I have low pH urine and ketone shedding in urine (sometimes moderately high levels of ketones, without any change in diet so is not due to that) when I have SIBO (small intestine bacterial overgrowth) flares. I was diagnoised with SIBO at Cedars-Sinai several months ago after doing hydrogen breath test (lactulose), which was ordered by my G/I. Something to consider.