日本新生児成育医学会雑誌　第33巻　第1号　85 ～ 91頁（2021年）

日本新生児成育医学会雑誌　33(1)：85-91；2021　

受付日：2020．06．19

受理日：2020．10．06

超低出生体重児の中枢性尿崩症に対し，デスモプレシン口腔内崩壊錠を使用した1 例

A Case Report of Extremely Low Birth Weight Infant Diagnosed with Central Diabetes Insipidus by Oral Desmopressin

石井記念愛染園附属愛染橋病院　小児科

Department of Pediatrics, Aizenbashi Hospital

髙久保圭二・前川　周・尾上泰祐・織辺圭太・鈴木晶子・高尾大士・井石倫弘・甲斐明彦・隅　清彰・塩見正司

Keiji TAKAKUBO，Shu MAEKAWA，Taisuke ONOE，Keita ORIBE，Akiko SUZUKI，Daishi TAKAO，Tomohiro ISEKI，Akihiko KAI，Kiyoaki SUMI，Masashi SHIOMI

Key Words：extremely low birth weight infants，central diabetes insipidus，vasopressin load test，desmopressin orally disintegrating tablet，hypernatremia　

　症例は在胎期間24 週5 日，出生体重734g で出生した超低出生体重児の女児。日齢2 に両側の上衣下出血をきたした。日齢28 より持続する高Na 血症を認めたが，水分量の調整のみで血清Na 値は150mEq/L 前後で経過した。日齢50 に血液検査を行い血清浸透圧314mOsm/kgH2O，尿浸透圧92mOsm/kgH2O，バソプレシン0.9pg/mL と中枢性尿崩症を疑う所見であった。家族に説明し同意を得た上で，日齢89 にデスモプレシン口腔内崩壊錠を2.4μg/ kg 投与し，尿量減少と尿浸透圧上昇を認め中枢性尿崩症と確定診断した。その後，口腔内崩壊錠の投与下で有害事象なく生後5 か月で退院となった。一般的に小児ではバソプレシン負荷試験はデスモプレシン鼻腔内投与か皮下注射されることが多い。しかし早産児の報告は少なく効果が予測し難いため，その後の治療も考えデスモプレシン口腔内崩壊錠による負荷試験も考慮される。

Central diabetes insipidus（ CDI） is very rare among infants. We report an extremely low birth weight infant diagnosed with CDI. The female was born at 24 weeks and 5 days gestation and her birth weight was 734g. She had bilateral subependymal hemorrhages on day 2, but they did not worsen. Patent ductus arteriosus（ PDA） was surgically ligated with a clip on day 15. Water intake was increased from 140 to 190mL/kg/day, because her plasma sodium value was elevated to 154mEq/mL on day 28. However, her hypernatremia persisted and she developed polyuria with urine output of 4 ～ 5mL/kg/hr. CDI was suspected because her serum osmolality was 314mOsm/kgH2O, whereas urine osmolality was 92mOsm/kgH2O and vasopressin concentration was 0.9pg/mL on day 50. A challenge test was conducted with 2.4μg/kg of desmopressin obtained by dissolving orally disintegrating（ OD） tablets in water on day 89, and her urine volume decreased and urine osmolality increased, without any side effects. Therefore, we made a definitive diagnosis of CDI. We started her treatment with 1μg/dose of desmopressin solution, twice daily （0.68μg/kg/day）, and adjusted the dose based on her urine volume and serum sodium value as clinical markers. The drug dose was gradually increased to 3.3μ g/kg/day, and her hypernatremia improved and her general condition stabilized. She was discharged from the hospital at five months after birth. Hypernatremia and polyuria are very important findings when suspecting CDI. We experienced a case of extremely low birth weight infant with CDI, and succeeded in diagnosing and treating her with desmopressin solution without any side effects.