A<unk>  <unk>  is an<unk>  that affects part of the urinary<unk> . When it affects the lower urinary<unk>  it is known as a bladder<unk>  (cystitis) and when it affects the upper urinary<unk>  it is known as a kidney<unk>  (pyelonephritis). Symptoms from a lower<unk>  include pain with urination, frequent urination, and feeling the need to urinate despite having an empty bladder. Symptoms of a kidney<unk>  include fever and flank pain usually in addition to the symptoms of a lower<unk> . Rarely the urine may appear bloody. In the very old and the very young, symptoms may be vague or non-specific. The most common cause of<unk>  is Escherichia coli, though other bacteria or fungi may sometimes be the cause. Risk factors include female anatomy, sexual intercourse, diabetes, obesity, and family history. Although sexual intercourse is a risk factor,<unk> s are not classified as sexually transmitted<unk> s (STIs). Kidney<unk> , if it occurs, usually follows a bladder<unk>  but may also result from a blood-borne<unk> . Diagnosis in young healthy women can be based on symptoms alone. In those with vague symptoms, diagnosis can be difficult because bacteria may be present without there being an<unk> . In complicated cases or if treatment fails, a urine culture may be useful. In uncomplicated cases,<unk> s are treated with a short course of antibiotics such as nitrofurantoin or trimethoprim/sulfamethoxazole. Resistance to many of the antibiotics used to treat this condition is increasing. In complicated cases, a longer course or intravenous antibiotics may be needed. If symptoms do not improve in two or three days, further diagnostic testing may be needed. Phenazopyridine may help with symptoms. In those who have bacteria or white blood cells in their urine but have no symptoms, antibiotics are generally not needed, although during pregnancy is an exception. In those with frequent<unk> s, a short course of antibiotics may be taken as soon as symptoms begin or long-term antibiotics may be used as a preventive measure. About 150million people develop a<unk>  in a given year. They are more common in women than men. In women, they are the most common form of bacterial<unk> . Up to 10% of women have a<unk>  in a given year, and half of women have at least one<unk>  at some point in their lifetime. They occur most frequently between the ages of 16 and 35years. Recurrences are common.<unk> s have been described since ancient times with the first documented description in the Ebers Papyrus dated to c. 1550 BC. script)
Urinary tract infection
Vaginitis
Ureteral neoplasm
Interstitial cystitis
Pyelonephritis
Pelvic inflammatory disease
Urinary bladder disease
Urethritis