Why Do I Have Blood in the Urine aka Hematuria?
Why was I referred to see the urologist for blood in my urine?
The medical definition for blood in the urine is called hematuria. When you will go to the doctor’s office, he/she will typically have you give a urine sample. When you come to the office, you will be told to the go to the bathroom and pee in a cup.
What we do is then test the urine with a special indicator strip. This gives us loads of information about the urine but for the purpose of this post, we care about what it tells about blood in the urine.
Usually the readout from the test will try and measure the amount of blood in the urine–none, trace, small, moderate or large amounts. However, this is not the best way to tell if there is blood in the urine. The best way to tell if there is blood in the urine is to evaluate it under the microscope. The reason for this is that the machine readout can frequently be wrong in thinking there is blood when in fact, it really isn’t there.
So make sure to press your urologist about the number of red blood cells in the urine not just whether the test showed blood or not. This is for what we call–MICROSCOPIC HEMATURIA.
The other form of blood in the urine is called gross hematuria. Not gross like ‘eww’. Gross in this context means that you can see the blood when you pee. For urologists we will quantify gross hematuria in terms of drinks–pink lemonade, Hawaiian punch, red wine, or tomato juice.
We will also ask whether or not you are seeing clots, which are kinda like hard jelly clumps in the urine, as well because this will give us a sense of how much bleeding is actually taking place and what management steps need to be taken.
So…is there a difference between microscopic and gross?
Well they are both signs of blood in the urine, however, gross hematuria carries a higher (still low percentage wise) chance that the workup could reveal cancer. So for these patients, I will typically get the workup done sooner overall to make sure that we aren’t delaying a cancer diagnosis.
Ok, I’m not seeing blood in the urine, but my doc sent the referral. That means I have microscopic hematuria. What will the urologist recommend for this?
The first thing the urologist will want to do is to rule out a urinary tract infection, aka UTI, as the source. To test for this, the urine sample will be sent for a urine culture. This is a test where the urine is put on a special plate and then we wait to see if any bugs, or bacteria, grow. If there is a UTI, then you will be given antibiotics first and then after you have been treated, we will repeat the urine testing. If the urine testing now comes back normal, hooray, you’re done.
If there is no concern for a UTI, then you will be recommended a pretty standard workup. The best way to think about this is that we need to see where in the entire urinary tract the blood could be coming from. So we start from the top to the bottom or the kidneys to the urethra.
As a urologist, its best to divide the urinary tract is into an upper and lower section.
The upper urinary tract is the kidneys and ureters. This is evaluated with imaging. Typically, per the current American Urologic Association (AUA) recommendations, this will be evaluated with a CT urogram. This is a CT scan that has a very specific protocol to evaluate blood in the urine. You will first go through the scanner without any x-ray dye (contrast). This is to look mainly for kidney stones as a source of the bleeding.
The radiology technician will place an IV catheter into your arm and then inject IV contrast (dye) and then wait. The purpose of waiting the 8-10 minutes is to allow the kidneys to process the x-ray dye. You will then go through the CT scanner again. This pass through will help to evaluate other kidney/ureter sources of bleeding like a kidney mass, kidney swelling (hydronephrosis), or ureteral mass or narrowing.
The lower urinary tract is the bladder and urethra. Unfortunately, there is no accurate x-ray test to evaluate this. Neither a CT, MRI, ultrasound, or regular x-ray is accurate enough to evaluate the lower urinary tract. As such, you will come back to the office for a procedure called a cystoscopy.
This is a quick, I’m talking a couple minutes, test where the urologist will look into the urethra and bladder with a camera. Sounds awful, but trust me it’s not too too bad. The main purpose of this test is to rule out bladder cancer but also to check for other sources of blood in the urine as well—enlarged prostate, scar tissue in the urethra, bladder stones, etc.
Are there any other tests that need to be performed?
Some patients have a higher risk of cancer than others. Examples of these situations would be for those who have smoked or had radiation treatment in the past.
As such, another test is to send the urine to the lab for a urine cytology.
This is where a pathologist will evaluate the urine and look for cancer cells. The cytology test can have several results:
- Normal: no signs of cancer cells
- Atypia: cells kinda look funny but not very concerning for cancer cells
- Suspicious: something fishy is going on but not quite there to call it cancer cells
- Positive: this is the real deal. There are cells in the urine that have cancer
If a urine cytology is positive, all that means is that there are cancer cells in the urine. What it doesn’t say is where. This is where the CT urogram and cystoscopy will come in play to try and figure out where those cancer cells are coming from.
Thank goodness, nothing bad was found. Now what?
More often than not, the blood in urine workup will be essentially normal or benign. This is a good thing but can sometimes be frustrating because we want an answer.
Usually the microscopic hematuria is reflective of a extra blood vessels as the open of the bladder or for men within the prostate channel. The amount of blood that is in the urine in this setting is miniscule and will not cause you to be anemic (low body blood count) or have symptoms of low blood counts.
For these patients, we will just follow them meaning you will come back to see the urologist or your regular doc in a year. If during follow up, the blood in the urine persists, we may repeat this whole workup again in 3-5 years times depending on the clinical situation. For those that it goes away, then great, we don’t need to follow this anymore nor do we need to repeat imaging and the cystoscopy.
If the workup does reveal something, your urologist will go over whether this is significant or not and if some sort of intervention is needed.
Blood in the urine sounds scary when you are told that you have this, but just have some comfort that the evaluation is really simple and pretty standardized. More often than not, it’s nothing to worry about but definitely is something that you should see the urologist for and get checked out.
If you want to get into the weeds about blood in the urine evaluation even more, then click over here to see what the American Urologic Association guidelines state.
If you want to learn more about other urology conditions, then head over to Urology Buddy.