Blood in your urine is always something that should be investigated (because it shouldn't be there), but it doesn't signify pyelonephritis. It can just be the irritation/inflammation in the urethra/bladder. Can be from kidney stones. Can be from renal cancer. Depends on how much blood and what it looks like under the microscope (intact red blood cells usually indicate the blood is from lower down the renal tract, if the cells look mangled they are probably from the kidney).
Also she is WAY too fat for an ultrasound. Ultrasounds are great but they can only see through so much before the picture starts to degrade. You are getting a picture from sending sound waves to an object and reading the sound wave that returns. Anything beyond 10-15cm or so the image isn't great. As a Sonographer would note, "poor image quality due to body habitus" (which is polite medical speak for "patient was too fat, this was a waste of time").