Many people worry when they see blood in their urine. While it is certainly not a normal occurrence, it does not always mean that you have kidney cancer. There are numerous potential causes of blood in the urine, including infections, stones, and injuries.

In this article, OncoCare Cancer Centre breaks down the possible causes for this condition and the other symptoms of kidney cancer to help readers gain a clearer picture of what might be causing blood in the urine.

What Does it Mean if Blood Comes Out of Your Urine?: Understanding Haematuria

Blood in urine, also known as haematuria, can occur in both males and females when the kidneys or other areas of the urinary tract cause red and white blood cells to appear in the urine. But fret not because most people feel no pain when they experience haematuria.

Haematuria can manifest in two ways: visibly or microscopically.

In some cases, the blood in the urine is apparent, colouring the toilet water shades of red or pink or leaving noticeable spots after urination. In other instances, the blood cells are so sparse that they only become evident under laboratory examination.

Types of Blood in the Urine

Blood in the urine can be classified into three main types: gross, microscopic, and dipstick haematuria.

• Gross Haematuria: This form is visible to the naked eye. Urine may appear pink, red, or even have a cola-like colour if a significant amount of blood is present, making this type of haematuria the most noticeable.
• Microscopic Haematuria: Here, blood cells are present in the urine but in such small quantities that they can only be detected through microscopic examination. This type might go unnoticed without specific tests.
• Dipstick Haematuria: Often discovered during routine urine tests, this type occurs when a chemical reaction on a urine dipstick causes a colour change, which may or may not indicate the actual presence of blood cells. It's noted for its potential for false-positive results, where the test indicates haematuria even when blood cells are not present in the urine.

What is the Most Common Cause of Blood in the Urine?

While kidney cancer is one possible cause of blood in the urine, it is not the only one. A multitude of issues can cause this condition, such as:

• Infections: Urinary tract infections (UTIs) happen when bacteria make their way into the body through the urethra and start to multiply in the bladder. Symptoms might include needing to urinate all the time, pain and burning when urinating, and urine that smells very bad. For some people, especially older adults, the only sign of illness might be tiny amounts of blood in the urine.
• Kidney infections: Also known as pyelonephritis, it happens when bacteria get into your kidneys from your bloodstream or enter through your ureters to your kidneys. Other than haematuria, kidney infections can result in fever and flank pain too.

• Bladder or kidney stones: The minerals in urine can crystallise on the walls of your kidneys or bladder and form small, hard stones. In cases where they cause a blockage, bladder or kidney stones can result in blood in urine when being passed.

• Enlarged prostate: The prostate gland, located below the bladder and surrounding the urethra, often swells in size for middle-aged males. This can cause compression of the urethra and blockage of the free movement of urine. Consequently, this can lead to finding it hard to urine, constantly needing to relieve oneself, and blood in the urine.
• Kidney disease: Blood in the urine can also be caused by glomerulonephritis, which occurs when the kidneys' filtering system is inflamed.
• Hereditary disorders: Sickle cell anaemia, a problem with haemoglobin in the red blood cells, can cause blood in the urine. Alport syndrome is another inherited condition that affects the filtering membranes in the kidneys and can also lead to haematuria.
• Physical trauma: If your kidneys are hurt in an accident or from playing a contact sport, you may see blood in your urine.

• Medications: Also, certain medications, such as the chemotherapy drug cyclophosphamide, used to treat cancers like multiple myeloma, sarcoma, and breast cancer, and the antibiotic penicillin, used to treat many types of bacterial infections, can cause haematuria. For those experiencing conditions that will cause their bladders to bleed, taking anticoagulants like aspirin and blood thinners such as heparin can lead to blood in urine too.

• Cancer: Unfortunately, if you see blood in your urine and it is not caused by any of the aforementioned reasons, it could also be a sign of cancer in the kidney, bladder, or prostate. This is why it is essential to understand the symptoms of kidney cancer as well as to shed light on the true cause of your haematuria.

What Are the Signs and Symptoms of Haematuria?

Haematuria can manifest as pink, red, or even cola-coloured urine. The presence of even a minimal amount of red blood cells is enough to alter the colour of your urine significantly. Typically, this symptom isn’t associated with pain, although passing blood clots can be uncomfortable.

It is crucial not to confuse haematuria with blood that may seem to be in the urine but is actually coming from other sources. In females, this could be from the vagina, and in men, it could be due to ejaculation problems often linked to prostate issues. Additionally, blood from a bowel movement can sometimes be mistaken for blood in the urine.

Risk Factors of Developing Haematuria

Haematuria can affect anyone, from children to adults. Some factors that may increase the likelihood of this condition include:

• Age: Particularly in middle-aged and older men, an enlarged prostate can lead to haematuria.
• UTIs: UTIs are common causes of visible blood in urine, especially in children.
• Family history: If kidney disease is prevalent in your family, you may be more prone to experiencing blood in your urine.
• Medications: Certain drugs, including pain relievers, blood thinners, and some antibiotics, can elevate the risk of haematuria.
• Physical activity: Intense exercise, particularly contact sports or long-distance running (sometimes referred to as "marathon runner’s haematuria"), can increase the risk of developing this condition.

What Should You Do if You Urine Blood?: Diagnosis and Treatment of Haematuria

If you notice blood in your urine, it's essential not to ignore it. Microscopic amounts might be discovered during routine health screenings, even if not visible to the naked eye. Immediate medical consultation is crucial, particularly if you experience symptoms like pain during urination, unexplained weight loss, or urgency.

Serious symptoms requiring urgent care include:

• Fever
• Nausea
• Vomiting
• Chills
• Severe pain
• Inability to urinate
• Passing blood clots

At your medical visit, expect a thorough physical examination. Your healthcare provider may ask you about the onset and nature of symptoms, check for odours or colour changes in your urine, and inquire about any recent foods that could affect urine colour, like beets or berries. They might also ask about any recent medical history that could influence your symptoms.

Diagnostic tests may include:

• Urinalysis: To check for substances in the urine.
• Urine Culture: To identify any infections.
• Urine Cytology: Check for abnormal cells in the urine.
• Cystoscopy: A procedure using a cystoscope to examine the bladder and urethra.
• Ultrasound: To examine the kidneys and urinary tract.
• CT Scan and MRI: These imaging tests provide pictures of the internal structures and are helpful in diagnosing the cause of haematuria.

Treatment for haematuria will differ based on the underlying cause determined through these diagnostic approaches.

Kidney Cancer

In Singapore, kidney cancer ranks as the seventh most prevalent cancer among males, according to the Singapore Cancer Registry Annual Report 2021. This disease may present symptoms such as blood in the urine, persistent side pain below the ribs, or noticeable swelling in the kidney area.

Early consultation with a general practitioner is crucial for those experiencing these signs, as they can facilitate referrals to cancer specialists for further assessment.

Types of Kidney Cancer

The kidneys can be affected by various cancer types, with renal cell carcinoma (RCC) being the predominant form. Other less common types include transitional cell cancer and Wilms' tumour, which represents a rare paediatric kidney cancer, highlighting the diversity of this disease's manifestations.

Symptoms of Kidney Cancer

There are some signs that may mean you have kidney cancer. Aside from blood in your urine, these include a pain in your side or back that doesn't go away, feeling tired all the time, losing weight without trying, a fever, and swelling in your ankles or legs. If you identify with having these symptoms along with blood in your urine, you should see a doctor right away to be tested for kidney cancer. The earlier the cancer is found, the better the chance of curing it.

How is Kidney Cancer Diagnosed?

Diagnosing kidney cancer involves a combination of blood and urine tests, which can help detect abnormalities such as the presence of red blood cells, bacteria, or cancer cells. These initial screenings provide crucial insights into what might be causing the symptoms.

• Imaging Tests: Imaging techniques play a pivotal role in identifying the location and size of kidney tumours. Common methods include ultrasound, computed tomography (CT) scans, and magnetic resonance imaging (MRI), which offer views of the kidney and surrounding tissues.

• Biopsy: A biopsy may also be necessary. During this procedure, a needle is used to extract a small tissue sample from the kidney or adjacent areas, such as the lymph nodes, for laboratory analysis. However, if the imaging results are conclusive, a biopsy might not be required.

• Staging: Once kidney cancer is confirmed, staging tests are conducted to determine the extent of the disease. This staging helps tailor the treatment plan to the patient's specific condition. Kidney cancer stages range from 1 to 4, with stage 1 indicating a tumour confined to the kidney and stage 4 signifying advanced disease that has spread beyond the kidney or to other parts of the body.

Treating Kidney Cancer

Treatment for kidney cancer often starts with surgical intervention aimed primarily at removing the tumour. This approach varies based on the cancer's stage and location. For localised kidney cancers, surgery might be the sole treatment required, while advanced stages could necessitate additional therapies.

1. Surgical Approaches:
   • Nephrectomy (Complete and Partial):
     1. Complete Nephrectomy: This involves the removal of the entire kidney along with a margin of healthy tissue and possibly nearby lymph nodes or other structures.
     2. Partial Nephrectomy: Also known as kidney-sparing surgery, this procedure targets the removal of the cancerous part of the kidney only, helping preserve as much kidney function as possible. It’s particularly beneficial for patients with a single kidney or small localised tumours.
2. Non-Surgical Treatments:
   • Cryoablation and Radiofrequency Ablation: These methods, ideal for treating small kidney tumours, use extreme cold or high-frequency radio waves to target cancer cells. They are often used when surgery is too risky.
   • Radiation Therapy: While not a primary treatment for kidney cancer due to its resistance, radiation is used to address symptoms in metastatic cases.
   • Targeted Therapy and Immunotherapy: These treatments focus on specific pathways or immune responses to help the body fight the cancer. Immunotherapy boosts the immune system's ability to detect and target cancer cells, whereas targeted therapy impedes the proliferation and spread of cancer by targeting specific molecular pathways involved in tumour development and progression.
3. Other Options:
   • Chemotherapy: Typically, kidney cancer is resistant to chemotherapy; however, it might be employed in rare kidney cancer types where other treatments have failed.

Preventing Kidney Cancer

While it's not entirely possible to prevent kidney cancer due to unknown causes, adopting a healthy lifestyle can significantly reduce your risk. Engaging in regular physical activity and maintaining a healthy diet are crucial steps in preventing not only kidney cancer but also other types of chronic diseases.

Visit A Cancer Doctor In Singapore Today 

With 4.2% of men suffering from kidney cancer and the rising prevalence of this disease at approximately 2-3%, it is best to consider visiting a cancer doctor in Singapore if you are experiencing blood in your urine on a regular basis. And while kidney cancer is often thought of as a men's disease, it's important to note that women are also at risk. In fact, kidney cancer is one of the top 10 cancers in women aged 40-49 and 50-59, according to the Singapore Cancer Registry Annual Report 2021. So, if you're a woman experiencing blood in your urine, don't dismiss it either.

Our team of oncology specialists is dedicated to providing comprehensive and personalised care for each of our patients. At our integrated facility, you can have access to cancer screening and treatment options according to your individual preferences and needs. Make an appointment at one of our clinics today.

“Expert knowledge means better care for cancer”

Written by:

Dr Tay Miah Hiang

MBBS (Singapore)

Med (Singapore)

MRCP (United Kingdom)

FAMS (Medical Oncology)