Biomarker Panel for PCOS-Associated Liver Steatosis in Adolescent Girls (COMPASS-pedPCOS)

This single-center, prospective, observational, cross-sectional mechanistic pilot study will evaluate whether polycystic ovary syndrome (PCOS) contributes to hepatic steatosis in adolescent girls independently of adiposity. A total of 150 girls aged 10-18 years will be enrolled into three groups of 50: girls with PCOS and obesity, age- and body mass index-matched girls with obesity but without PCOS, and healthy normal-weight girls. Each participant will undergo a single evaluation comprising anthropometry, clinical and biochemical phenotyping, transient elastography with controlled attenuation parameter and two-dimensional shear wave elastography, and a single venous blood sample. An extended biomarker panel will be measured by enzyme-linked immunosorbent assay (Fetuin-A, fibroblast growth factor 21, adiponectin, visfatin, cytokeratin-18 M30 and M65, soluble CD163, growth differentiation factor 15, 11-ketotestosterone, and 11beta-hydroxyandrostenedione), together with liquid chromatography-tandem mass spectrometry measurement of testosterone and sex hormone-binding globulin, and genotyping of PNPLA3 rs738409 and HSD17B13 rs72613567. The primary objective is to compare hepatic steatosis and the hepatokine/adipokine profile between the PCOS with obesity group and the adiposity-matched obesity control group, adjusting for body mass index z-score, insulin resistance, and free androgen index. No therapeutic intervention is assigned by the study protocol.

Inclusion Criteria: * Female, aged 10 to 18 years, with written informed consent from a parent or legal guardian and written assent from the child. * Group 1 (PCOS with obesity): both hyperandrogenism and oligo-anovulation required, based on adolescent-adapted Rotterdam criteria; body mass index at or above the 95th percentile. * Group 2 (Obesity control): body mass index at or above the 95th percentile, without features of PCOS, matched to Group 1 for age and body mass index. * Group 3 (Healthy control): healthy normal-weight girls (body mass index between the 5th and 84th percentile) without chronic disease, hyperandrogenism, or menstrual irregularity. Exclusion Criteria: * Known acute or chronic liver disease (including viral, autoimmune, or Wilson disease) or use of hepatotoxic medication. * Endocrine disorders or secondary hyperandrogenism, including Cushing syndrome, hypothyroidism, uncontrolled diabetes mellitus, congenital adrenal hyperplasia, androgen-secreting tumour, or hyperprolactinaemia. * Syndromic or monogenic obesity (including Prader-Willi syndrome, Bardet-Biedl syndrome, Alström syndrome, MC4R or LEP variants) or a known genetic disorder. * Use of relevant or hepatotoxic medication within the preceding three months, including corticosteroids, metformin, oral contraceptives, valproic acid, or antiandrogens. * Pregnancy or regular alcohol use. * Refusal of consent or assent.