日本新生児成育医学会雑誌　36(2)：134-139；2024　

日本新生児成育医学会雑誌　第36巻　第2号　134 ～ 139頁（2024年）

受付日：2024．02．16

受理日：2024．04．19

生後早期に高アンモニア血症と低血糖を来した下垂体柄断裂症候群の1 例

A Neonatal Case of Pituitary Stalk Interruption Syndrome with Hyperammonemia and Hypoglycemia

順天堂大学　医学部　小児科学講座

Department of Pediatrics, Juntendo University, Faculty of Medicine

橋本わかば・山田啓迪・佐藤浩之・齋藤暢知・幾瀨　圭・池野　充・菅沼広樹・春名英典・久田　研・田久保憲行・清水俊明

Wakaba HASHIMOTO，Hiromichi YAMADA，Hiroyuki SATO，Nobutomo SAITO，Tamaki IKUSE，Mitsuru IKENO， Hiroki SUGANUMA，Hidenori HARUNA，Ken HISATA，Noriyuki TAKUBO，Toshiaki SHIMIZU

Key Words：pituitary stalk interruption syndrome，combined pituitary hormone deficiency，invisible stalk syndrome，hypoglycemia

下垂体柄断裂症候群（pituitary stalk interruption syndrome：PSIS）は，様々な重症度の下垂体機能低下症を呈 する稀な疾患である。我々は新生児期にPSIS と診断し，早期に治療介入を行った新生児例を経験した。症例は在 胎38 週4 日，体重2,826g で出生した男児で，生後15 時間に低血糖，活気不良を認め，前医管理入院となり，血液 検査では当初高アンモニア血症がみられ，集中管理目的に当院へ転院搬送となったが，高アンモニア血症は経過中 に正常化した。その後，活気不良・筋緊張低下に対する精査目的に日齢18 に行った頭部MRI 検査で異所性後葉と 下垂体柄の消失を認め，PSIS と複合型下垂体機能低下症（combined pituitary hormone deficiency：CPHD）と診 断し，内分泌学的評価からホルモン補充療法を開始した。PSIS では下垂体機能の内分泌学的評価と低下・欠乏した 機能に応じたホルモン補充療法が重要となるが，軽症例は新生児期に気づかれないまま成人期に診断に至る症例も ある。治療の遅れは認知機能や生命予後へ影響を与えうるため，早期の診断と治療介入が大切である。新生児期に 低血糖や遷延する活気低下を認めた場合は同疾患を考慮すべきである。

Pituitary stalk interruption syndrome（ PSIS） is a rare disease that presents with a variety of hypopituitarism symptoms. We report a case of neonatal PSIS diagnosed and treated in infancy. Because of fetal bradycardia, the male infant was born by vacuum extraction at 38 weeks and 4 days of gestation. His birth weight was 2,826 g and Apgar score was 8 at 1 min and 9 at 5 min after birth. He presented with severe hypoglycemia, transient hyperammonemia（318 μg/dL in venous blood, 259 μg/dL in arterial blood）, prolonged jaundice, and poor vitality since birth. A head MRI scan performed at day 18 showed ectopic posterior pituitary, loss of the anterior pituitary and pituitary stalk. We diagnosed him with PSIS and combined pituitary hormone deficiency （CPHD）, performed a thorough endocrinologic workup, and initiated hormone replacement therapy. In PSIS, hormone replacement therapy is important in response to decreased or deficient pituitary function. However, because the symptoms of PSIS are often nonspecific, mild cases may go unnoticed in the neonatal period and become diagnosed in adulthood. Hormone replacement therapy should be performed as soon as possible, because delayed or lack of appropriate treatment of CPHD can be life-threatening. PSIS should be considered in cases of unexplained hypoglycemia or decreased vitality in the neonatal period.