Basal Luteinizing Hormone/Follicle Stimulating Hormone Ratio in Diagnosis of Central Precocious Puberty
VI CHIT SUPORNSILCHAI, MD*, PARA VEE HIRANRAT , MD*, SUTTIPONG WACHARASINDHU, MRCP*, SUMARLEE SRIVUTHANA, MD*, SUPHAB AROONPARKMONGKOL, BSc*
Affiliation : * Endocrinology Unit, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand.
Objective : To evaluate the basal luteinizing hormone (LH)/follicle stimulating hormone (FSH) ratio in diagnosis of central precocious puberty in order to save time and cost.
Subjects and
Method : The GnRH stimulation tests were performed on 51 girls with breast development before 8 years old. The 51 girls were divided into 2 groups, 24 girls with central preco cious puberty (CPP) and 27 girls with premature thelarche (PT), and the clinical data and GnRH stimu lation tests data were compared between the 2 groups. The authors also compared the clinical data and GnRH stimulation tests data between 13 girls with PT and 12 girls with thelarche variants (TV) who developed puberty approximately I year later as confirmed by GnRH stimulation test.
Results : Girls with CPP had a large bone age and chronological age ratio and advancement of breast staging. Girls with TV had a greater level of basal luteinizing hormone (LH), peak LH and 120 min estradiol than girls with PT. Basal luteinizing hormone and follicle stimulating hormone (FSH) ratio greater than 0.2 can be used to diagnose CPP with 75 per cent sensitivity, 85 per cent specificity, 82 per cent positive predictive value (PPV) and 82 per cent negative predictive value (NPV)
Conclusion : Girls with CPP have a basal LH/FSH ratio greater than 0.2 and this can be used as a cut-off point for the diagnosis CPP.
Keywords : Central Precocious Puberty, Premature Thelarche, Thelarche Variants, Follicular Stimula ting Hormone, Luteinizing Hormone, Bone Age and Chronological Age
