日本新生児成育医学会雑誌　37(1)：104-108；2025　

日本新生児成育医学会雑誌　第37巻　第1号　104 ～ 108頁（2025年）

受付日：2024．06．13

受理日：2024．08．01

異所性尿管開口により巨大骨盤部嚢胞を呈した胎児期発症の精嚢嚢胞

A Case of Seminal Vesicle Cyst with Ectopic Ureter Opening to Giant Pelvic Cyst

＊ 1 独立行政法人地域医療機能推進機構（JCHO）九州病院　小児科，＊ 2 九州大学病院　小児科

＊ 1 Department of Pediatrics, Japan Community Healthcare Organization Kyushu Hospital， ＊ 2 Department of Pediatrics, Kyushu University Hospital

詫間青葉＊ 1 ＊ 2・大村隼也＊ 1・横田千恵＊ 1・山本順子＊ 1

Aoba TAKUMA ＊ 1 ＊ 2，Junya OHMURA ＊ 1，Chie YOKOTA ＊ 1，Junko YAMAMOTO ＊ 1

Key Words：pelvic cyst，congenital anomalies of the kidney and urinary tract，multicystic dysplastic kidney

診断に苦慮した胎児期発症の精嚢嚢胞を経験したので報告する。症例は在胎37 週2 日，2,478g で出生した男児。 妊娠30 週時に左多嚢胞性異形成腎（multicystic dysplastic kidney：MCDK）と骨盤部嚢胞を指摘され，生後，膀 胱を背側から圧排する5cm 大の単房性嚢胞と左MCDK がみられた。逆行性尿路造影，下部消化管造影，腹部CT， MRI 検査では嚢胞の発生由来は不明であり，日齢10 に腹腔鏡下嚢胞ドレナージ術を行ったが再拡大した。5 か月 時の膀胱鏡検査で尿道との交通は確認できず，レノグラムや排泄性尿路造影でも嚢胞は造影されなかった。嚢胞は 9cm に増大し9 か月時に嚢胞亜全摘術を行った。左重複尿管があり嚢胞には尿管異所開口と両側精管の流入がみら れた。病理組織学的検査で精嚢嚢胞と診断した。術後嚢胞は縮小し無症状で経過している。 　小児では精嚢嚢胞は稀な疾患であるが同側腎形態異常の合併が知られており，腎形態異常を有する骨盤部嚢胞で は本疾患も念頭に置く必要がある。

We report a case of seminal vesicle cyst with ectopic ureter opening to giant pelvic cyst. The patient was a boy who was born at 37 weeks and 2 days of gestation, weighing 2,478 grams. He was observed to have a left multicystic dysplastic kidney（ MCDK） and a pelvic cyst at 30 weeks of gestation. Postnatal ultrasonography showed a left MCDK and a unilocular cyst of 5 cm diameter with a compressed bladder. Retrograde urethrography, lower gastrointestinal contrast imaging, computed tomography, and magnetic resonance imaging did not reveal the origin of the cyst. Laparoscopic cyst drainage was performed at day 10. There was no urethral traffic on the cystogram. Cystoscopy at 5 months showed no urethral traffic, and no cyst showed contrast on renogram or excretory urography. Since the cyst grew to 9 cm in diameter and frequent urination occurred due to compression of the bladder, cyst reduction was performed at 9 months. The left complete double ureter and ectopic ureter opening were observed to enter the cyst along with bilateral vas deferens. The bilateral vas deferens were preserved, and a subtotal cystectomy with resection of the left kidney and ureter was performed. Histopathological examination of the resected cyst revealed a seminal vesicle cyst. Postoperatively, the diameter of the cyst reduced to 1 cm and remained asymptomatic without further enlargement. Seminal vesicle cyst is a rare malformation, but tends to be associated with ipsilateral renal abnormalities. If a pelvic cyst with renal abnormalities is identified in a patient, it is important to consider this condition as a possible differential diagnosis.