引起性早熟的原因
//hzlcwl.cn2009-09-15 16:47:58 來(lai)源(yuan):全民(min)健康(kang)網
概述
(precocious puberty)是指青春(chun)(chun)期提早(zao)(zao)(zao)出(chu)現即女性(xing)(xing)(xing)(xing)(xing)(xing)在(zai)8歲以(yi)(yi)前(qian)(qian)出(chu)現性(xing)(xing)(xing)(xing)(xing)(xing)腺增大和第二性(xing)(xing)(xing)(xing)(xing)(xing)征,或者(zhe)在(zai)10歲之前(qian)(qian)出(chu)現,男性(xing)(xing)(xing)(xing)(xing)(xing)在(zai)9歲以(yi)(yi)前(qian)(qian)發(fa)育按發(fa)病(bing)機制的不同,性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu)一般可分為兩(liang)大類:促性(xing)(xing)(xing)(xing)(xing)(xing)腺激素釋放(fang)激素(GnRH)依(yi)賴性(xing)(xing)(xing)(xing)(xing)(xing)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu)(真性(xing)(xing)(xing)(xing)(xing)(xing)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu))和非(fei)GnRH依(yi)賴性(xing)(xing)(xing)(xing)(xing)(xing)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu)(假(jia)性(xing)(xing)(xing)(xing)(xing)(xing)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu));前(qian)(qian)者(zhe)稱(cheng)中樞(shu)性(xing)(xing)(xing)(xing)(xing)(xing)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu)或完(wan)全性(xing)(xing)(xing)(xing)(xing)(xing)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu),后者(zhe)稱(cheng)外周性(xing)(xing)(xing)(xing)(xing)(xing)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu)此外,不完(wan)全性(xing)(xing)(xing)(xing)(xing)(xing)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)熟(shu),如單純(chun)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)發(fa)育單純(chun)性(xing)(xing)(xing)(xing)(xing)(xing)早(zao)(zao)(zao)現,有學(xue)者(zhe)歸(gui)入青春(chun)(chun)發(fa)育的變(bian)異類型(xing)。
性早(zao)熟的病因(yin)很多,可按下丘腦—垂體—性腺(xian)軸功能(neng)是否提前發動,分為中樞性(真(zhen)性)和外周性(假性)兩類(lei)。
(一)中樞性(xing)性(xing)早熟(CPP)
亦稱真性性早熟,由于下丘腦—垂體—性腺軸功能過早啟動,GnRH脈沖分泌,患兒除有第二性征的發育外,還有卵巢或的發育。性發育的過程和正常青春期發育的順序一致。只是年齡提前。主要包括繼發于中樞神經系統的器質性病變和特發性性早熟。
1、特發(fa)性性早熟
又(you)稱(cheng)體質性(xing)(xing)性(xing)(xing)早熟(shu),是由于下丘腦對性(xing)(xing)激(ji)素的負反(fan)饋的敏感性(xing)(xing)下降,使(shi)促性(xing)(xing)腺素釋放激(ji)素過早分泌所致,女性(xing)(xing)多見,約(yue)占女孩CPP的80%以上,而(er)**則僅為(wei)40%左右。
2、繼發性性早熟
多見于中樞神經系統異常,包括:①腫瘤或占位性病變:下丘腦錯構瘤、囊腫、肉芽腫,②中樞神經系統感染,③獲得性損傷:外傷、術后放療或化療,④發育異常:腦積水、視中(zhong)隔(ge)發育(yu)不全等。
3、其他疾病
原發性甲(jia)狀腺(xian)功能減(jian)低癥(zheng)。
(二)外周性性早熟
亦稱假性性早熟(shu)。是非受控于(yu)下丘腦—垂體、性腺(xian)功(gong)能所引起(qi)的(de)性早熟(shu),有(you)第(di)二(er)性征發育(yu)(yu),有(you)性激素(su)水平升(sheng)高,但下丘腦—垂體—性腺(xian)軸不(bu)成熟(shu)、無(wu)性腺(xian)的(de)發育(yu)(yu)。
1、性腺腫瘤
卵(luan)巢顆(ke)粒—泡膜細(xi)胞瘤(liu)、黃體(ti)瘤(liu)、睪丸(wan)間(jian)質(zhi)細(xi)胞瘤(liu)、畸(ji)胎瘤(liu)等。
2、腎上腺疾病
腎上腺腫瘤、先天性(xing)腎上腺皮質(zhi)增生等。
3、外源性
如(ru)含雌激素的藥物、食(shi)物、品(pin)等。
4、其他
McCune—Albright綜合征(zheng)。
(三(san))部分性(xing)性(xing)早熟
單(dan)(dan)純(chun)早(zao)發(fa)育、單(dan)(dan)純(chun)性(xing)早(zao)發(fa)育、單(dan)(dan)純(chun)性(xing)早(zao)初潮。
[[編輯推薦:性早熟的分類]]