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the finding of multi cystic dysplastic kidney
in one kidney will not harm your sister, she can lead a normal life provided her other kidney is functioning well, she need not worry, if the other one also has cysts, she has to go for routine check up and tests to monitor her renal functions
She can get symptoms like fever
, etc indicating a urine infection, increased urination , reduced urination , pain in the back/abdomen are some significant symptoms during which she needs medical attention