Pheloboliths are what radiologist call stones - the term "lith" translated means stone. Yes they can cause flank pain and other problems too.
Is it dangerous to have multiple phleboliths with just one kidney?
Not necessarily dangerous as long as you have flow from the kidney and this can be seen on a cystoscopy, VCUG, or a contrast CT scan - but if you have pain, and the flow from the kidney is block for an extensive period of time, then the kidney can die - but you can help yourself by stay well hydrated - as most stones will pass. I hope this helps and thank you for the accept.