Urinary tract infection

An infection anywhere in the urinary tract. It has differing symptoms, depending on the area affected. Urethritis causes a burning sensation when urine is being passed. Cystitis causes a frequent urge to pass urine, lower abdominal pain, haematuria, and, often, general malaise with a mild fever. Pyelonephritis causes fever and pain in the back under the ribs. Cystitis and pyelonephritis are almost always the result of a bacterial infection. Urethritis is often due to a sexually transmitted infection, such as gonorrhoea, but may have other causes. Urethral infections are more common in men. Infections further up the urinary tract are more common in women. In men, there is often a predisposing factor, such as an enlarged prostate gland (see prostate, enlarged). In women, pregnancy is a risk factor. In both sexes, causes of urinary tract infections include stones (see calculus, urinary tract), bladder tumours, congenital abnormalities of the urinary tract, or defective bladder emptying as a result of spina bifida or a spinal injury. The risks of developing a urinary tract infection can be reduced by strict personal hygiene, drinking lots of fluids, and regularly emptying the bladder. Urethritis can lead to the formation of a urethral stricture. Cystitis usually only causes complications if the infection spreads to the kidneys. Pyelonephritis, if it is left untreated, can lead to permanent kidney damage, septicaemia, and septic shock. The infection is diagnosed by the examination of a urine culture. Further investigations using urography or ultrasound scanning may be necessary. Most infections of the urinary tract are treated with antibiotic drugs.