Understanding the complexity
What is Hematuria?
Hematuria, put simply, is the presence of blood in the urine. But what exactly does that mean? Let’s break it down. “Hema-” is derived from the ancient Greek word for blood, and “-uria” is a common medical suffix referring to urine. So, hematuria literally means “blood in the urine.”

But before you hit the panic button, take a deep breath. While the sight of blood in your urine can indeed be alarming, it doesn’t necessarily indicate a severe health condition. Blood in the urine is a red flag (no pun intended) that your body is trying to draw attention to something in your urinary system. This could be anything from an infection to kidney disease or, in rare cases, even cancer.
When it comes to blood in urine context is key. It’s important to remember that a single instance of this could be due to a variety of reasons, some less concerning than others. For instance, dehydration, vigorous exercise, or certain medications can cause temporary hematuria—however, persistent or recurrent hematuria warrants medical evaluation to identify and address the underlying cause appropriately.
Types: Gross and Microscopic
1. Gross Hematuria:
Gross hematuria describes a condition where the presence of blood in the urine is visible to the naked eye. Here are some key points about gross hematuria:
- Visible Blood: The distinguishing factor of gross hematuria is that the blood in the urine can be clearly seen. The amount of blood is significant enough to change the color of the urine.
- Color Change: The color of urine in gross hematuria may range from pink to bright red or even dark brown, similar to the color of cola. The change in color depends on the amount of blood present and how long it has been in the urinary tract.
- Doesn’t Indicate Severity: It’s essential to understand that the visibility of blood does not necessarily imply a severe condition. Gross hematuria could be the result of minor issues such as urinary tract infections (UTIs) or more serious conditions like kidney stones, bladder infections, or in rare cases, tumors.
2. Microscopic Hematuria:
Microscopic hematuria, on the other hand, refers to the condition where red blood cells are present in the urine but in such small quantities that they can’t be seen without a microscope. Let’s explore some key details:
- Invisible Blood: Microscopic hematuria means the blood in the urine is not visible to the naked eye. The blood cells are only detectable under a microscope.
- Detection: This type of hematuria is often detected during a routine urinalysis, a standard urine test. If there are three or more red blood cells per high power field in your urine sample under a microscope, it is categorized as microscopic hematuria.
- Indication: Just like gross hematuria, the microscopic form doesn’t necessarily signal a severe health problem. It can be due to rigorous exercises, medications, benign prostatic hyperplasia (BPH), and severe conditions like kidney disease or bladder cancer.
Interestingly, the distinction between gross and microscopic hematuria doesn’t indicate the underlying cause’s severity. You could have gross hematuria due to a simple urinary tract infection or microscopic hematuria as a symptom of kidney disease. The critical aspect is not to ignore the symptom but to get it checked out by a healthcare professional.
The Underlying Causes of Hematuria
It may arise from a wide array of conditions. While some are relatively harmless, others may indicate serious health problems.

- Urinary Tract Infections (UTIs): UTIs occur when bacteria invade the urinary system, including the bladder and urethra. It’s common to see hematuria in such cases as the infection may irritate the urethra or the lining of the bladder, leading to bleeding.
- Kidney Infections: Similar to UTIs, kidney infections are typically bacterial and can cause bleeding into the urinary system, resulting in hematuria.
- Bladder or Kidney Stones: These form from the crystallization of the minerals in the concentrated urine. If these stones cause enough irritation to the bladder or kidney lining or cause a blockage, there might be blood in the urine.
- Kidney Disease: Various kidney diseases, such as glomerulonephritis, can lead to blood in the urine. They can cause inflammation in the kidney’s filtering system, leading to the leakage of red blood cells into the urine.
- Cancer: Hematuria can sometimes be a sign of cancers like bladder, kidney, or prostate cancer. In these cases, the blood in the urine often appears late in the disease.
- Medications: Certain drugs like aspirin, antibiotics, anticoagulants, and nonsteroidal anti-inflammatory drugs (NSAIDs) may cause hematuria.
- Strenuous Exercise: Intense physical activities like long-distance running can cause bladder trauma, leading to temporary hematuria. This condition is often called “jogger’s hematuria.”
- Injury: Kidneys or urinary tract trauma can cause blood in the urine.
- Prostate Infection or Inflammation: Prostatitis, an inflammation or infection in the prostate, can cause blood in the urine.
- Cystitis: This is an inflammation of the bladder, often caused by an infection or irritation. Cystitis can lead to hematuria.
- Polycystic Kidney Disease: This is a genetic disorder characterized by the growth of numerous cysts in the kidneys. It can cause hematuria.
- IgA Nephropathy: This kidney disease results from an accumulation of the antibody immunoglobulin A (IgA) inside the filters (glomeruli) within the kidneys. It can cause hematuria.
- Sickle Cell Anemia is a genetic condition where the red blood cells become sickle-shaped, leading to various problems, including hematuria.
- Hemophilia: Hemophilia is a bleeding disorder where the blood doesn’t clot normally, which can lead to hematuria.
- Lupus: Lupus is an autoimmune disease that can cause inflammation of the kidneys, which can result in hematuria.
- Schistosomiasis: This is a type of infection caused by parasitic worms. If the urinary tract gets infected, it can lead to hematuria.
- Alport Syndrome is a genetic condition characterized by kidney disease, hearing loss, and eye abnormalities. It can cause hematuria.
- Thin Basement Membrane Disease: This hereditary condition can cause blood in the urine.
- Endometriosis: In rare cases, endometriosis tissue can attach to the bladder, leading to periodic hematuria.
- Sexual Activity: In some cases, sexual activity can cause mechanical trauma to the urinary system, leading to transient hematuria.
It is crucial to understand that the presence of blood in the urine is not a disease in itself but a symptom of an underlying condition, and therefore, it’s essential to consult a healthcare professional for proper diagnosis and treatment.
References:
- Hematuria: Mayo Clinic
- Hematuria: MedlinePlus
- Hematuria: National Institute of Diabetes and Digestive and Kidney Diseases
- Hematuria: American Kidney Fund
- Hematuria: Cleveland Clinic
My other Posts:
- Gross Anatomy of the Kidney: An In-Depth Exploration of Kidney Structure
- Does Blood Transfusion Increase Creatinine?
- Recognizing the Signs and Symptoms of Chronic Kidney Disease
- Chronic Kidney Disease (CKD) And the Causes
- The Stages of Chronic Kidney Disease
Disclaimer: The information provided in this article is for educational and informational purposes only. It should not be used as a replacement for professional medical advice, diagnosis, or treatment. The reader should always consult with a healthcare professional for any health-related concerns, including but not limited to medical conditions and health advice. The use of any information from this article is solely at the reader’s discretion. While every effort has been made to ensure the accuracy of the information, we do not guarantee the completeness, timeliness, or accuracy of the details presented.