As you know when you come for your annual gynecologic visit, the receptionist requests that you update your information, sign a confidentiality form, and she checks on your insurance. The nurse then hands you a small plastic cup and asks you to give a urine sample. So there you are in a cramped bathroom trying to aim the stream into what now seems like an impossibly narrow container and thinking: (a) this is humiliating, (b) why is this necessary, I have no problems with my bladder? and possibly (c) I can’t go, so what am I supposed to do now?
A new article in the Journal Obstetrics and Gynecology aptly titled “In the Trenches” emphasizes the importance of checking your urine.
An immediate urine test can be performed with a “dipstick”, a strip of paper that is specially treated to check for white cells (often present if there is an infection) red blood cells or RBC’s (and the rest of this newsletter will deal with this… if blood is present in the urine, the medical term is hematuria), protein (if elevated, a sign of kidney or even systemic disease), glucose (present in urine if blood levels are high), ketones (elevated with kidney problems or dehydration), bilirubin (elevated in liver disease) and pH (acidity).
The journal article dealt specifically with microscopic hematuria in women. “Microscopic” simply means that there is blood (or red blood cells) in urine but the urine doesn’t look bloody to the naked eye or toilet paper…(I realize this is getting a bit gross!) According to the American Urological Association, “significant microscopic hematuria” means there are three or more red blood cells (RBC’s) per high power field (magnified 40 times) on microscopic examination from two to three properly collected urinalysis specimens. To get a proper sample, the first drops of urine should not be included, just the midstream…all the more difficult to get into that cup. If you have your period, recently exercised vigorously, just had sex or vaginal trauma, obviously blood cells in the urine will not count and the test should be repeated another time.
Once a dip stick test is positive for RBC’s …I (or any doctor) will probably send the urine out for a complete urinalysis. The urine is spun down and the sediment is examined for the number of RBC’s, white cells, and/or bacteria. Often we also do a urine culture to rule out infection. (Most women, however, do know when they have a bladder infection…. they have urinary urgency, frequency and burning.)
So why is it so important to detect microscopic hematuria? Before I relate the possible causes and consequences listed in the journal article, I’ll tell the tale of a patient that I saw a few weeks ago. She was menopausal, had no signs of vaginal bleeding or urinary problems, but a routine urine dipstick test was positive for RBC’s. Her urine was sent out for culture (it was negative) and complete urinalysis. The latter confirmed the presence of a significant amount of RBC’s.. I asked her to repeat the test 2 weeks later and once more it showed RBC’s. I then referred her to a urologic specialist for a complete workup.. This ultimately consisted of cystoscopy and a CT scan of her pelvis and kidneys. She was found to have bladder cancer. It was resectable and curable.. This simple urine test probably saved her life.
The two most frequent causes of microscopic hematuria in non-pregnant women (46% of women do have hematuria during their pregnancy) are cystitis (bladder infection) and kidney stones. Additionally, some women seem to shed RBC’s in their urine without any pathology. But the cause that should be ruled out, especially in women over 40, is cancer. Bladder cancer is the 17th most common cancer in women worldwide. In the United States in 2008 there were 17,770 new cases of bladder cancer diagnosed and 4,270 deaths …that means that there were more deaths annually from bladder cancer in women than from cervical cancer! (A personal aside…. many years ago my paternal grandmother died from bladder cancer.)
The risk factors for urologic cancers in women include age over 40, smoking, a history of exposure to chemicals or dyes, a history of gross hematuria (the “gross” here is a medical term and means that urinary blood is visible), analgesic abuse and a history of pelvic radiation. And here is a fact that seems to appear whenever we discuss most cancers: up to 35% of female bladder cancer cases may be attributable to cigarette smoking!
The recommendations put forth in the article state that a complete work up of microscopic hematuria should include an evaluation of the lower urinary tract (the bladder) and upper urinary tract (the ureters and kidneys) in any “high-risk” patient. Once more, you are at risk if you are over 40, have smoked, have had chemical exposure (hair stylists), have a family history of bladder cancer (I guess that’s me) and/or recurrent urologic disease. The work up should include cystoscopy, x-rays with dye and CT scans.
We all know about the need for Pap smears. It turns out that a urine test is just as important. So please don’t bewail that request to pee in a cup.