Application Of Sex Hormone Binding Globulin And Sex Hormone In Distinguishing Girls' Idiopathic Central Precocious Puberty And Premature Thelarche

Background and aim:Precocious puberty?PP?is one of the most common endocrine diseases in adolescence,which refers to the appearance of menarche in girls before the age of 10or secondary sexual signs such as breast development,the growth of pubic hair and axillary hair before the age of 8.PP can be divided into true precocious puberty?most of the clinical true precocious puberty is idiopathic central precocious puberty,ICPP?,pseudo precocious puberty and partial precocious puberty?most of the clinical partial precocious puberty is simple breast early development,prematurity of larche,PT?.Early diagnosis and prevention is of great significance for the treatment of precocious puberty.At present,precocious puberty is diagnosed mainly by X-ray bone age measurement,breast and uterus ultrasound examination and GnRH excitation experiment,but due to the poor repeatability of radiation and ultrasound detection,and radiation detection should not be repeated in a short time.In addition,the GnRH excitation test needs repeated blood sampling in a short period of time,and children often have resistance mood,and this method can only identify whether children have developed into true precocious puberty,is short of early warning mechanism,and may miss the best expectation.Therefore,it is particularly important to find a more suitable detection method.In recent years,due to the influence of environment,diet and other factors,PP has a significant upward trend,and most of the children with PP have the phenomenon of overnutrition.Studies have shown that sex hormone binding globulin?sex hormone binding Globulin,SHBG?is negatively correlated with metabolic syndrome,obesity and insulin resistance,and SHBG is significantly decreased in the serum of patients with true precocious puberty.However,there is no relevant study on whether SHBG can be used as a diagnostic indicator in ICPP and PT,its sensitivity and specificity.The aim of the study is to explore the clinical value of SHBG combined with sex hormone in the identification of ICPP and PT.Methods:In this study,134 cases of ICPP group and 128 cases of PT group,who were diagnosed and treated in the endocrine clinic of Ganzhou Maternal and Child Health Care Hospital from April 2018 to July 2019,were collected as the study objects.Meanwhile,26 cases of normal adolescent girls?PC?and 68 cases of normal prepublity control?PPC?were selected as the control group.The serum levels of SHBG,FSH,LH,E₂ and PRL were measured by immunoluminescent assay.The differences of the results and the clinical diagnosis value were analyzed.Results:1.The SHBG level of ICPP group was significantly lower than that of PT group?P<0.01?,and the SHBG level of PT group was lower than that of PPC group?P<0.01?,but there was no significant difference in the SHBG level between ICPP group and PC?P>0.05?.2.The levels of LH,FSH and E₂ in ICPP group and PC group were higher than those in PT group and PPC group.The differences was significant?P<0.01?.2.There was no significant difference in the concentration of PRL among different groups?P>0.05?.3.When SHBG is used to predict ICPP?its cut-off value is 72.22nmol/L?,the predictive diagnostic sensitivity and specificity are respectively 0.778 and 0.985?AUC=0.986?,respectively;when FSH is used to predict ICPP?its cut-off value is2.395?,the predictive diagnostic sensitivity and specificity are respectively 0.683 and0.738?AUC=0.746?,respectively;when LH is used to predict ICPP?its cut-off value is 0.205 U/L?,the predictive diagnostic sensitivity and specificity are 0.675 and0.985?AUC=0.973?,respectively;when E₂ is used to predict ICPP?its cut-off value is 24.4 pg/mL?,the predictive diagnostic sensitivity and specificity are 0.742 and0.759?AUC=0.818?,respectively.The AUC of SHBG,FSH,LH and E₂ in serum was more than 0.5,especially that of SHBG and LH was more than 0.9,which had high sensitivity and specificity,and had obviously clinical diagnostic value.Conclusions:The serum SHBG level of children with ICPP is significantly lower than that of girls with PT and PPC.Clinically,SHBG combined with traditional sex hormone detection can distinguish the situation of precocious puberty better.