thank you for posting your query in healthcaremagic.com..... see traces of blood in kidney is not very alarming when associated with some infection etc and not many other urogenital symptoms....but sometimes it is associated with loin pain, urinary trouble etc...then a specialist consultation is advised.... and as for the ultrasound report, a hyperechoic lesion or mass in kidney can be benign mass, stones, calcification or calcified cysts, or even carcinoma or kidney cancer.....it depends upon age, sex, other relevant history, symptoms and after proper examination of the patient... so i would suggest you to consult an UROLOGIST asap.... hope this was useful... regards