If you see visible blood in your urine, get checked once, even if it doesn't hurt and even if it's gone by the next day

Cost

A urinalysis costs a few dozen CNY and a urinary tract ultrasound one or two hundred. If the doctor thinks it's needed, a cystoscopy adds about a thousand CNY.

What you get

A study in the U.K. used electronic records from community general practice (primary care), with 4915 bladder cancer cases against 21718 controls. Among people who had visible blood in the urine, the share in whom bladder cancer was eventually found was 2.8% for those over 60 (95% CI 2.5 to 3.1, the plausible range) and 1.2% for ages 40 to 59 (95% CI 0.6 to 2.3). This share is technically called the positive predictive value. Blood that can be seen only under a microscope is also meaningful. The odds ratio was 20 (95% CI 12 to 33). For people over 60 this share was 1.6% (95% CI 1.2 to 2.1). The U.K. National Health Service (NHS) says blood in the urine can be a sign of cancer and must be checked. Even with no other symptoms, even if it is the first time and the amount is small, make an appointment with a doctor as soon as possible

Notes

“It doesn't hurt” is not a reason to let it go. The U.K. National Health Service (NHS) states that if there is blood in the urine, you should make an appointment with a doctor as soon as possible, even with no other symptoms, even if it is the first time or the amount is small, or if you aren't sure it is blood. Pain when urinating, frequent urination and fever may be a urinary tract infection. Sudden bouts of severe pain from the side of the back to the groin, with restlessness, may be a kidney stone. But the NHS also says not to reach your own conclusion; let a doctor look. Red you see during a period, after eating beetroot, or after starting a new medicine does not necessarily mean the urine has blood in it. If you are taking blood thinners, don't decide on your own that the medicine caused it either; this is the author's advice, and the study above did not count this group separately. The benefit is rated “small” because there is only a detection rate and no effect size for how much earlier checking lowers deaths.

Evidence grade

B : Supported by research but without a precise number, or based on small or single studies.

Sources

1. Price SJ, Shephard EA, Stapley SA, Barraclough K, Hamilton WT (2014). Non-visible versus visible haematuria and bladder cancer risk: a study of electronic records in primary care. British Journal of General Practice, 64(626), e584-e589. https://doi.org/10.3399/bjgp14X681409
2. NHS. Blood in urine: "Blood in your pee must be checked out because it can be a sign of cancer." "But do not self-diagnose." "It may not be blood in your pee if: you've recently eaten beetroot ... you're taking a new medicine ... it's happening during your period". https://www.nhs.uk/symptoms/blood-in-urine/
3. NHS. Symptoms of bladder cancer: "You have blood in your pee, even if: you do not have any other symptoms; it's the first time it's happened; there's only a small amount of blood; you're not sure if it's blood". https://www.nhs.uk/conditions/bladder-cancer/symptoms/

Translated from the Chinese original. Original book, section 1, tip 27. This section is about health and medicines. It is general information, not a substitute for a doctor’s diagnosis or prescription. Content may be out of date and rules differ by place. When you actually deal with an agency, a doctor or a court, follow what local officials, doctors and lawyers tell you. Disclaimer