@ imatine - Sorry for butting in here! To find out if you have E.coli in your blood, you will have to have a blood culture - where they will watch for bacteria growth over 2-3 days. There is usually fever present too. E.coli in urine is probably more common. You will need a urine culture for this. With the symptoms you have, this could be a possibility. If a urine E.coli infection is severe, it can enter the blood stream- especially if your immune system is weakened, similar to Marvin.