Left abdominal pain and blood in the urine may be related to the upper urinary tract. When upper urinary tract stones are present, patients experience pain in the lower back and left abdomen. The degree of pain depends on the size and location of the stone; large stones in the renal pelvis are less painful, appearing as a dull or vague ache; small stones are more mobile in the kidney and therefore often cause severe renal colic, which can last from a few minutes to several hours. Ureteral stones are more painful and may be accompanied by radiating pain in the urethra and head of the penis. There is usually microscopic haematuria, but hematuria in the naked eye is rare. Prompt medical attention is recommended. In addition to blood and urine tests, the doctor will usually recommend ultrasound and x-ray to clarify the condition.