Recovery phase from pyelonephritis. Tia!

Hi Doctor, My mother had pyelonephritis and have kept Dj stent and removed it as part of treatment it been a month stent has been removed and she is under medication and at the stent of stent removal doctor bladder has bit swelling and she is under medication for all now she is getting foam like bubbles while passing urine mostly in midnight or early morning if she pee for every 2hrs its normal and if she pass urine at 3hrs bit bubbles are coming but that is very light but at mid night and early morning bubbles are bit more comparatively but if she go pee for every 2hrs no issues She won't have other new symptoms like fever, high BP, fatigue, vomitings, lega and hands swelling, back pain etc she won't have all these only bubbles while passing urine that to if she didn't pass urine for 3hrs or more if she goes for every 2hrs everything is fine. Now our concern is it related to kidney dysfunctional or damaged or any other UTI was worried about it can you please help here. TIA