Can hematuria be real or fake? Here's how to tell the difference!

Many people think that red urine means hematuria, but this is not the case. Hematuria refers to the presence of blood in urine, which can usually be divided into true hematuria and false hematuria. True hematuria is caused by problems inside the urinary system, which leads to the presence of blood in the urine, while false hematuria is caused by factors outside the urine, such as women who are menstruating.

How to distinguish true hematuria from false hematuria?

First of all, true hematuria refers to the red blood cell count in urine exceeding the normal level. The commonly used standards are as follows:

(1) Centrifuged urine

Centrifuge 10 ml of fresh midstream urine for 5 minutes, discard the supernatant, keep 0.5 ml and mix well, take a drop and place it on a slide, observe under a high-power microscope, and the red blood cells should be >3/high-power field of view.

(2) Urine sediment

Red blood cell count>25/μL (different centers may have different judgment criteria due to different detection methods).

(3) Urine Addis count

Red blood cells> 500,000/12 hours.

It should be noted that the urine should be tested within 60 minutes after discharge to avoid dissolution of formed elements and bacterial contamination, which may affect the result. If the urine of patients with true hematuria is left for too long, the red blood cells in the urine may be destroyed and dissolved, and the test results may appear as false hematuria.

Secondly, patients with true hematuria may experience the following symptoms:

0 1: Pain or discomfort If you feel pain or discomfort when urinating, this may be caused by a urinary system problem, such as stones. In this case, the hematuria is usually true hematuria.

0 2: Urine color The urine color of true hematuria is usually dark red, pink or brown, which is caused by blood mixed in the urine.

0 3: Continuous and frequent urination accompanied by hematuria may be a sign of true hematuria.

04: Other symptoms True hematuria is usually accompanied by symptoms of other urinary system problems, such as frequent urination, urgency, painful urination, etc.

So, in what cases may it be pseudohematuria?

01: Menstruating women may experience pseudohematuria during their period because menstrual blood comes into contact with urine and turns it red, which is usually a normal physiological phenomenon.

02: Damage to the skin of the urethral opening. Damage to the skin of the urethral opening may cause a small amount of blood to mix with the urine, causing pseudohematuria.

03: Food or drugs Intake of certain foods or drugs, such as large amounts of food dyes, honey, amaranth, red pitaya, beetroot, blackberries, etc., can cause red urine; rifampicin can cause orange urine; deferoxamine can cause reddish-brown urine; antimalarial drugs (quinidine, etc.), vitamin B complex, carotene, nitrofurantoin, metronidazole, sulfonamides, etc. can cause brown urine; phenytoin sodium can cause pink urine. All of the above can make urine look like hematuria.

04: Not accompanied by other symptoms . Pseudohematuria is usually not accompanied by symptoms related to the urinary system, such as urinary tract infection and low back pain.