Blood in the Urine: Hematuria

Seeing blood in your urine is never normal. While in many instances there are benign causes, blood in urine or hematuria can also indicate a serious disorder.

Blood that you can see is called "gross hematuria". Urinary blood that's visible only under a microscope is known as "microscopic hematuria" and is found when your doctor tests your urine. Either way, it's important to determine the reason for the bleeding. Treatment will depend on the underlying cause.

Symptoms of Hematuria:

The visible sign of hematuria is pink, red or cola-colored urine — the result of the presence of red blood cells. It takes very little blood to produce red urine, and the bleeding usually isn't painful. If you're also passing blood clots in your urine, that can be more symptomatic. Bloody urine often occurs without any other signs or symptoms.


When to see a doctor?

Make an appointment to see your doctor anytime you notice blood in your urine. Even if it is only a small amount and disappears on it's own. Blood in the urine is never normal. 

A change in urine color caused by drugs, food or exercise may go away within a few days. But you can't automatically attribute red or bloody urine to medications or exercise; that's why it's best to see your doctor anytime you see blood in your urine.


For some people, especially older adults, the only sign of illness may be microscopic blood.

Causes of Hematuria:

When hematuria is present, red blood cells are leaking into the urine from somewhere in your urinary tract. It can come from either the kidneys, ureters, bladder or urethra. 

A number of conditions can cause blood in the urine, including:

• Urinary tract infections. The inflammation of the bladder lining from bacterial infection can allow the wall to bleed easily. Symptoms can include a persistent urge to urinate, pain and burning with urination, and extremely strong-smelling urine.

• Kidney infections. Kidney infections, called pyelonephritis, can occur when bacteria enter your kidneys from your bloodstream or migrate up from your bladder to your kidney. Signs and symptoms are often similar to bladder infections, though kidney infections are more likely to cause fever and flank pain. The lining of the collecting system within the kidney becomes inflamed and can bleed easily.

• A bladder or kidney stone. The minerals in concentrated urine sometimes precipitate out, forming crystals on the walls of your kidneys or bladder. Over time, the crystals can continue to bind more crystals, becoming a stone. The stones that are just sitting in the kidney are generally painless, and you probably won't know you have them. Kidney stones cause pain when they attempt to pass down the ureter where they can cause obstruction. The scratching and inflammation of a stone passing can cause either visible or microscopic bleeding.

• Enlarged prostate. The prostate gland often begins growing as men approach middle age. When the gland enlarges, it compresses the urethra, partially blocking urine flow. 
  Signs and symptoms of an enlarged prostate (benign prostatic hyperplasia, or BPH) include difficulty urinating, an urgent or persistent need to urinate, and either visible or microscopic blood in the urine. Infection of the prostate (prostatitis) can cause the same signs and symptoms.
  
  
• Kidney disease. Microscopic urinary bleeding is a common symptom of glomerulonephritis, which causes inflammation of the kidneys' filtering system.
  Glomerulonephritis may be part of a systemic disease, such as diabetes, or it can occur on its own. It can be triggered by viral or strep infections, blood vessel diseases (vasculitis), and immune problems such as IgA nephropathy, which affects the small capillaries that filter blood in the kidneys (glomeruli).
  
  
• Cancer. Visible urinary bleeding may be a sign of kidney, bladder or prostate cancer. This may be the only sign or symptom in the early stages.

• Inherited disorders. Sickle cell anemia — a hereditary defect of hemoglobin in red blood cells — can be the cause of blood in urine, both visible and microscopic hematuria. So can Alport syndrome, or any kidney disease which affects the filtering membranes in the glomeruli of the kidneys.

• Kidney injury. A blow or other injury to your kidneys from an accident or contact sports can cause blood in your urine that you can see.

• Medications. Visible urinary blood sometimes occurs if you take any blood thinners, such as aspirin, coumadin or plavix.

• Strenuous exercise. Runners are most often affected, although almost any athlete can develop visible urinary bleeding after an intense workout. 

Whatever the cause, contact your doctor right away if you see blood in your urine.


Risk Factors for Hematuria:

Almost anyone — including children and teens — can have red blood cells in the urine. Factors that make this more likely include:

• Age. Many men older than 50 have occasional hematuria due to an enlarged prostate gland.
• Your sex. More than half of all women will have a urinary tract infection at least once in their lives, possibly with some urinary bleeding. Younger men are more likely to have kidney stones or Alport syndrome, a form of hereditary nephritis that can cause blood in the urine.
• A recent infection. Kidney inflammation after a viral or bacterial infection (post-infectious glomerulonephritis) is one of the leading causes of visible urinary blood in children.
• Family history. You may be more prone to urinary bleeding if you have a family history of kidney disease or kidney stones.
• Certain medications. Aspirin, nonsteroidal anti-inflammatory pain relievers and anticoagulants are known to increase the risk of urinary bleeding.
• Strenuous exercise. Long-distance runners are especially prone to exercise-induced urinary bleeding. In fact, the condition is sometimes called jogger's hematuria. But anyone who works out strenuously can develop symptoms
• Environmental Toxin Exposure: Hair dye, chemicals in your personal care products, preservatives and dyes in foods, inhalation exposure on the job, smoking. Read your labels and know what you are exposing yourself to on a daily basis! 

Testing and Diagnostics:

To find a cause for urinary bleeding, the following tests and exams play a key role:

• Physical exam, which includes a discussion of your medical history.
• Urine tests. Even if your bleeding was first discovered through urine testing (urinalysis), you're likely to have another test to see if your urine still contains red blood cells. Urinalysis can also check for urinary tract infection or the presence of crystals that cause kidney stones.
• Imaging tests. Often, an imaging test is required to find the cause of hematuria. Your doctor might recommend a computerized tomography (CT) scan, which uses radiation and a computer to create cross-sectional images of the inside of the body; magnetic resonance imaging (MRI), which uses a magnetic field and radio waves instead of X-rays to produce images; or an ultrasound exam. Ultrasound uses a combination of high-frequency sound waves and computer processing to produce images of your kidneys and bladder.
• Cystoscopy. In this procedure, your doctor threads a narrow tube fitted with a tiny camera into your bladder to closely examine both the bladder and urethra for signs of disease.

Sometimes, the cause of urinary bleeding may not be found. In that case, your doctor may recommend regular follow-up tests, especially if you have risk factors for bladder cancer, such as smoking, exposure to environmental toxins or a history of radiation therapy.


Treatment for Hematuria:

Hematuria has no specific treatment. Instead, your doctor will focus on treating the underlying condition. This might include, for instance, taking antibiotics to clear a urinary tract infection, trying a prescription medication to shrink an enlarged prostate, or the treatment of bladder or kidney stones.


Prevention of Hematuria:

It is generally not possible to prevent hematuria, though there are steps you can take to reduce your risk of some of the diseases that cause it. Prevention strategies include:

• Urinary tract infections. To reduce your risk of urinary tract infections, try drinking plenty of fluids, urinating when you feel the urge and after intercourse, and wiping from front to back after urination (for women). Avoid feminine hygiene products that may irritate you.
• Kidney stones. To help lower the likelihood of kidney stones, drink plenty of fluids and limit salt, protein and oxalate-containing foods, such as spinach.
• Bladder cancer. Quit smoking, avoiding exposure to chemicals and drinking plenty of fluids can cut your risk of bladder cancer.
• Kidney cancer. To help prevent kidney cancer, stop smoking, maintain a healthy weight, eat a healthy diet, stay active and avoid exposure to toxic chemicals.