Hello, This is my first time using a web site like this but umm my 19 year old boy friend has been urinating blood for the past 2 months with horrible low back pain . The doctors are having a hard time diagnosing a problem... They ve ruled out cancer, kidney stones , urinary infections ect.. They are focusing on some type of kidney infection . I m quit knowledgeable on the topic of anatomy and was courious if it is a possible renal infection, but I feel like if that s what it was they would have figured that our by now... And he is a very active person, in shape and is very frustrated with his situation