Hiéronimus Sylvie, Bec-Roche Magali, Pedeutour Florence, Lambert Jean Claude, Wagner-Malher Kathy, Mas Jean Christophe, Sadoul Jean Louis, Fénichel Patrick
Department of Endocrinology and Reproductive Medecine, Nice University Hospital, BP 3079, 06202 Nice cedex 3, France.
Eur J Endocrinol. 2006 Jul;155(1):47-52. doi: 10.1530/eje.1.02180.
Clinical features associated with microdeletion of chromosome 22q11 (del(22)(q11)) are highly variable. Increased awareness of this condition is needed among specialists such as endocrinologists to reduce diagnostic delay and improve clinical care. The purpose of this study was to describe the phenotype of patients with del(22)(q11), focusing on parathyroid gland dysfunction.
Charts of 19 patients, including one kindred of three, known to have del(22)(q11) diagnosed by fluorescence in situ hybridization (FISH) were reviewed from the register of the department of Medical Genetics. Major clinical features including hypoparathyroidism phenotype were collected.
Parathyroid dysfunction was present in 8 out of 16 patients (50%). Six patients were diagnosed with overt hypoparathyroidism. Hypocalcemia manifested as laryngeal stridor within the first days of life (n = 3), seizures in infancy (n = 1) and adolescence (n = 2). The connection between hypoparathyroidism and diagnosis of del(22)(q11) was belated at the median age of 18 years. One patient had presented with transient neonatal hypoparathyroidism, and one patient had latent hypoparathyroidism. Within the kindred family, the phenotype variability including that of parathyroid dysfunction was as marked as between unrelated individuals. Standard karyotype failed to detect the deletion in 15 out of 19 cases.
Abnormal parathyroid function in the del(22)(q11) ranges from severe neonatal hypocalcemia to latent hypoparathyroidism. Del(22)(q11) should be considered as a potential cause of hypocalcemia even in young adult. When suspected, the diagnosis requires investigation by FISH. Furthermore, long-term calcemia follow-up is needed in normocalcemic patients with del(22)(q11) because of the possible evolution to hypocalcemic hypoparathyroidism.
22q11染色体微缺失（del(22)(q11)）相关的临床特征高度可变。内分泌科医生等专科医生需要提高对这种疾病的认识，以减少诊断延迟并改善临床护理。本研究的目的是描述del(22)(q11)患者的表型，重点关注甲状旁腺功能障碍。
从医学遗传学部门的登记册中回顾了19例已知通过荧光原位杂交（FISH）诊断为del(22)(q11)的患者的病历，其中包括一个三口之家。收集了包括甲状旁腺功能减退表型在内的主要临床特征。
16例患者中有8例（50%）存在甲状旁腺功能障碍。6例患者被诊断为明显的甲状旁腺功能减退。低钙血症表现为出生后数天内的喉喘鸣（n = 3）、婴儿期（n = 1）和青春期（n = 2）的癫痫发作。甲状旁腺功能减退与del(22)(q11)诊断之间的关联在中位年龄18岁时才被发现。1例患者表现为短暂性新生儿甲状旁腺功能减退，1例患者为潜伏性甲状旁腺功能减退。在家族中，包括甲状旁腺功能障碍在内的表型变异与无关个体之间一样明显。19例病例中有15例标准核型未能检测到缺失。
del(22)(q11)患者的甲状旁腺功能异常范围从严重的新生儿低钙血症到潜伏性甲状旁腺功能减退。即使在年轻成年人中，del(22)(q11)也应被视为低钙血症的潜在原因。怀疑时，诊断需要通过FISH进行检查。此外，由于del(22)(q11)的正常血钙患者可能会发展为低钙性甲状旁腺功能减退，因此需要进行长期血钙随访。
