ESPE Abstracts

Background: Adolescent polycystic ovary syndrome (PCOS) may be difficult to distinguish from pubertal changes and diagnosis remains a challenge.

Objective and hypotheses: To investigate the value of different biochemical parameters for the diagnosis of PCOS and also to assess the prevalence of non-classical congenital adrenal hyperplasia (NCCAH) among adolescent girls referred for clinical symptoms suggesting PCOS.

Method: Retrospective data of 114 girls aged 13–18 with a clinical presentation suggesting PCOS were analysed, including results of basal androgens, prolactin, GnRH and ACTH stimulation tests, and pelvic ultrasound. Clinical and laboratory characteristics of girls diagnosed with PCOS (based on Rotterdam criteria) were compared to those of girls having ‘Isolated’ hyperandrogenism or menstrual irregularities (‘non-PCOS’).

Results: Of the 114 girls, 9 (7.9%) were diagnosed with NCCAH and 87 with PCOS; 18 were non-PCOS. Compared to non-PCOS girls, those with PCOS had a significantly higher prevalence of hirsutism (P<0.002), PCO morphology by ultrasonography (P<0.001), menstrual irregularities (P<0.001) and acne (P<0.001). Androstenedione, (P<0.01), basal LH (P<0.02) and basal LH/FSH ratio (P<0.002) were significantly higher in girls with PCOS, but overlap between groups was observed. Peak LH/FSH ratio was similar in both groups. There were no significant differences between the subgroups in any other biochemical or anthropometric parameters. Using stepwise logistic regression, the only predictive factor for PCOS was the basal LH/FSH ratio, with insufficient sensitivity and specificity.

Conclusion: While an increased basal LH and basal LH/FSH ratio may support the diagnosis of PCOS in adolescents, the GnRH stimulation test is not contributory. Given the significant prevalence of NCCAH among adolescents presenting as PCOS, an ACTH test should be included in the work-up, at least in populations with higher prevalence. Since no one parameter is diagnostic for PCOS, clinical criteria remain paramount.