The prevalence of ZnT8A in Thai juvenile-onset T1DM appears to be higher than in previous studies from Asia. ZnT8A could replace IA2A as an autoimmunity marker in Thai pediatric T1DM patients with better diagnostic performance. This article is protected by copyright. All rights reserved.

BackgroundThe criterion standard gonadotropin-releasing hormone (GnRH) stimulation tests to diagnose central precocious puberty (CPP) are time-consuming, inconvenient, and expensive.ObjectivesTo determine predictive cut-off values codetermined by ultrasonographic parameters and basal gonadotropin levels in girls with premature sexual development and compare them results of criterion standard tests in a study of diagnostic accuracy.MethodsRetrospective review of hormonal investigations and ultrasonographic uterine and ovarian parameters in a consecutive sample of girls at a single center, tertiary care hospital in Bangkok, Thailand.ResultsWe separated data from 68 girls (age range 2–12 years) into 2 groups based on their response to a GnRH analogue agonist stimulation test. A “prepubertal response” group included girls with premature thelarche and thelarche variants (n = 18, 6.37 ± 1.77 years) and a “pubertal response” group, including girls with CPP (n = 50, 8.46 ± 1.46 years); excluding patients with pathological causes (n = 0). The basal level of luteinizing hormone (LH) had the largest area under receiver operating characteristic curves (AUC) of 0.84; 95% confidence interval [CI] 0.74–0.93) compared with basal levels of follicle stimulating hormone (AUC 0.77; 95% CI 0.64–0.90) or estradiol (0.70; 95% CI 0.56–0.85). An optimal cut-off of 0.25 IU/L LH was related to a pubertal response to GnRH analogue agonist stimulation tests with 75.0% sensitivity, 88.9% specificity, 94.7% positive predictive value (PPV), and 57.1% negative predictive value. Uterine and ovarian cut-off volumes of 3.5 cm3 and 1.5 cm3 were related to a pubertal response with 88.6% and 76.2% PPV, respectively. A uterine width cut-off of 1.7 cm combined with a basal LH cut-off of 0.25 IU/L increased specificity and PPV to 100%.ConclusionCombining uterine and ovarian ultrasonographic parameters with basal gonadotropin levels, especially uterine width and basal LH level, appears useful for diagnosis of CPP.