Did you know that about ¼ of our blood supply enters the kidney per minute for filtration and about 150-180 liters of blood per day is filtered through the glomerulus. Of the filtered, about 90% is reclaimed. According to the body’s needs, essential nutrients are reabsorbed, and the wastes are secreted from the tubules to be voided as urine. Urine is temporarily stored in the bladder and then moves into through the urethra where it is voided. Urine is sterile when it is formed but can trap microorganisms when it is being released from the urethra. Urine can give a general health condition to an individual. It is one of the three major in Vitro diagnostic screening tests after chemistry profiles and Complete Blood Count (CBC). Urine not only helps the body with the removal of nitrogenous substances and other wastes but is also used for flushing out bacteria.
Urinary tract infection includes urethritis (infection of the urethra), cystitis (infection of the bladder) and pyelonephritis (infection of kidney). It can be seen in all people but predominantly in women due to the anatomy that is the urethra is short in comparison with men. The microorganism can have easy access to the bladder. The main cause is a bacterial infection (Escherichia coli). Others like sexual intercourse having more partners, kidney stones, diabetes, for women using a contraceptive diaphragm, using spermicide, menopause, too tight and nonbreathable underwear, and using douche are causative agents.
E. coli is a normal flora of the intestine. It is introduced to the vaginal area through improper wiping of bowel movement (instead of from front to back, from back to front) and gets access to the urethra then to the bladder which results in urethritis and cystitis respectively. If left untreated it can infect the kidney (pyelonephritis) and make the treatment complicated.
In a diabetic patient, if their blood is uncontrolled their urine has glucose. The glucose can aggravate the growth of bacteria and affect the normal flora of the external orifice that helps in prevention. In menopause, the estrogen level is decreased that makes the urinary tract prone to infection. Sexual activity affects urinary tract infections and also increases by having more partners. Aged people are also affected by cystitis because their bladder is not emptied full, this is maybe due to prostate or other causes.
Signs and Symptoms
Frequent and urgent need to urinate, dysuria (pain during urination), back pain and flank pain, abdominal discomfort, fever, and nausea. The color and turbidity may change and also the smell may be foul or stingy due to bacteria growth.
First-morning midstream urine (first void to the toilet so that to flush any bacteria available in the urethra) is good for general urine tests especially for bacterial infection screening tests using the random urinalysis method because urine must be at least 4 to 6 hours incubated in the bladder so that if bacteria (E. coli) is available to see the conversion of the nitrate (normal in urine) to nitrite. But should be confirmed by culture, that is collected in a clean-catch midstream method.
Prevention and Management
A proper way of bowel movement (wiping from front to back), drinking plenty of water is one of the ways to dilute our urine and have frequent urination which is very helpful in flushing out bacteria. Changing urination habits is good. When our reflex sends the signal for the void, an immediate response is good. After intercourse voiding and washing are also advisable. Avoid spermicidal and douche (it can disrupt the normal flora). Personal hygiene is important in the prevention of bacterial growth. A common treatment is antibiotics, usually prescribed by a doctor.
Written By: Emmanuel Tesfamichael
1, Linne and Ringsruds Clinical Laboratory Science: Concepts, Procedures, and Clinical Applications, Mary Louise Turgeon, 7th edition, Jan. 2019, an imprint of Elsevier Inc.
2, Elaine N Marieb: Suzanne M. Keller, Essential of Human Anatomy and Physiology, 12th Edition.