Sonographic cortical bone thickness measurement: can it predict bone mineral density in the pediatric population?

PURPOSE: To explore sonographic cortical bone thickness (CoT) as a potential indicator of bone mineral density (BMD) measured by dual-energy X-ray absorptiometry for screening and diagnosing pediatric osteoporosis. METHODS: A prospective study included 41 osteopenic or osteoporotic patients and 52 healthy children. Radius cortical thickness (R-CoT), tibial cortical thickness (T-CoT), and second metatarsal cortical thickness (M-CoT) were measured by B-mode ultrasound; CoT values were compared between groups and the correlation between BMD and CoT was examined. RESULTS: There were no significant differences in R-CoT (P = 0.433), T-CoT (P = 0.057), and M-CoT (P = 0.978) values between the patient and control groups. No significant correlations were found between BMD T-scores and R-CoT (r = -0.073, P = 0.490), T-CoT (r = -0.154, P = 0.141), and M-CoT (r = 0.047, P = 0.657) values. CONCLUSION: Sonographic CoT values in children do not correlate with BMD values. Unlike in adults, sonographic CoT measurements do not appear to have a role in assessing BMD in the pediatric population.

Transcutaneous Bilirubin Levels and Risk of Significant Hyperbilirubinemia in Early-Term and Term Newborns.

OBJECTIVE: To compare the course of the transcutaneous bilirubin (TcB) values of early-term newborns with those of term newborns in the first month of life and to investigate whether early-term newborns have an increased risk of significant hyperbilirubinemia requiring treatment. DESIGN: A prospective, controlled cohort analysis. SETTING: A tertiary level mother-child birth and health care center. PARTICIPANTS: Four hundred early-term (37 0/7 to 38 6/7 weeks) and 320 term (39 0/7 to 41 6/7 weeks) newborns born during a 27-month period. METHODS: A total of six TcB measurements in a longitudinal manner were made in early-term and term newborns: the first two at 6 and 48 hours after birth and the next four on routine examination days (Days 4, 7, 15, and 30). Demographic characteristics, values of daily TcB measurements, number of newborns with significant hyperbilirubinemia, and risk of jaundice requiring treatment were compared between the two groups. RESULTS: All six TcB values were significantly greater in the early-term group than in the term group (p < .001 for each). Early-term newborns had a statistically significant increased risk of jaundice requiring treatment compared to term newborns (risk ratio = 1.91; 95% confidence interval [1.23-2.96]; p = .0046). Results of the repeated-measures analysis of variance and post hoc adjusted multiple comparison analysis showed that TcB levels increased to and peaked at 96 hours after birth and then gradually decreased to baseline (first measurement) levels at 30 days after birth in each group. CONCLUSIONS: Early-term newborns should not be treated as full-term newborns because they have significantly higher TcB levels. These newborns should be closely monitored for pathologic jaundice because they have increased risk for significant hyperbilirubinemia requiring phototherapy.

Investigation of the relationship between cord clamping time and risk of hyperbilirubinemia.

BACKGROUND: Although the relationship between umbilical cord clamping time and various parameters such as hemoglobin (Hb) levels, iron deficiency, and risk of neonatal jaundice has previously been studied, to the best of our knowleadge there have been no studies investigating the relationship between cord clamping time and the risk of significant hyperbilirubinemia. We aimed to investigate the relationship between the time of umbilical cord clamping and transcutaneous bilirubin (TcB) measurements made on various postnatal hours, Hb and serum total bilirubin (STB) levels measured on postnatal 4th day, and the risk of development of significant hyperbilirubinemia requiring phototherapy treatment. METHODS: Eligible newborns were divided into two groups on the basis of the time of cord clamping: those clamped late (60 seconds or more; Group I) and those clamped early (less than 60 seconds; Group II). Groups were compared with respect to the parameters of cord Hb, postnatal TcB measurements at 6th, 48th, 96th and 168th hours, and 96th hour Hb, STB and direct bilirubin levels. RESULTS: TcB levels at the 96th and 168th hour were significantly higher in Group I when compared to Group II (p < 0.001 and p < 0.001, respectively). The 96th hour STB level was significantly higher in Group I when compared to Group II (p < 0.001). The need of phototherapy requirement was higher in Group I when compared to Group II (p=0.001). Increase in cord blood Hb for each 1 gr/dl caused a 3.94-fold increased risk in the requirement of phototherapy treatment. Cord clamping time showed statistically significant positive correlations with both cord blood and 96th hour venous Hb levels, with both 96th hour and 168th hour TcB levels, and with 96th hour STB levels. CONCLUSIONS: Newborns whose cords are clamped late should be followed up closely with respect to high postnatal bilirubin levels and other risks associated with significant hyperbilirubinemia requiring phototherapy treatment.