screening is to replace universal screening, statewide as well as citywide data are needed to identify high-risk areas. This could be done by clinic site, zip code, or census track data with a minimum of 3000 children.

Evidence-based paediatrics.

Evidence-based medicine is practised widely in some specialties and is now part of many undergraduate and graduate medical curricula. However, the extent to which it is used in clinical paediatric practice is not known and its expansion remains a major challenge. Access to technology which facilitates literature searching, and development of journals addressing specific paediatric problems, will encourage the use of evidence-based medicine by the busy paediatrician. Informed practice of evidence-based medicine will ensure that clinical expertise is complemented by a thorough search, evaluation and judicious application of relevant information from the medical literature.

Total and differential leukocyte counts in clinically well children. Information or misinformation?

To determine whether the total and differential leukocyte count is of value as a case-finding test, we applied the evaluation criteria developed by the US Preventive Services Task Force. The criteria comprise review of the current burden of suffering of the disease to be prevented, the attributes of the intervention to be used, and the quality of the evidence available. A literature search revealed no evidence in the form of data from patients, so a chart review of all complete blood cell counts ordered during a 1-year period by one group of pediatricians was undertaken. At least one value outside of published normal ranges was found on 74.7% of the tests performed on clinically well children. No unsuspected illness was discovered as a result of an abnormal total and differential leukocyte count.

Is the practice of paediatric inpatient medicine evidence-based?

OBJECTIVE: To determine whether management provided to paediatric inpatients in general units was supported by high-level evidence. METHODS: A retrospective review was carried out of all patients (n = 142) admitted during one calendar month to two general paediatric units in the USA and Australia. For each patient, the primary diagnosis and primary treatment were determined. A literature review was performed to determine whether the therapy used was evidence-based. The main outcome measure was the level of evidence supporting the primary intervention for the primary diagnosis of each patient. RESULTS: Level I evidence (at least one randomized trial) supported the primary intervention used in 31% of paediatric admissions and level II evidence (convincing non-experimental evidence) supported the primary intervention in 44% of admissions. Primary interventions were not supported by evidence (level III) in only two patients. The remaining 24% of patients were admitted for observation or evaluation only, and received no primary medical or surgical intervention. Most patients whose interventions were supported by randomized trials were admitted with either asthma or appendicitis. CONCLUSIONS: Most primary interventions (75%) in paediatric inpatients were supported by high-level published evidence (level I or II). A large number of patients were admitted for evaluation or observation only, and received no therapeutic intervention. Evidence to support this action is not available.

Short compared with standard duration of antibiotic treatment for urinary tract infection: a systematic review of randomised controlled trials.

AIMS: To compare the effectiveness of short course (2-4 days) with standard duration oral antibiotic treatment (7-14 days) for urinary tract infection (UTI). METHODS: Meta-analysis of randomised controlled trials using a random effects model. Ten trials were eligible, involving 652 children with lower tract UTI recruited from outpatient or emergency departments. Main outcome measures were UTI at the end of treatment, UTI during follow up (recurrent UTI), and urinary pathogens resistant to the treating antibiotic. RESULTS: There was no significant difference in the frequency of positive urine cultures between the short (2-4 days) and standard duration therapy (7-14 days) for UTI in children at 0-7 days after treatment (eight studies: RR 1.06; 95% CI 0.64 to 1.76) and at 10 days to 15 months after treatment (10 studies: RR 1.01; 95% CI 0.77 to 1.33). There was no significant difference between short and standard duration therapy in the development of resistant organisms in UTI at the end of treatment (one study: RR 0.57, 95% CI 0.32 to 1.01) or in recurrent UTI (three studies: RR 0.39, 95% CI 0.12 to 1.29). CONCLUSION: A 2-4 day course of oral antibiotics is as effective as 7-14 days in eradicating lower tract UTI in children.