Direct Estimation of the Total Number of Nephrons in Living Pediatric Patients Using Nephrectomy Specimens

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K08355
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 52050:Embryonic medicine and pediatrics-related
• Research Institution: Jikei University School of Medicine
• Principal Investigator: Hirano Daishi 東京慈恵会医科大学, 医学部, 講師 (90424663)
• Co-Investigator(Kenkyū-buntansha): 神崎 剛 東京慈恵会医科大学, 医学部, 助教 (00816473) ; 湯坐 有希 地方独立行政法人東京都立病院機構東京都立小児総合医療センター(臨床研究部), その他, 部長 (30277090) ; 西崎 直人 順天堂大学, 医学部, 先任准教授 (30561435)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: ネフロン数

Outline of Final Research Achievements

We examined pediatric patients with unilateral renal tumors undergoing nephrectomy. Stereological assessments of the areas of the cross-sections and cortex were performed to determine the volume and density of nonsclerotic glomeruli. Glomerular density was measured on high-resolution digital images of scanned specimens stained with PAS and HE, and measurement of the cortical and glomerular areas. The number and area of the glomeruli were measured. Kidneys from 21 children were examined. The estimated number of nephrons was significantly higher than reported for adult patients. The median number of glomeruli measured per patient was 64 (IQR, 60-78), and the median total number of nephrons per kidney was 950846 (IQR, 868760-1049293). This is one of the first studies to estimate the number of nephrons in the kidneys of living children. We contend that our results will provide a foundation for accurately determining the intrinsic renal reserve capacity.

Free Research Field

小児腎臓

Academic Significance and Societal Importance of the Research Achievements

加齢に伴うネフロンの消失の影響を除外できる小児例を対象とした総ネフロン数の計測の意義は非常に大きいと考えられる。今後はさらに症例数を増やし、ネフロン数決定因子の探索、腎機能障害や将来的な腎予後評価について検討したい。