What Can Cause Blood in Urine (Without an Infection)?

Blood in urine is a symptom that does not typically appear on its own, and is generally a sign of an underlying problem. It is important to understand that the cause of blood in urine is not always infection. There are multiple causes for this, some more serious than others. Possible causes of blood in urine besides infection are:

• Medications

Blood-thinning medicines like aspirin and warfarin are useful in dissolving blood clots, but can also push microscopic traces of blood into a person's urine. Prolonged usage of Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) like ibuprofen can also cause blood to appear in someone's urine.

• Internal Hemorrhaging

Trauma, injury, and overexertion during exercise may all cause internal injuries that break blood vessels. This can cause blood to leak into body cavities and discharge in a patient's urine. A blow to the kidneys might also rupture cell walls and blood vessels, therefore causing bleeding during urination. Hemorrhaging may also occur when an aneurysm or balloon-like expansion of an abdominal artery ruptures.

• Stones in the Kidney or Ureter

Intense dehydration due to a lack of proper water intake decreases a person's urine output. This situation can create acidic conditions within the entire urinary system, paving the way for the growth of crystalline calculi that harden and form stone-like masses within the person's kidneys. The passage of these stones through the ureter and out through the urethra is often agonizingly painful experience. These stones can also rip into the epithelial cell walls that line the ureter and bladder, thereby releasing blood into the urine.  

• Prostate Problems

In men, the prostate gland opens near the area where the bladder discharges urine into the urethral tube. This gland secretes seminal fluid which becomes the nutrient-rich medium for carrying sperm. The gland may become enlarged or dysfunctional, a condition common in elderly males. Cancerous growths can also damage healthy prostate tissue and cause blood in a man's urine.

• Cancers of the Urinary Tract

In the excretory system, cancer may develop in any of three places – the kidney, ureter or urinary bladder. Abnormal cells in these areas grow uncontrollably and create large tumors, or masses of dysfunctional tissue that destroy healthy cells. Bleeding is one of the symptoms that can result from cancers of the urinary tract. Some other common symptoms include backache, abdominal pain, fatigue, and fluid retention. The presence of blood in urine is not usually associated with the early stages of cancer, as it is typically a symptom of advanced stage cancers. This is an important reason why those who notice blood in their urine should seek the advice of a specialist and schedule a cancer checkup.

• Genetically Acquired Diseases
  • Polycystic kidney disease: Fluid-filled sacs or cysts proliferate in the kidneys, pushing aside normal, healthy cells. In this condition, the kidneys become larger in size and often stops functioning properly. Bleeding in urine can also be one of the symptoms.
  • Hemophilia: This is an inherited disorder of the blood-clotting system. Blood clotting mechanisms are largely controlled by proteins. Any weakening of these proteins makes them incapable of clotting blood. Therefore, small cuts, bruises, and internal injuries take a long time to heal and stop bleeding quickly. If a hemophiliac becomes injured, there will likely be blood in their urine. 
  • Sickle cell disease: This disease gets its name from the peculiar sickle-shaped deformity of red blood cells in patients who suffer from it. The deformed red blood cells cause a lack of oxygen in patients, and can cause massive organ failure or intermittent bleeding through urine. Difficulty breathing, body pain, and fever are other symptoms.
  • Benign familial hematuria: This is a genetically acquired disorder where spherical bundles of capillaries supplying blood to the kidneys cause thinner membranes. Though not a life-threatening condition, a urinalysis of patients with the disease will often reveal traces of blood in the urine.