Escherichia coli (E. coli) is the single most common pathogen in both community and hospital-acquired urinary tract infections (UTIs), accounting for 80 to 90 percent of cases, according to "Infectious Diseases of the Female Genital Tract." In contrast to many other microorganisms implicated in UTIs, E. Coli grows quickly and adapts to many different sites in the body. If you have the symptoms of UTI, visit your doctor as soon as possible.
Signs & Symptoms of UTI
The single most common symptom of an E. coli UTI is dysuria, pain or burning upon urination, which results from urine passing through the inflamed, infected urethra. Two other symptoms, urgency and frequency of urination, are signs that the infection has ascended to the bladder. Infection causes the smooth muscle lining the bladder to contract more forcefully and frequently than normal, which you experience as increased urgency and frequency. Together, the presence of these three symptoms generally indicate the presence of a UTI, but a urine culture is needed to determine which bacteria is causing the infection.
Other signs of UTI include blood in the urine, abnormal color, foul odor and cloudy or particulate urine. Small amounts of blood may be seen when irritation produces superficial erosion in the urethra or bladder. Blood may be easily identifiable or it may present as clots or a pinkish tinge. Urine with a greenish cast signals the presence of pus in the urine (pyruria). Urine that is foul smelling and cloudy is evidence of advanced urinary tract infection.
Acuity & Progression
To some extent, the symptoms of UTI are proportionate to the rate of bacterial growth. Unlike other common uropathogens such as chlamydia and mycoplasma, E. coli grows quickly. Patients with E. coli infections typically describe abrupt onset and a rapid increase in symptom severity. UTIs which seem to develop over a few weeks, which first present with penile or urethral discharge, or which present without frequency and urgency are more likely to be related to other organisms.
Bacteria frequently exhibit a preference or “tropism” for specific types of tissue. The strains of E. coli that most typically infect the urinary tract adhere well to the walls of the bladder, allowing them to multiply easily. However, E. coli can also ascend to the kidneys, and bloodstream, causing more serious infections. If you have symptoms of UTI, call your doctor right away or visit an urgent care center.
If you experience fever, chills, back or flank pain, suprapubic pain or nausea and vomiting, go to the emergency room. In rare cases, E. coli urinary tract infections ascend to the kidneys, a condition called pyelonephritis, which may result in permanent kidney damage. The infection can also spread to the rest of your bloodstream and cause a life-threatening condition called gram-negative sepsis. If you’re older, immunosuppressed such as from cancer or HIV or suffer from multiple medical problems, you may be at greater risk of developing pyelonephritis and sepsis.
Because of its ubiquity, many strains of E. coli have become resistant to the most commonly used antibiotics. Call your doctor if your infection doesn't appear to improve after taking a course of antibiotics.