Celia Rodd

Effect of Different Dosages of Oral Vitamin D Supplementation on Vitamin D Status in Healthy, Breastfed Infants: A Randomized Trial

IMPORTANCE Vitamin D supplementation in infancy is required to support healthy bone mineral accretion. A supplement of 400 IU of vitamin D per day is thought to support plasma 25-hydroxyvitamin D (25[OH]D) concentrations between 40 and 50 nmol/L; some advocate 75 to 150 nmol/L for bone health. OBJECTIVE To investigate the efficacy of different dosages of vitamin D in supporting 25(OH)D concentrations in infants. DESIGN, SETTING, AND PARTICIPANTS Double-blind randomized clinical trial conducted among 132 one-month-old healthy, term, breastfed infants from Montréal, Québec, Canada, between March 2007 and August 2010. Infants were followed up for 11 months ending August 2011 (74% completed study). INTERVENTION Participants were randomly assigned to receive oral cholecalciferol (vitamin D3) supplements of 400 IU/d (n=39), 800 IU/d (n=39), 1200 IU/d (n=38), or 1600 IU/d (n=16). MAIN OUTCOMES AND MEASURES The primary outcome was a plasma 25(OH)D concentration of 75 nmol/L or greater in 97.5% of infants at 3 months. Secondary outcomes included 25(OH)D concentrations of 75 nmol/L or greater in 97.5% of infants at 6, 9, and 12 months; 25(OH)D concentrations of 50 nmol/L or greater across all times; growth; and whole body and regional bone mineral content. Data were analyzed by intention to treat using available data, logistic regression, and mixed-model analysis of variance. RESULTS By 3 months, 55% (95% CI, 38%-72%) of infants in the 400-IU/d group achieved a 25(OH)D concentration of 75 nmol/L or greater vs 81%(95% CI, 65%-91%) in the 800-IU/d group, 92% (95% CI, 77%-98%) in the 1200-IU/d group, and 100% in the 1600-IU/d group. This concentration was not sustained in 97.5% of infants at 12 months in any of the groups. The 1600-IU/d dosage was discontinued prematurely because of elevated plasma 25(OH)D concentrations. All dosages established 25(OH)D concentrations of 50 nmol/L or greater in 97% (95% CI, 94%-100%) of infants at 3 months and sustained this in 98% (95% CI, 94%-100%) to 12 months. Growth and bone mineral content did not differ by dosage. CONCLUSIONS AND RELEVANCE Among healthy, term, breastfed infants, only a vitamin D supplement dosage of 1600 IU/d (but not dosages of 400, 800, or 1200 IU/d) increased plasma 25(OH)D concentration to 75 nmol/L or greater in 97.5% of infants at 3 months. However, this dosage increased 25(OH)D concentrations to levels that have been associated with hypercalcemia. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00381914.

Growth during maintenance hemodialysis: impact of enhanced nutrition and clearance.

Growth of children during maintenance hemodialysis has been reported to be uniformly poor, with a mean annual loss of 0.4 to 0.8 SD in height. We adopted an intensive program of closely monitored energy and protein intake with dialysis urea clearances exceeding conventional recommendations. Twelve prepubertal or early pubertal children (aged 7 months to 14 years) were monitored for an average of 2.2 years (range 4 to 81 months) while receiving maintenance hemodialysis. These children received an average of 90.6% and 155.9% of their recommended energy and protein nutritional intake, respectively. With a prescribed urea clearance of 5 mL/kg/min, we achieved a mean single treatment urea clearance normalized for total body water of 2.00, a urea reduction ratio of 84.7%, and an average time of hemodialysis of 14.8 h/wk, all well beyond current guidelines. Over the course of dialysis treatment, the improvement in height SD score was+0.31 SD/y (+0.32 excluding the 2 children treated with recombinant human growth hormone). Normal growth was achieved without overt obesity and was associated with normal pubertal growth spurt. These findings suggest that the combination of increased dialysis and adequate nutrition can promote normal growth in children treated with long-term hemodialysis.

Incident vertebral fractures among children with rheumatic disorders 12 months after glucocorticoid initiation: a national observational study.

To determine the frequency of incident vertebral fractures (IVF) 12 months after glucocorticoid (GC) initiation in children with rheumatic diseases and to identify children at higher risk.

High Incidence of Vertebral Fractures in Children With Acute Lymphoblastic Leukemia 12 Months After the Initiation of Therapy

PURPOSE Vertebral fractures due to osteoporosis are a potential complication of childhood acute lymphoblastic leukemia (ALL). To date, the incidence of vertebral fractures during ALL treatment has not been reported. PATIENT AND METHODS We prospectively evaluated 155 children with ALL during the first 12 months of leukemia therapy. Lateral thoracolumbar spine radiographs were obtained at baseline and 12 months. Vertebral bodies were assessed for incident vertebral fractures using the Genant semiquantitative method, and relevant clinical indices such as spine bone mineral density (BMD), back pain, and the presence of vertebral fractures at baseline were analyzed for association with incident vertebral fractures. RESULTS Of the 155 children, 25 (16%; 95% CI, 11% to 23%) had a total of 61 incident vertebral fractures, of which 32 (52%) were moderate or severe. Thirteen (52%) of the 25 children with incident vertebral fractures also had fractures at baseline. Vertebral fractures at baseline increased the odds of an incident fracture at 12 months by an odds ratio of 7.3 (95% CI, 2.3 to 23.1; P = .001). In addition, for every one standard deviation reduction in spine BMD Z-score at baseline, there was 1.8-fold increased odds of incident vertebral fracture at 12 months (95% CI, 1.2 to 2.7; P = .006). CONCLUSION Children with ALL have a high incidence of vertebral fractures after 12 months of chemotherapy, and the presence of vertebral fractures and reductions in spine BMD Z-scores at baseline are highly associated clinical features.

Hypercalcemia of the newborn: etiology, evaluation, and management

Abstract Hypercalcemia in infants is uncommon but has potentially serious sequelae. This review examines four cases of neonatal hypercalcemia, emphasizing appropriate investigations and treatment of acute and chronic hypercalcemia. The paper provides additional information as to the mechanisms of calcium dysregulation in idiopathic infantile hypercalcemia, Williams syndrome, vitamin D intoxication, and parathyroid and parathyroid-related protein disturbances.

Prevalence of Vertebral Fractures in Children with Chronic Rheumatic Diseases at Risk for Osteopenia

OBJECTIVES To determine the prevalence of and the risk factors for vertebral fractures in a cohort of children with chronic rheumatic diseases considered at risk for osteopenia. STUDY DESIGN We conducted a cross-sectional study of patients with chronic rheumatic diseases at the Montreal Childrens Hospital. RESULTS Of the 90 study participants (22 boys, 68 girls), 10 boys and 7 girls (19%) were found to have vertebral fractures. These 17 children had a total of 50 fractures, an average of 2.9 per affected child. Fractures in the upper thoracic region (T5-8) accounted for 55%. Only 56% of all fractures were symptomatic. With multivariate regression, we identified male sex (P < .01), body mass index z-score (P < .02), and cumulative glucocorticoid dose (P < .01) as significant predictors of the number of vertebral fractures. CONCLUSIONS Our study examined the prevalence of vertebral fractures in a high-risk pediatric population. Nineteen percent of our cohort had vertebral fractures. Significant risk factors for the development of vertebral fractures include male sex and cumulative glucocorticoid dose. Better understanding of the extent of the problem in this population will allow us to further refine screening guidelines and treatment in these patients.

The use of pamidronate in three children with renal disease

Abstract. The successful use of pamidronate, a bisphosphonate, for the treatment of hypercalcemia and/or osteopenia is reported in three children with renal failure or following renal transplant. Patient 1 was an 11-year-old post renal transplant male who received a single dose of IV pamidronate (0.5 mg/kg) for the treatment of acute hypercalcemia associated with a pathological fracture and subsequent immobilization. Prompt resolution of the hypercalcemia was seen. He received a second course of pamidronate (0.5 mg/kg per day for 3 days) for the treatment of osteopenia and has had a subsequent 15% increase in lumbar spine bone mineral content (BMC). Patient 2, a 14-year-old male on peritoneal dialysis, presented with symptomatic hypercalcemia associated with tertiary hyperparathyroidism. A single dose of IV pamidronate (0.4 mg/kg) was given with prompt resolution and prolonged control of his hypercalcemia. The third patient was a 16-year-old female, also in renal failure on peritoneal dialysis. Her course had been complicated by marked osteopenia. IV pamidronate (0.5 mg/kg per dose) was given on 3 successive days before and after renal transplant in an attempt to stabilize her bone mineral density (BMD) around the time of renal transplantation, when additional glucocorticoid was necessary. Her total body BMC and BMD remained stable pre and post transplant. The treatment was effective and well tolerated in all three patients. Hence pamidronate is safe and effective for the management of hypercalcemia and osteopenia in children with renal failure and/or renal transplant.

Incident vertebral fractures and risk factors in the first three years following glucocorticoid initiation among pediatric patients with rheumatic disorders

Vertebral fractures are an important yet underrecognized manifestation of osteoporosis in children with chronic, glucocorticoid‐treated illnesses. Our goal was to determine the incidence and clinical predictors of vertebral fractures in the 3 years following glucocorticoid initiation among pediatric patients with rheumatic disorders. Incident vertebral fractures were evaluated according to the Genant semiquantitative method on lateral radiographs at baseline and then annually in the 3 years following glucocorticoid initiation. Extended Cox models were used to assess the association between vertebral fractures and clinical risk predictors. A total of 134 children with rheumatic disorders were enrolled in the study (mean ± standard deviation (SD) age 9.9 ± 4.4 years; 65% girls). The unadjusted vertebral fracture incidence rate was 4.4 per 100 person‐years, with a 3‐year incidence proportion of 12.4%. The highest annual incidence occurred in the first year (6.0%; 95% confidence interval (CI) 2.9% to 11.7%). Almost one‐half of the patients with fractures were asymptomatic. Every 0.5 mg/kg increase in average daily glucocorticoid (prednisone equivalents) dose was associated with a twofold increased fracture risk (hazard ratio (HR) 2.0; 95% CI 1.1 to 3.5). Other predictors of increased vertebral fracture risk included: (1) increases in disease severity scores between baseline and 12 months; (2) increases in body mass index Z‐scores in the first 6 months of each 12‐month period preceding the annual fracture assessment; and (3) decreases in lumbar spine bone mineral density Z‐scores in the first 6 months of glucocorticoid therapy. As such, we observed that a clinically significant number of children with rheumatic disorders developed incident vertebral fractures in the 3 years following glucocorticoid initiation. Almost one‐half of the children were asymptomatic and thereby would have been undiagnosed in the absence of radiographic monitoring. In addition, discrete clinical predictors of incident vertebral fractures were evident early in the course of glucocorticoid therapy.

Thyroid Abnormalities as a Feature of DiGeorge Syndrome: A Patient Report and Review of the Literature

DiGeorge syndrome or anomaly consists of a developmental field defect which is characterized by congenital absence or hypoplasia of the thymus and parathyroids, as well as facial dysmorphism and congenital heart defects. Other congenital malformations may coexist, in particular, thyroid abnormalities. A case of congenital hypothyroidism and DiGeorge syndrome is reviewed. Necropsy, clinical, and experimental studies also show that thyroid abnormalities may be a feature of DiGeorge syndrome. Although this could be purely coincidental, our case suggests that thyroid gland dysgenesis may be more common than previously thought. Thus, children with the DiGeorge syndrome may be at higher risk for hypothyroidism. Because of this potential association, patients who are considered to have this anomaly should have early newborn thyroid screening.

Incident Vertebral Fractures in Children With Leukemia During the Four Years Following Diagnosis

OBJECTIVES The purpose of this article was to determine the incidence and predictors of vertebral fractures (VF) during the 4 years after diagnosis in pediatric acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS Children were enrolled within 30 days of chemotherapy initiation, with incident VF assessed annually on lateral spine radiographs according to the Genant method. Extended Cox models were used to assess the association between incident VF and clinical predictors. RESULTS A total of 186 children with ALL completed the baseline evaluation (median age, 5.3 years; interquartile range, 3.4-9.7 years; 58% boys). The VF incidence rate was 8.7 per 100 person-years, with a 4-year cumulative incidence of 26.4%. The highest annual incidence occurred at 12 months (16.1%; 95% confidence interval [CI], 11.2-22.7), falling to 2.9% at 4 years (95% CI, 1.1-7.3). Half of the children with incident VF had a moderate or severe VF, and 39% of those with incident VF were asymptomatic. Every 10 mg/m(2) increase in average daily glucocorticoid dose (prednisone equivalents) was associated with a 5.9-fold increased VF risk (95% CI, 3.0-11.8; P < .01). Other predictors of increased VF risk included VF at diagnosis, younger age, and lower spine bone mineral density Z-scores at baseline and each annual assessment. CONCLUSIONS One quarter of children with ALL developed incident VF in the 4 years after diagnosis; most of the VF burden was in the first year. Over one third of children with incident VF were asymptomatic. Discrete clinical predictors of a VF were evident early in the patients clinical course, including a VF at diagnosis.