Fracture risk among children and adolescents with celiac disease: a nationwide cohort study.

BACKGROUND: Metabolic bone disease is a common manifestation of celiac disease (CD). We aimed to assess fracture risk among children and adolescents with CD compared with a matched group. METHODS: This registry-based cohort study included 2372 children with CD who were matched 1:5 to 11,860 children without CD. Demographic and clinical data were obtained from the electronic database of Meuhedet, a health maintenance organization. Fracture events at ages 1-18 years were identified by coded diagnoses. RESULTS: The overall fracture incidence rate was 256 per 10,000 patient-years (PY) in the CD group and 165 per 10,000 PY in the comparison group (p < 0.001). The hazard ratio (HR) to have a fracture was 1.57 (95% CI 1.43-1.73, p < 0.001) for the CD group compared to the matched group. The HR for multiple fractures was 1.67 (95% CI 1.38-2.01, p < 0.001). Analysis of the pre- and post-diagnosis periods separately showed that the HR for fractures in the pre-diagnosis period was 1.64 (95% CI 1.42-1.88, p < 0.001) for the CD group compared to the matched group, and 1.52 (95% CI 1.26-1.71, p < 0.001) in the period from diagnosis to the end of the follow-up period. CONCLUSIONS: Children with CD had increased fracture risk both preceding and following the diagnosis of CD. IMPACT: One manifestation of celiac disease (CD) is metabolic bone disease, including osteoporosis and impaired bone mineralization. We found increased fracture risk among children with CD, both preceding the CD diagnosis and during the years following the diagnosis. Recognition of the high risk of fractures in this population may help promote prevention. Further studies are needed to evaluate changes in bone quantity and quality after initiation of a gluten-free diet, and to identify those at risk for persistent metabolic bone disease.

Linear growth of children with X-linked hypophosphatemia treated with burosumab: a real-life observational study.

To assess the long-term efficacy of burosumab for pediatric patients with X-linked hypophosphatemia, focusing on linear growth. This multi-center retrospective study included 35 pediatric patients who began treatment with burosumab between January 2018 and January 2021. We collected clinical data, anthropometric measurements, laboratory results, and Rickets Severity Score (RSS), from 2 years prior to treatment initiation and up to 4 years after. Burosumab was initiated at a mean age of 7.5 ± 4.4 years (range 0.6-15.9), with a mean initial dose of 0.8 ± 0.3 mg/kg, which was subsequently increased to 1.1 ± 0.4 mg/kg. The patients were followed for 2.9 ± 1.4 years (range 1-4) after initiating burosumab. Serum phosphorus levels increased from 2.7 ± 0.8 mg/dl at burosumab initiation to 3.4 ± 0.6 mg/dl after 3 months and remained stable (p < 0.001). Total reabsorption of phosphorus increased from 82.0 ± 6.8 to 90.1 ± 5.3% after 12 months of treatment (p = 0.041). The RSS improved from 1.7 ± 1.0 at burosumab initiation to 0.5 ± 0.6 and 0.3 ± 0.6 after 12 and 24 months, respectively (p < 0.001). Both height z-score and weight z-score improved from burosumab initiation to the end of the study: from - 2.07 ± 1.05 to - 1.72 ± 1.04 (p < 0.001) and from - 0.51 ± 1.12 to - 0.11 ± 1.29 (p < 0.001), respectively. Eight children received growth hormone combined with burosumab treatment. Height z-score improved among those who received growth hormone (from - 2.33 ± 1.12 to - 1.94 ± 1.24, p = 0.042) and among those who did not (from - 2.01 ± 1.01 to - 1.66 ± 1.01, p = 0.001). CONCLUSION:  Burosumab treatment in a real-life setting improved phosphate homeostasis and rickets severity and enhanced linear growth. WHAT IS KNOWN: • Compared to conventional therapy, burosumab treatment has been shown to increase serum phosphate levels and reduce the severity of rickets. • The effect of burosumab on growth is still being study. WHAT IS NEW: • Height z-score improved between the start of burosumab treatment and the end of the study (-2.07 ± 1.05 vs. -1.72 ± 1.04, p < 0.001). • Eight children received burosumab combined with growth hormone treatment without side effects during the concomitant treatments.

Transient neonatal hyperinsulinism: early predictors of duration.

OBJECTIVES: Hyperinsulinism is the most common cause of recurrent hypoglycemia in infants, with transient and permanent forms. Currently, there are no effective tools to predict severity and time to resolution in infants with transient hyperinsulinism (tHI). Therefore, our objective was to assess whether early glucose trends predict disease duration in tHI. METHODS: A retrospective, pilot cohort of infants admitted with tHI was phenotyped for clinical and laboratory parameters. Blood glucose (BG) values were collected from the first documented hypoglycemia for 120 h (five days). RESULTS: In 27 neonates with tHI, the presence of fetal distress (p=0.001) and higher mean daily BG (p=0.035) were associated with shorter time to resolution of hypoglycemia. In a further sensitivity analysis that grouped the cohort by the presence or absence of fetal distress, we found that in neonates without fetal distress, lower mean daily glucose was associated with longer disease duration (R2=0.53, p=0.01). CONCLUSIONS: Our pilot data suggests that predictors for disease duration of tHI may be elicited in the first week of life, and that tHI associated with fetal distress may represent a distinct clinical entity with a shorter time course.

Multicentric carpotarsal osteolysis syndrome (MCTO) with generalized high bone turnover and high serum RANKL: Response to denosumab.

MCTO is a rare disorder, caused by mutations in the MafB gene, a negative regulator of receptor activator of nuclear factor-кB ligand (RANKL). Manifestations include carpal and tarsal osteolysis and renal failure. Pathophysiology is poorly understood, and no effective treatment is available. In this case report we describe a patient with MCTO (MafB, mutation c.206C>T, p.Ser69Leu), diagnosed at the age of 5 years. At 7 years, skeletal survey showed diffuse osteopenia. BMD was mildly reduced, and bone turnover markers increased. He was treated with denosumab, a human monoclonal RANKL inhibitor for two years. Each injection was followed by a marked reduction in C-telopeptide (CTX). Following denosumab his BMD and bone symptoms improved and the osteolysis stabilized. At the age of 13 years, osteoporosis was diagnosed using high resolution peripheral quantitative computed tomography (HRpQCT) and serum RANKL was found to be markedly increased. This initial experience suggests that the associated osteoporosis may be ameliorated by denosumab, although further study will be needed to understand the appropriate dose, frequency, and the extent of efficacy. Monitoring of CTX and bone specific alkaline phosphatase will be especially useful in this regard. Further study in other MCTO patients is also needed to determine whether high bone turnover is specific to this mutation or more common than previously appreciated. We propose a model in which osteolysis in this condition is strongly associated with the systemic osteoporosis.