Diagnostic Value Of Basic Gonadotropin Value In Girls With Central Precocious Puberty

Objective: To explore the diagnostic value of serum basal gonadotropin levels in girls with central precocious puberty(CPP).Methods: From January 2017 to June 2018,159 girls with precocious puberty who were admitted to the outpatient department of endocrinology of Jinan Children’s Hospital were selected as research objects,among which 52 were CPP and 107 were premature thelarche(PT).The baseline values of luteinizing hormone(LH)and follicle stimulating hormone(FSH),peak GnRH stimulation test,bone age and pelvic ultrasound parameters were compared between the two groups.The relationship between each index and the peak value of GnRH excitation test was analyzed.The receiver’s working curve,ROC curve was used to analyze the diagnostic significance of each index for CPP,and the combined diagnostic significance of basic serum LH value,bone age and pelvic ultrasound for CPP.Results: 1.In the CPP group,LH basic value,FSH basic value,LH peak value,LH peak value /FSH peak value,bone age,the difference between bone age and actual age,bone age index,uterine length and average ovarian volume were all significantly greater than those in the PT group.The difference was statistically significant(P<0.05).There were no significant differences between the two groups in FSH peak value,LH base value /FSH base value,maximum follicle diameter and total number of follicles(P > 0.05).2.The results of Spearman correlation analysis showed that the basic value of LH was positively correlated with the peak value of LH.Bone age index was positively correlated with LH peak and LH peak /FSH peak.the uterine length and the average ovarian volume were positively correlated with the peak value of LH and the peak value of LH/FSH(P <0.05).There was no correlation between FSH base value and FSH peak value(P>0.05).3.ROC curve analysis showed that LH basic value,FSH basic value,LH peak value,LHpeak value /FSH peak value,the difference between bone age and actual age,uterine length,and average ovarian volume were of diagnostic value for CPP,among which LH peak,LH peak/FSH peak had the highest diagnostic value,followed by the average ovarian volume,and the LH base value had the lowest diagnostic value.The average ovarian volume threshold was 2.35 ml,the sensitivity was 65%,the specificity was 73%;the critical value of bone age difference was 1.03 years,the sensitivity was 100%,the specificity was 47%;The critical value of uterine length was 2.65 cm.The sensitivity and specificity were 65% and66% respectively;When the basic value of FSH was > 2.47IU/L,the sensitivity and specificity were 64% and 70% respectively.When LH basic value was > 0.28IU/L,the sensitivity was 50%,but the specificity reached 73%;According to the results of GnRH stimulation test,159 girls were divided into positive group(71 cases)and negative group(88 cases).The cut-off point of basic LH value was 0.085IU/L,with a sensitivity of 79%and a specificity of 48%.For both the diagnostic value of CPP and GnRH stimulation test positive group,when the basic serum LH was taken as>1.8IU /L,the specificity the specificity was >95%(P<0.05).4.The ROC curve was used to diagnose the serum LH and the average ovarian volume.The area under the curve(AUC)was 0.70.The sensitivity and specificity were 62% and 75% respectively.The combined diagnosis of serum LH baseline value and bone age difference showed that AUC was 0.72,sensitivity and specificity were100% and 43% respectively.When the three indicators were combined for diagnosis,the AUC was 0.724,with a sensitivity of 83% and a specificity of 63%,indicating that the diagnosis was valuable(P<0.05).Conclusion: The basal serum LH value can be used as an primary screening index for the diagnosis of CPP girls.Combined with bone age and pelvic ultrasound has higher diagnostic sensitivity.