🚽 Urinary Tract Infection (UTI): Symptoms, Causes & Treatment

Urinary tract infections (UTIs) are among the most common bacterial infections, affecting millions of people each year — especially women. A UTI occurs when bacteria enter the urinary system through the urethra and begin to multiply in the bladder. While a mild bladder infection (cystitis) is uncomfortable, if the bacteria travel upward into the kidneys (pyelonephritis), it becomes a serious systemic illness requiring urgent medical care. Dr. Ravi Sishir Reddy explains the symptoms, causes, and treatment of UTIs, and how to reduce your risk of recurrence.

1. What Is a Urinary Tract Infection?

The urinary tract consists of the kidneys (which filter blood to produce urine), the ureters (tubes that carry urine from the kidneys to the bladder), the bladder (which stores urine), and the urethra (the tube that carries urine out of the body). A UTI most often begins in the lower tract — the urethra and bladder — and is caused by bacteria, most commonly Escherichia coli (E. coli), which normally lives in the large intestine. When E. coli is transferred from the anal area to the urethral opening — often during sexual activity, wiping back to front, or poor hygiene — it can ascend into the bladder and cause an infection. If the infection is not treated, it can continue upward to the kidneys.

UTIs are far more common in women than in men because the female urethra is much shorter, providing a shorter path for bacteria to reach the bladder. About 50‑60% of women will experience at least one UTI in their lifetime, and many will have recurrent infections. In men, UTIs are less frequent and are often associated with an enlarged prostate or other structural abnormalities.

2. Symptoms of a UTI

Symptoms vary depending on which part of the urinary tract is infected:

Lower UTI (Cystitis / Urethritis):

• Dysuria: A sharp, burning pain or stinging sensation when passing urine. This is the hallmark symptom.
• Increased frequency: A constant urge to urinate, even when the bladder is almost empty.
• Urgency: A sudden, compelling need to urinate immediately.
• Passing only small amounts of urine each time.
• Cloudy, dark, or foul‑smelling urine.
• Blood in the urine (haematuria) — the urine may appear pink, red, or cola‑coloured.
• Lower abdominal or pelvic discomfort — a feeling of pressure above the pubic bone.

Upper UTI (Pyelonephritis – Kidney Infection):

When the infection ascends to the kidneys, it becomes a more serious systemic illness. Symptoms include:

• High fever (often above 101°F / 38.3°C) with shaking chills and rigors.
• Flank pain — pain in the upper back or side, just below the ribs, usually on one side. It may be severe and constant.
• Nausea and vomiting.
• Generalised fatigue, weakness, and feeling very unwell.
• Some patients may still have the lower UTI symptoms (burning, frequency) as well.

Pyelonephritis requires prompt medical evaluation and antibiotic treatment. If left untreated, it can lead to sepsis, kidney abscesses, and permanent scarring of the kidneys.

3. How Is a UTI Diagnosed?

Diagnosis is based on symptoms and a simple urine test:

• Urine dipstick test: A rapid test done in the clinic that checks for nitrites (produced by bacteria) and leukocyte esterase (an enzyme from white blood cells). A positive result strongly supports a UTI, but it is not always conclusive.
• Urine microscopy and culture: The gold standard. A mid‑stream urine sample (collected after cleaning the genital area) is sent to the lab. A urine culture identifies the specific bacteria causing the infection and tests which antibiotics will work against it (sensitivity). Results take 2‑3 days, but treatment is usually started empirically based on symptoms and the dipstick result.
• Imaging (ultrasound or CT scan): Usually reserved for patients with recurrent infections, suspected kidney stones, or pyelonephritis that does not respond to treatment, to check for anatomical abnormalities or obstructions.

4. Treatment: Antibiotics and Symptom Relief

UTIs are bacterial infections and require antibiotics to clear. The choice of antibiotic and duration of treatment depend on the severity and location of the infection:

• Uncomplicated lower UTI (cystitis) in women: A short course of oral antibiotics — typically nitrofurantoin (100 mg twice daily for 5 days), fosfomycin (a single 3‑g sachet dissolved in water), or trimethoprim‑sulfamethoxazole (for 3 days) — depending on local resistance patterns and allergies. Symptoms usually improve within 1‑2 days of starting antibiotics, but it is essential to complete the full course to ensure all bacteria are eradicated.
• UTI in men, recurrent UTIs, or pyelonephritis: A longer course of antibiotics (7‑14 days) is needed. Pyelonephritis often requires intravenous antibiotics (such as ceftriaxone) and hospitalisation, especially if the patient is vomiting, has high fever, or shows signs of sepsis.
• Phenazopyridine (Pyridium): A urinary analgesic that can be prescribed for 1‑2 days to relieve the severe burning and urgency while the antibiotic takes effect. It turns the urine bright orange‑red — this is harmless. It is not an antibiotic and does not treat the infection.

Dr. Reddy emphasises that cranberry juice or cranberry supplements may have a modest effect in preventing UTIs in some women, but they are not effective for treating an active infection. Do not rely on cranberry products to cure a UTI — you need antibiotics.

5. How to Prevent UTIs (Especially Recurrent Infections)

• Stay well hydrated: Drinking plenty of water dilutes the urine and ensures you urinate frequently, flushing bacteria out of the bladder before they can establish an infection.
• Wipe from front to back: After using the toilet, always wipe from front to back to prevent bacteria from the anal area from being moved toward the urethra.
• Urinate soon after sexual intercourse: This helps flush out any bacteria that may have been introduced into the urethra during sex.
• Avoid potentially irritating feminine products: Douches, deodorant sprays, scented powders, and bubble baths can irritate the urethra and increase infection risk.
• Consider vaginal estrogen (for postmenopausal women): The decline in estrogen after menopause thins and dries the vaginal and urethral tissues, making them more vulnerable to infection. Topical vaginal estrogen prescribed by a doctor can restore the natural protective barrier and significantly reduce recurrent UTIs.
• Low‑dose prophylactic antibiotics: For women who experience very frequent UTIs (three or more per year), a doctor may prescribe a low‑dose antibiotic taken daily or after sexual intercourse to prevent infections. This is a decision made after weighing the benefits against the risk of antibiotic resistance.