Journal article

Factors associated with rectal pH among men who have sex with men

Fabian YS Kong, Jacqueline Woutersen, Michelle M Kroone, Jane S Hocking, Henry JC de Vries



Background Rectal chlamydia treatment failures up to 22% with azithromycin 1 g have been reported, but low tissue concentrations are unlikely to be the cause. Anecdotally, low rectal pH could reduce rectal azithromycin concentrations, with in vitro studies reporting higher minimum inhibitory concentrations (MICs) with lower pHs for antibiotics used to treat sexually transmissible infections (STIs). Leucocytes arising from an inflammatory immune response could also lower pH and efficacy. We examined factors that may alter rectal pH and potentially influence treatment outcomes. METHODS: We recruited consecutive men who have sex with men (MSM) from a Dutch STI clinic between October 2016 and Ju..

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Awarded by NHMRC

Funding Acknowledgements

FYSK was funded by an Endeavour Research Fellowship from the Australian Government Department of Education and Training. JSH is supported by a NHMRC Senior Research Fellowship (1136117). Waiver of patient consent was granted through the Medical Ethics Committee (Amsterdam Medical Centre; MEC number W12_087#2.17.0105).