Bone density assessment in a cohort of pediatric patients affected by 22q11DS.
OBJECTIVE
Hypoparathyroidism and hypocalcemia are two of the most frequent clinical characteristics of 22q11-deletion syndrome (22q11DS). The aim of this study was to evaluate bone metabolism and density in a cohort of patients affected by 22q11DS.


METHODS
In 8 pediatric patients (mean age 11.5 years; range 7-16.4) affected by 22q11DS, creatinine, albumin, total and ionized calcium, phosphate, 25(OH) vitamin D, parathyroid hormone, osteocalcin, C-terminal telopeptide and interleukin 6 were assessed. Furthermore, bone mineral density (BMD) was determined by dual-energy X-ray absorptiometry procedure. 14 healthy children were considered as controls.


RESULTS
Most of the studied subjects were overweight and lacked quality physical activity. 40 % of the subjects had reduced calcium levels in the absence of related clinical symptoms and all patients also had inadequate levels of Vitamin D. The values of L1-L4 BMD were within the reference range in all patients (z score <2). However, after comparing the age-matched indexes of bone mineralization of patients with those of controls, the former had lower bone mineralization indexes than the latter.


CONCLUSIONS
In pediatric patients with 22q11DS, an initial and slight bone loss is evident. The incidence of hypocalcemia is underestimated because hypocalcemia is asymptomatic. Several factors contribute to bone impairment in children who still have to achieve bone mass peak. Therefore, we suggest strict monitoring of bone metabolism as well as BMD measurement in patients affected by 22q11DS.
Paediatric Department, Salesi Children Hospital, Umberto I Hospital, Polytechnic University of Marche, Ancona, Italy.
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Ficcadenti
Paediatric Department, Salesi Children Hospital, Umberto I Hospital, Polytechnic University of Marche, Ancona, Italy.
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Zallocco
Paediatric Department, Salesi Children Hospital, Umberto I Hospital, Polytechnic University of Marche, Ancona, Italy.
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Neri
Andrology Unit, Division of Endocrinology, Department of Clinical and Molecular Sciences, Umberto I Hospital, Polytechnic University of Marche, Via Conca 71, 60126, Ancona, Italy.
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Giovannini
Andrology Unit, Division of Endocrinology, Department of Clinical and Molecular Sciences, Umberto I Hospital, Polytechnic University of Marche, Via Conca 71, 60126, Ancona, Italy.
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Tirabassi
Andrology Unit, Division of Endocrinology, Department of Clinical and Molecular Sciences, Umberto I Hospital, Polytechnic University of Marche, Via Conca 71, 60126, Ancona, Italy. g.balercia@univpm.it.
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Balercia
D058165:22q11 Deletion Syndrome / Q000097:blood / Q000000981:diagnostic imaging / Q000503:physiopathology*; D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000502:physiology*; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D002118:Calcium / Q000097:blood; D002648:Child; D005260:Female; D006801:Humans; D006996:Hypocalcemia / Q000097:blood / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007011:Hypoparathyroidism / Q000097:blood / Q000000981:diagnostic imaging / Q000503:physiopathology*; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D015675:Osteocalcin / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood; D011859:Radiography; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood
D015415:Biomarkers; D015850:Interleukin-6; D010281:Parathyroid Hormone; D015675:Osteocalcin; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D002118:Calcium
22q11DS; Bone; Dual-energy X-ray absorptiometry; Pediatrics