What is blood in the urine or hematuria?

Blood in the urine, known as hematuria, can be unsettling to see. Hematuria means that red blood cells are present in the urine. Sometimes the urine looks pink, red, or brown, which is called visible or gross hematuria. Other times the blood is not visible to the eye and can only be detected through a urine test. This is called microscopic hematuria. Both types are important and should be taken seriously.

There are many possible reasons for blood to appear in the urine. Some causes are minor or temporary, while others may require medical evaluation and treatment. One common cause is a urinary tract infection. When bacteria irritate the bladder or urethra, tiny blood vessels can break, leading to bleeding. Other common causes include kidney stones. As stones move through the urinary tract, they may scratch or irritate the lining and cause bleeding.

Exercise can sometimes lead to temporary hematuria, especially after long-distance running. This type of bleeding is not usually harmful and often disappears without treatment. Dehydration may also make bleeding more noticeable because the urine becomes concentrated.

In some cases, hematuria may be linked to conditions affecting the kidneys, bladder, or prostate. These conditions may include inflammation, injury, structural abnormalities, or less commonly, cancer. While the possibility of cancer causes worry for many, hematuria does not automatically mean cancer. However, because blood in urine may be a sign of a more serious problem, it is important to investigate the cause.

A doctor often begins by asking questions about symptoms, recent illnesses, exercise habits, and medical history. A urinalysis is usually the first test performed. Depending on the findings, further tests such as an ultrasound, CT scan, cystoscopy, or blood tests may be recommended. These tests help determine whether the source of bleeding is the bladder, kidneys, prostate, or urinary tract.

Treatment depends on the cause. If a urinary infection is confirmed, antibiotics are usually effective. If kidney stones are responsible, treatment may range from increased hydration to procedures that help break or remove the stones. In cases related to underlying medical conditions, treatment focuses on managing the condition and preventing future bleeding.

Although seeing blood in the urine can be alarming, many causes are treatable, especially when identified early. Paying attention to symptoms and seeking medical advice when needed can help protect bladder and kidney health.

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