My father had PCNL for kidney stone. aa tube was placed in back side with a hole, this tube was removed on surgery day. a stent and a catheter is stilll inside. sometimes during sitting on the lavatory sheet some urine is leaked from catheter side and sme drops are leaked from the wound hole. we are doing the dressing regularly. the culture test of urine is negative. antibiotic is going on. i want to know why the watery thing is still coming from the back side incision hole. please guide. thank you in advance.