黃仁昊,楊利,楊玉,柯江維,謝理玲,張東光,彭曉紅,曹蘭芳
性激素結合球蛋白在低齡女童乳房早發育中的臨床價值
黃仁昊1,2,楊利1,楊玉1,柯江維3,謝理玲1,張東光1,彭曉紅1,曹蘭芳1,2
1.江西省兒童醫院內分泌遺傳代謝科 江西省兒童遺傳代謝性疾病臨床醫學研究中心,江西南昌 330006;2.南昌大學兒科醫學院,江西南昌 330006;3.江西省兒童醫院檢驗科,江西南昌 330006
探討性激素結合球蛋白(sex hormone-binding globulin,SHBG)在低齡女童乳房早發育(premature thelarche,PT)中的臨床價值。選取2020年6月至2021年12月于江西省兒童醫院就診的1~3歲PT女童308例,根據乳房Tanner分期將其分為A1組(Tanner分期為Ⅱ期,226例)和A2組(Tanner分期大于Ⅱ期,82例),另選取同期于本院行健康體檢的1~3歲女童45例納入A3組。所有受試女童采用化學免疫發光法檢測SHBG,分析其在低齡女童中不同乳房發育階段的差異。A2組女童的SHBG水平顯著低于A1組[(160.12±28.55)nmol/L(167.44±23.12)nmol/L,=–2.30,<0.05]和A3組[(160.12±28.55)nmol/L(169.84±15.26)nmol/L,=–2.12,<0.05],但A1組和A3組女童的SHBG水平比較差異無統計學意義(=–0.67,=0.50)。SHBG與兒童乳房發育進程有關,可作為輔助判斷性發育進程的指標。當低齡女童SHBG降低,應密切隨訪監測性發育情況,警惕中樞性性早熟的發生。
性激素結合球蛋白;女童;乳房早發育;年齡
性早熟是指女孩在8歲、男孩在9歲以前呈現內外生殖器和第二性征發育,與正常青春期發育順序相似,根據下丘腦–垂體–性腺軸是否提前啟動可分為中樞性性早熟、部分性性早熟和外周性性早熟[1]。乳房早發育(premature thelarche,PT)是部分性性早熟的常見類型,除乳房發育外,無其他第二性征發育。PT被認為是一種自限性過程,但有研究表明PT可發展為中樞性性早熟,其風險因年齡而異[2]。近年來,隨著飲食及生活方式的改變,中樞性性早熟的發病率逐年升高,其可導致兒童的成年身高受損,并可引起兒童出現社會心理問題,嚴重影響少年兒童的健康成長[3],因此早期識別尤為重要。性激素結合球蛋白(sex hormone-binding globulin,SHBG)是一種血漿糖蛋白,可結合雄激素和雌激素,并調節它們對靶組織的生物利用度[4]。在性早熟發育過程中雄激素和雌激素平衡的改變可影響SHBG水平。本文通過對不同乳房發育分期PT低齡女童的SHBG水平研究,為臨床PT女童的早期診治提供新的依據。
選取2020年6月至2021年12月于江西省兒童醫院就診的1~3歲PT女童308例。納入標準:①足月產,無缺氧窒息搶救史,出生身長、體質量正常;②內分泌專科體檢乳房Tanner分期[5]為Ⅱ期及以上,不伴其他性發育體征;③女童。排除標準:①合并慢性心、肺、消化道及其他系統疾病者;②有染色體病、基因突變或遺傳代謝性疾病者;③有醫源性或外源性甾體類激素用藥史者;④有卵巢囊腫或其他內分泌腫瘤影響性激素分泌者。根據乳房Tanner分期將其分為A1組(Tanner分期為Ⅱ期,226例)和A2組(Tanner分期大于Ⅱ期,82例)。另選取同期于本院行健康體檢的1~3歲女童45例納入A3組,其身高和體質量均在同年齡段正常均值±2個標準差以內且無第二性征出現。本研究經江西省兒童醫院倫理委員會審核批準(倫理審批號:JXSETYY-YXKY-20200015),所有受試女童家長均自愿參與并簽署知情同意書。
入組女童均檢查身高、體質量、乳房發育情況;同時抽取靜脈血,采用SIMENS IMMULITE 2000化學發光免疫分析儀檢測SHBG,試劑盒購自英國西門子醫學診斷產品有限公司。A1組、A2組女童進行雌二醇(estradiol,E2)、黃體生成素(luteinizing hormone,LH)和卵泡刺激素(follicle-stimulating hormone,FSH)檢測。

A1組和A2組女童的E2、LH和FSH比較差異均無統計學意義(>0.05),見表1。
A2組女童的SHBG水平顯著低于A1組[(160.12±28.55)nmol/L. (167.44±23.12)nmol/L,=–2.30,<0.05]和A3組[(160.12±28.55)nmol/L(169.84±15.26)nmol/L,=–2.12,<0.05],但A1組和A3組女童的SHBG水平比較差異無統計學意義(=–0.67,=0.50)。
隨著社會的發展,性早熟發病率逐年升高,發病年齡有所提前[6]。過早出現青春發育跡象極大增加父母的擔憂。雖然低齡女童中中樞性性早熟少見,但部分初診PT的病例也可發展為中樞性性早熟[7]。根據中樞性性早熟診斷指南,促性腺激素釋放激素(gonadotropin-releasing hormone,GnRH)激發實驗作為診斷中樞性性早熟的金標準,LH峰值≥5.0U/L提示性腺軸啟動[8]。Vestergaard等[9]通過研究3歲以下沒有性早熟跡象的健康女童對GnRH激發實驗的生理反應發現,10個月至3歲的女孩對GnRH測試的反應與年齡相關,其GnRH激發實驗的LH峰值為(5.20±3.96)U/L。意大利一項包含450例患兒的回顧性研究表明,在小于3歲的特發性PT女童中,對GnRH激發實驗出現高促性腺激素反應不能診斷中樞性性早熟,且發現基礎激素水平及GnRH激發后性激素水平無法幫助預測進展,甚至在部分出現乳房消退或進展為中樞性性早熟的女童中觀察到LH峰值水平的重疊[10]。目前對低齡女童的GnRH激發實驗缺乏既定的參考值,本研究顯示低齡女童不同乳房分期的基礎性激素水平未見差異。

表1 A1組和A2組女童的性激素水平比較[M(Q1,Q3)]
SHBG是一種由肝臟合成并分泌的血漿糖蛋白,作為關鍵性類固醇(如睪酮和E2)的轉運糖蛋白發揮作用,在這些類固醇向其靶組織的運輸、生物利用和代謝清除中起關鍵作用[11]。目前SHBG多應用于多囊卵巢綜合征、肥胖、糖尿病等的研究[12]。E2是類固醇激素,可與SHBG結合并轉運,在性分化中發揮重要作用,如乳房發育、月經來潮、骨骺板閉合等[13]。SHBG在不同年齡段的體內濃度是不同的,一般來說在新生兒中水平較低,然后穩步增加,在幼兒期達到高峰,隨著青春期的臨近又逐漸下降,青春期時達到成人水平[14]。目前關于低齡女童SHBG水平的研究較少。丹麥一項研究選取191名性發育女童對其各項體格檢查指標和激素水平進行比較,其中性早熟組SHBG水平較PT組顯著降低,推斷SHBG水平有助于鑒別PT女孩和性早熟女孩[15]。馮緒芬等[16]通過對特發性中樞性性早熟和單純性PT女童間SHBG水平的研究發現,特發性中樞性性早熟女童的SHBG水平明顯低于單純性PT女童和青春期前女童。本研究結果顯示,A2組女童血SHBG水平低于A1組和A3組,認為SHBG水平與性發育進程呈負相關,SHBG降低時,血液中游離E2增多,組織利用增加,性腺發育提前或出現性腺發育進程增快,因此當出現SHBG降低,應密切觀察隨訪。但只有在乳房Tanner分期進展超過Ⅱ期時這種差異才有統計學意義,這可能與SHBG易受其他內分泌因素如肥胖、糖尿病和甲狀腺疾病等的影響有關。
綜上所述,對因PT就診的低齡女童,特別是3歲以下者,若出現SHBG下降,應密切隨訪性發育情況,做到早發現、早診斷、早干預。
[1] CHEUICHE A V, DA SILVEIRA L G, DE PAULA L C P, et al. Diagnosis and management of precocious sexual maturation: An updated review[J]. Eur J Pediatr, 2021, 180(10): 3073–3087.
[2] 王燕, 王愛萍, 孔莉芳, 等. 嬰幼兒乳房發育的全國多中心研究初探[J]. 中華兒科雜志, 2014, 52(1): 5–10.
[3] 林園園, 徐婷婷. 不同劑量重組人生長激素治療女性中樞性性早熟患兒的效果及對雌激素水平和發育指標的影響[J]. 中國婦幼保健, 2021, 36(18): 4261–4264.
[4] LI Y, FANG L, YAN Y, et al. Association between human SHBG gene polymorphisms and risk of PCOS: A Meta-analysis[J]. Reprod Biomed Online, 2021, 42(1): 227–236.
[5] 江載芳, 申昆玲, 沈穎. 諸福棠實用兒科學[M]. 8版. 北京:人民衛生出版社,2015.
[6] SENNING D L, RIX M, ANDERSEN G, et al. Idiopathic precocious puberty is common in girls[J]. Ugeskr Laeger, 2019, 181(29): V02190130.
[7] SEYMEN KARABULUT G, ATAR M, ?IZMECIO?LU JONES F M, et al. Girls with premature thelarche younger than 3 years of age may have stimulated luteinizing hormone greater than 10 IU/L[J]. J Clin Res Pediatr Endocrinol, 2020, 12(4): 377–382.
[8] 中華醫學會兒科學分會內分泌遺傳代謝學組, 《中華兒科雜志》編輯委員會. 中樞性性早熟診斷與治療共識(2015)[J]. 中華兒科雜志, 2015, 53(6): 412–418.
[9] VESTERGAARD E T, SCHJ?RRING M E, KAMPERIS K, et al. The follicle-stimulating hormone (FSH) and luteinizing hormone (LH) response to a gonadotropin- releasing hormone analogue test in healthy prepubertal girls aged 10 months to 6 years[J]. Eur J Endocrinol, 2017, 176(6): 747–753.
[10] BIZZARRI C, SPADONI GL, BOTTARO G, et al. The response to gonadotropin releasing hormone (GnRH) stimulation test does not predict the progression to true precocious puberty in girls with onset of premature thelarche in the first three years of life[J]. J Clin Endocrinol Metab, 2014, 99(2): 433–439.
[11] ANDRIESSEN V C, LIGHTBOURNE M, FLIPPO C, et al. Homozygous SHBG variant (rs6258) linked to gonadotropin- independent precocious puberty in a young girl[J]. J Endocr Soc, 2021, 5(10): bvab125.
[12] MADSEN T E, LUO X, HUANG M, et al. Circulating SHBG (sex hormone-binding globulin) and risk of ischemic stroke: Findings from the WHI[J]. Stroke, 2020, 51(4): 1257–1264.
[13] QU X, DONNELLY R. Sex hormone-binding globulin (SHBG) as an early biomarker and therapeutic target in polycystic ovary syndrome[J]. Int J Mol Sci, 2020, 21(21): 8191.
[14] ELMLINGER M W, KüHNEL W, RANKE M B. Reference ranges for serum concentrations of lutropin (LH), follitropin (FSH), estradiol (E2), prolactin, progesterone, sex hormone-binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEAS), cortisol and ferritin in neonates, children and young adults[J]. Clin Chem Lab Med, 2002, 40(11): 1151–1160.
[15] S?MOD M E, VESTERGAARD E T, KRISTENSEN K, et al. Increasing incidence of premature thelarche in the central region of Denmark - Challenges in differentiating girls less than 7 years of age with premature thelarche from girls with precocious puberty in real-life practice[J]. Int J Pediatr Endocrinol, 2016, 2016: 4.
[16] 馮緒芬, 吳鐵牛, 宋孝光. 性激素結合球蛋白與性激素在鑒別性早熟和單純乳房發育中的應用[J]. 江西醫藥, 2019, 54(10): 1247–1249, 1275.
Clinical value of sex hormone-binding globulin in young girls with premature thelarche
HUANG Renhao, YANG Li, YANG Yu, KE Jiangwei, XIE Liling, ZHANG Dongguang, PENG Xiaohong, CAO Lanfang
1.Department of Endocrinology, Genetics and Metabolism, Jiangxi Provincial Children’s Hosptial, Jiangxi Provincial Clinical Research Center for Children’s Genetic Metabolic Diseases, Nanchang 330006, Jiangxi, China; 2.College of Pediatrics, Nanchang University, Nanchang 330006, Jiangxi, China; 3.Department of Clinical Laboratory, Jiangxi Provincial Children’s Hosptial, Nanchang 330006, Jiangxi, China
To investigate the clinical value of sex hormone-binding globulin (SHBG) in premature thelarche (PT) young girls .A total of 308 PT girls aged 1 to 3 years old who were treated in Jiangxi Provincial Children’s Hosptial from June 2020 to December 2021 were selected and divided into A1 group (226 cases with Tanner stage Ⅱ) and A2 group (82 cases with Tanner stage greater than Ⅱ) according to breast Tanner stage. Another 45 girls aged 1 to 3 who underwent physical examination in our hospital during the same period were included in A3 group. The difference of SHBG in different stages of breast development in young girls was analyzed by chemiluminescence assay.The SHBG level of girls in A2 group was significantly lower than that in A1 group [(160.12±28.55) nmol/L(167.44±23.12) nmol/L,=–2.30,<0.05] and A3 groups [(160.12±28.55) nmol/L(169.84±15.26) nmol/L,=–2.12,<0.05]. However, there was no significant difference in SHBG level between group A1 and group A3 (=–0.67,=0.50).SHBG is related to breast development in children, and can be used as an indicator to judge sexual development. In young girls with decreased SHBG, sexual development should be closely monitored and the occurrence of central precocious puberty should be vigilant.
Sex hormone-binding globulin; Girl; Premature thelarche; Age
R725
A
10.3969/j.issn.1673-9701.2023.28.003
江西省衛生健康委科技計劃(20201104)
楊利,電子信箱:yangli1169@163.com
(2022–12–12)
(2023–09–13)