Study subjects and sample collection
This study included subjects aged 20 to 45 years who individuals with VVC and normal controls. Clinical samples from female patients attending the Department of Gynecology of Tongren Hospital were randomly collected, and 14 VVC-diagnosed patients and 15 normal controls were recruited after vaginal discharge testing. All individuals were informed and provided written informed consent, and the study was approved by the Ethics Committee of Tongren Hospital, Shanghai Jiao Tong University. The participants were screened, women who were pregnant, postmenopausal, menstruating, taking antibiotics and antifungals during the first three months of the study, using vaginal rinse during the first three weeks of the study, having sexual intercourse or using vaginal lubricants within 48 hours prior to sample collection were excluded from the study.
Samples of vaginal discharge from 29 subjects were collected on sterile cotton swabs, two samples per person, half of which were made into smears for Gram stain and sent to the Department of Clinical Laboratory, Shanghai Tongren Hospital for examination. The other half collected cotton swabs from the vaginal discharge of the study participants were added with 0.3mL solvent (methanol) containing internal standard (4ug/mL, L-2-chloro-phenylalanine), and were clarified by centrifugation (13000rpm for 10 min at 4°C). Frozen 200uL of supernatant at -80°C for subsequent global metabolomics identification and quantification analysis.