Factors associated withEntamoeba histolyticaproctocolitis in men who have sex with men: a systematic review

ObjectiveEntamoeba histolyticais parasitic infection that can cause a proctocolitis (amoebiasis) and extraintestinal sequelae (eg, liver abscess) and can be sexually transmitted in men who have sex with men (MSM). We aimed to identify factors associated withE. histolyticain MSM to provide insight for future control strategies.Design/methodsWe searched MEDLINE, Embase, CINAHL and Web of Science Core Collections for manuscripts published up to November 2022. One author screened abstracts; two authors independently conducted a full-text review. We included manuscripts that contained primary data on factors associated with transmission in MSM. Quality and risk of bias were assessed independently by two authors using the Joanna Briggs Institute critical appraisal tools. We used the nine-point synthesis method to synthesise narrative data.ResultsNine manuscripts consisting of 832 individuals withE. histolyticawere included; six cross-sectional studies, two case-control studies and one cohort study.E. histolyticain MSM was associated with: increasing age, transmission in warm seasons, lower educational achievement, concurrent sexually transmitted infection (STI) (Treponema pallidum,Neisseria gonorrhoeae,Chlamydia trachomatis), hepatitis B core antibody positivity, hepatitis C antibody positivity, concurrent sexually transmitted enteric infection (Shigellaspp,Giardia duodenalis), having a previous STI (T. pallidum, N. gonorrhoeae), oral-anal sex, exclusively/majority receptive anal sex and having an increased number of sexual partners.ConclusionThis review has highlighted some important demographic, biological and behavioural factors associated withE. histolyticain MSM which can inform future clinical guidelines and public health control strategies.PROSPERO registration numberCRD42022366168.