Urinary Tract Infection (UTI) — Diagnosis, Treatment and Prevention

A burning sensation while passing urine is one of the most common complaints I hear in clinic, and more often than not it turns out to be a urinary tract infection. UTI is among the most common bacterial infections worldwide, and while most cases are easy to treat, they are also easy to mismanage.

What is a UTI?

A UTI is an infection of any part of the urinary system: the urethra, bladder, ureters or kidneys. Infection of the bladder is called cystitis, while infection that has traveled up to the kidney is pyelonephritis. Escherichia coli from the gut is the culprit in the majority of uncomplicated cases, roughly 70–95%.

Who is at risk?

Women are affected far more often than men because the urethra is shorter. Up to half of all women will have at least one UTI in their lifetime. Other risk factors include:

• Pregnancy and menopause
• Diabetes and other causes of weak immunity
• Kidney stones or an enlarged prostate causing obstruction
• Urinary catheters
• Frequent sexual activity or use of spermicides
• Poor fluid intake or habitually holding urine

Symptoms

Lower UTI (cystitis) typically causes dysuria, urinary frequency, urgency, lower abdominal discomfort, and cloudy or foul-smelling urine. Sometimes there is blood in the urine.

Pyelonephritis is more serious. Fever with chills, flank pain, nausea and vomiting suggest the kidney is involved, and these patients need prompt medical attention. In young children and the elderly, a UTI may show up only as fever, irritability or confusion.

How is a UTI diagnosed?

Urine R/E

A urine routine examination is the first step. Pus cells (usually more than 5 per high-power field), positive leukocyte esterase and positive nitrite support the diagnosis. Red cells and bacteria may also be seen. A clean-catch midstream sample reduces contamination.

Urine culture

A urine culture identifies the organism and tells us which antibiotics it responds to. It is not always needed for a first, simple cystitis, but I request it in pregnancy, men, suspected pyelonephritis, recurrent infections, diabetic patients, and anyone who has not improved on initial treatment. Ideally, send the sample before starting antibiotics.

Antibiotic treatment

Antibiotics are the mainstay of treatment, and the choice should depend on local resistance patterns, the severity of infection and culture results where available. For uncomplicated cystitis, short courses of nitrofurantoin or a single dose of fosfomycin are commonly recommended first-line options. Fluoroquinolones are best reserved for situations where other options are unsuitable, because of resistance and side effects.

Pyelonephritis usually needs a longer course, and sometimes hospital admission with intravenous antibiotics if the patient is vomiting, dehydrated or systemically unwell. Please complete the full course even if symptoms settle early, and avoid taking leftover antibiotics for the next episode. Asymptomatic bacteriuria generally should not be treated, except in pregnancy or before certain urological procedures.

Preventing recurrence

Recurrent UTI is generally defined as three or more episodes in a year, or two in six months. These simple measures help:

• Drink adequate water through the day
• Do not delay urination, and empty the bladder fully
• Pass urine soon after intercourse
• Wipe front to back and avoid irritating feminine products
• Avoid spermicides
• Keep blood sugar well controlled if you are diabetic
• Ask about vaginal estrogen if you are postmenopausal; it can reduce recurrence

Cranberry products may offer a modest benefit for some people, but they are not a substitute for treatment. If infections keep coming back, your doctor may consider an ultrasound to look for stones or obstruction, or low-dose preventive antibiotics.

See a doctor urgently if you have fever, flank pain, vomiting, blood in the urine, or if you are pregnant or diabetic.