<s>[INST] What is an acceptable wait time for surgery removal of a 8mm kidney stone? There was a kidney infection, 7days antibiotics, and they put in a stint, why not just do IV antibiotics and get it out instead of placing a stint? They are waiting 21 days from the stint placement which has now led to a UTI, just need some clarity. [/INST] Hi,Placing a stent will help the ureter get passively dilated and this will make the stone removal process much easier and safer when the endoscope is passed later. This dilatation usually takes place gradually over two to three weeks.Removal of a stone in the presence of active infection is not usually recommended. You should be under the cover of good antibiotics till the stone is removed. </s>