Urinary tract infection

What is a urinary tract infection (UTI)?

Infections can occur anywhere along the urinary tract, from the kidneys to the ureters (the tubes that drain urine out of the kidneys into the bladder), the bladder or the urethra (the tube leading out of the bladder).

Urinary tract infections are almost always caused by bacteria, especially E.coli, which is normally found on the skin around the bottom and comes from the bowels.

A urinary tract infection is normally described as either upper or lower. An upper UTI or pyelonephritis is an infection in the kidneys. A lower UTI or cystitis is an infection in the bladder.

In up to 40 per cent of cases, there is some form of structural abnormality that predisposes the person to infection. One of the most common is a condition called vesicoureteric reflux (VUR), which affects the way the ureters join the bladder, allowing urine to flow back up towards the kidney.

Other predisposing factors include not going to the toilet often enough , hurrying in the toilet and not emptying the bladder fully (all may mean that any bugs in the bladder are not flushed out before they multiply), constipation, inflammation of the vulva (girls) or damage to the bladder nerves.

Symptoms

In older children, typical symptoms include fever, shivers, pain passing urine, the sensation of needing to pass urine frequently, blood in the urine, pain in the abdomen or loins, vomiting and diarrhoea.

In younger children and babies, there may not be any specific symptoms, simply a feverish, irritable or drowsy child who's off her feeds, vomiting or has diarrhoea.

Causes and risk factors

It is difficult to know exactly how many children get UTIs. Recent figures have suggested that as many as 1 in 10 girls and 1 in 30 boys will have a UTI by the time they are 16. Girls are more vulnerable because the urethra is much shorter than in boys and bacteria can pass easily into the urinary tract.

Infection is confirmed by examining a sample of urine in the laboratory for bacteria. Your doctor can show you how to take a urine sample from your child.

Treatment and recovery

Treatment is with antibiotics and plenty of fluids to flush through the urinary system. In severe cases, or with small babies, hospital treatment may be necessary.

In order to prevent children from getting UTIs, they should be encouraged to drink water regularly, constipation should be treated and girls should be taught to wipe from front to back after going to the toilet (in order to prevent the bugs around their anus from spreading forwards).

The majority of children who have a simple UTI will suffer no sequelae. Children who have repeated UTIs or unusual UTIs will need further investigations to look for abnormalities such as VUR. Children who have VUR may develop scars on their kidneys which may lead to problems later in life (for example, high blood pressure).