Had urine culture and found e.coli. is it due to stds, stis or utis? how it can be treated and if left untreated what are the complications?

Ecoli UTI: This sound like you have an E. Coli urinary tract infection. This is not sexually transmitted. It is an infection in the bladder and it must be treated with antibiotic. If it is not treated the infection can go from bladder to ureters to kidneys and cause a much more serious kidney infection called pyelonephritis. This could require hospitalization. Please get treated right away