Endocrine manifestations of chromosome 22q11.2 microdeletion syndrome.
BACKGROUND
Endocrine abnormalities, including hypocalcemia, thyroid dysfunction, and short stature, are associated with chromosome 22q11.2 microdeletion syndrome. This study was undertaken to examine the frequencies and clinical features of endocrine abnormalities in patients with 22q11.2 microdeletion syndrome.


METHODS
We analyzed 61 patients with 22q11.2 microdeletion syndrome diagnosed based on the verification of microdeletion by fluorescent in situ hybridization (FISH) using a probe of the DiGeorge syndrome critical region (TUPLE1) at 22q11.2 and a control probe, ARSA at 22q13. Serum total calcium, phosphorus, and intact parathyroid hormone (PTH) levels were measured, thyroid function test was performed, and serum IGF-1 and IGFBP-3 levels were also estimated. Height and weight of patients were compared with individual chronological ages.


RESULTS
Hypocalcemia was found in 20 patients (32.8%), and overt hypoparathyroidism in 8 (13.1%). Two patients (3.3%) showed autoimmune thyroid diseases, 1 each with Graves' disease and Hashimoto thyroiditis. Ten patients (16.4%) were below the third percentile in height, but the serum IGF-1 level was normal in 9 out of these 10 patients.


CONCLUSIONS
Our findings show that patients with chromosome 22q11.2 microdeletion syndrome present with variable endocrine manifestations and variable clinical phenotypes. In addition to FISH analysis, careful endocrine evaluations are required in patients with this microdeletion syndrome, particularly for those with hypoparathyroidism or thyroid dysfunction.
Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Jin-Ho
JH
Choi
Young-Lim
YL
Shin
Gu-Hwan
GH
Kim
Eul-Ju
EJ
Seo
Youngho
Y
Kim
In-Sook
IS
Park
Han-Wook
HW
Yoo
D001827:Body Height / Q000235:genetics / Q000502:physiology; D002118:Calcium / Q000097:blood; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics*; D004700:Endocrine System Diseases / Q000097:blood / Q000235:genetics*; D005260:Female; D006801:Humans; D006996:Hypocalcemia / Q000235:genetics; D007011:Hypoparathyroidism / Q000235:genetics; D007223:Infant; D007231:Infant, Newborn; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008137:Longitudinal Studies; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood; D010758:Phosphorus / Q000097:blood; D013959:Thyroid Diseases / Q000235:genetics
D018972:Insulin-Like Growth Factor Binding Protein 3; D010281:Parathyroid Hormone; D010758:Phosphorus; D007334:Insulin-Like Growth Factor I; D002118:Calcium