Porpon RotjanapanAunyakant JaroensukrungruangPrapaporn PisitkunPintip NgamjanyapornJittima ManonaiVorthon SawaswongPrangwalai ChanchaemSunchai PayungpornChulalongkorn UniversityFaculty of Medicine Ramathibodi Hospital, Mahidol University2022-08-042022-08-042021-10-27Lupus Science and Medicine. Vol.8, No.1 (2021)205387902-s2.0-85118845316https://repository.li.mahidol.ac.th/handle/20.500.14594/77203Objective The risk factors associated with urinary tract infections (UTIs) in patients with SLE remain uncertain. We evaluated the vaginal microbiota pattern and its potential UTI-associated risk factors. Methods A pilot cross-sectional study of patients with SLE was conducted at Ramathibodi Hospital, Bangkok, Thailand, during 2019-2020. Patients' demographic data and relevant information were collected. Vaginal microbiota was assessed in all patients and in 10 healthy volunteers. Results Fifty-two patients were enrolled (mean age: 46.1 years). All patients had SLE that was in low disease activity. As per the Simpson_e index, the within-group alpha diversity of the vaginal microbiota was low in the SLE with UTI and SLE receiving trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis groups. Multivariate logistic regression analysis revealed that TMP-SMX prophylaxis (adjusted OR (AOR), 30.96; 95% CI 3.63 to 264.11; p=0.002), elevated C3 levels (AOR, 35.33; 95% CI 1.33 to 936.67; p=0.033) and presence of Veillonella dispar in the vaginal microbiota (AOR, 6.68; 95% CI 1.27 to 35.07; p=0.025) were associated with UTI. Conclusions The vaginal microbiota diversity differed between patients with lupus with and without UTI, and unnecessary administration of TMP-SMX prophylaxis may affect the alpha diversity of the vaginal microbiota.Mahidol UniversityImmunology and MicrobiologyArticleSCOPUS10.1136/lupus-2021-000551