Background: The objective of the study was to explore the clinical significance of steroid hormones in the diagnosis of PCOS and PCOS‐related insulin resistance through liquid chromatography–mass spectrometry/mass spectrometry (LC–MS/MS) and chemiluminescent immunoassay (CLIA).Methods: The study included 114 patients with PCOS and 100 controls. Steroid hormone levels in serum were measured using LC–MS/MS and CLIA. The Bland–Altman method was used to check the consistency between the two methods. The diagnostic value of the LC–MS/MS method for female hyperandrogenemia and PCOS was evaluated.Results: Women with PCOS were younger than controls on average (p < 0.001). PCOS patients had higher luteal hormone (LH, p < 0.001), insulin (p = 0.002), estradiol (E2, p < 0.001), total testosterone (TT, p < 0.001), free androgen index (FAI, p = 0.021), dehydroepiandrosterone sulfate (DHEA, p = 0.021), insulin resistance index (HOMA‐IR) (p = 0.034), and fasting glucose (p = 0.017) levels than controls as measured by CLIA. The diagnostic value of TT was the best, and the area under the AUC curve was 0.766. Women with PCOS had higher androstenedione (A2, p < 0.001), FAI (p < 0.001), TT (p < 0.001), and 17‐hydroxyprogesterone (17‐OHP, p < 0.001) levels than controls as measured by LC–MS/MS. The ROC curve showed that the diagnostic efficacy of A2, TT, and 17‐OHP was 0.830, 0.851, and 0.714, respectively. The consistency of TT detected by LC–MS/MS and CLIA was poor according to the Bland–Altman method. Detected TT by LC–MS/MS had the highest diagnostic efficiency for PCOS. The diagnostic power of the LC–MS/MS results for PCOS‐related insulin resistance was analyzed. The results showed that the FAI had the highest diagnostic power, with an ROC curve of 0.798.Conclusion: LC–MS/MS is more sensitive and accurate than CLIA in the determination of serum TT and FAI. TT is more effective for the diagnosis of PCOS, whereas FAI is more valuable in the diagnosis of insulin resistance.

There is limited evidence linking antibiotic exposure, particularly from contaminated food or drinking water, to childhood obesity. The study aimed to investigate the association between urinary antibiotic levels and overweight/obesity in preschool children. In the case-control study, 121 overweight/obese preschoolers and 242 controls (aged 3-6 years) from eastern China were enrolled in 2022 based on age, sex, and study site matching. Overweight/obesity was determined using body mass index (BMI) and weight for height (WFH) criteria derived from national data. A total of 50 antibiotics from 8 categories were analyzed using ultra-performance liquid chromatography and tandem mass spectrometry (UPLC-MS/MS). We identified major dietary patterns using principal component analysis (PCA) and examined the associations of antibiotic exposure with childhood overweight/obesity using multivariate logistic regression. Twenty-four individual antibiotics were detected in more than 10 % of the samples, and overall detection rates were up to 100 %. Overweight/obese children had a higher exposure to veterinary antibiotics (VAs) than normal weight children. PCA analysis showed that children who were overweight/obese had higher scores of "Aquatic products preferred dietary pattern" and "Cereals preferred dietary pattern" compared to children with normal weight. Multivariate logistic regression analyses indicated that exposure to elevated levels of deoxytetracycline (OR: 1.72; 95 %CI: 1.00-2.93) and quinolones (OR: 1.63; 95 %CI: 1.04-2.57) was significantly related to an increased risk of BMI-based overweight/obesity. Quinolones exposure was also significantly associated with WFH-based overweight/obesity, primarily in boys. After adjustment for all covariates, higher exposure to ofloxacin (of the quinolones) was significantly related to overweight/obesity in girls. Exposure to certain antibiotics, especially quinolones, may increase the risk of overweight/obesity in preschoolers. More prospective, well-designed studies are needed to clarify these findings.