Kimura Takuro, Umino Satoko, Kitamura Miyuki, Yatsuga Shuichi
Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, JPN.
Department of Neonatology, St. Mary's Hospital, Kurume, JPN.
Cureus. 2021 Aug 22;13(8):e17362. doi: 10.7759/cureus.17362. eCollection 2021 Aug.
Immunoglobulin G4 (IgG4)-related disorders are characterized by tissue hypertrophy due to IgG4-positive cell infiltration and increased serum IgG4 levels. IgG4-related hypophysitis (IgG4-RH) is characterized by pituitary hypertrophy, IgG4-positive cell infiltration, central diabetes insipidus, and increased serum IgG4 levels. IgG4-RH is diagnosed through diagnostic criteria. A few cases of IgG4-RH in children have been reported. We report a case of CDI with increased serum IgG4 levels that failed to meet the diagnostic criteria of IgG4-RH. The patient developed polyuria and polydipsia at age 11 and was diagnosed as having idiopathic CDI at age 12. The patient was not treated with steroids and is well controlled with antidiuretic hormones. It has been reported that pediatric IgG4-RH differs from that of adults in several respects. We believe that the pediatric IgG4-RH may not fit the diagnostic criteria of adults. There may be also other cases of increased serum IgG4 levels in pediatric patients with idiopathic CDI. We do not know if they are subtypes of IgG4-RH or if serum IgG4 levels are by chance raised in CDI, however, we report them here because IgG4-RH in children may be different from that in adults.
免疫球蛋白G4（IgG4）相关疾病的特征是由于IgG4阳性细胞浸润导致组织肥大以及血清IgG4水平升高。IgG4相关垂体炎（IgG4-RH）的特征是垂体肥大、IgG4阳性细胞浸润、中枢性尿崩症以及血清IgG4水平升高。IgG4-RH通过诊断标准进行诊断。已有少数儿童IgG4-RH病例的报道。我们报告一例血清IgG4水平升高但不符合IgG4-RH诊断标准的中枢性尿崩症病例。该患者11岁时出现多尿和烦渴，12岁时被诊断为特发性中枢性尿崩症。患者未接受类固醇治疗，使用抗利尿激素控制良好。据报道，儿童IgG4-RH在几个方面与成人不同。我们认为儿童IgG4-RH可能不符合成人的诊断标准。特发性中枢性尿崩症的儿童患者中可能还存在其他血清IgG4水平升高的病例。然而，我们尚不清楚它们是否为IgG4-RH的亚型，或者血清IgG4水平在中枢性尿崩症中升高是否为偶然现象，不过我们在此报告这些病例是因为儿童IgG4-RH可能与成人不同。
