Urinary tract infections: symptoms, treatment and prevention

A urinary tract infection (UTI) is a common problem that ranges from a mild bladder infection to a serious kidney infection. This article explains the symptoms, causes, treatment and prevention, using information from the NHS and MedlinePlus.

1. Introduction

The NHS explains that UTIs can affect the bladder, which is called cystitis, the urethra, the tube that carries urine out of the body, or the kidneys ^[1]. Antibiotics, medicines that kill bacteria, may be used, but they are not always needed ^[1]. MedlinePlus says that most UTIs start when bacteria enter the urethra and travel to the bladder, and they can spread to the kidneys ^[2].

2. Causes and risk factors

The NHS says UTIs are usually caused by bacteria from the bowel entering the urinary tract through the urethra ^[1]. Women get them more often because the urethra is shorter ^{[1, 2]}. The NHS lists these risk factors ^[1]:

• Pregnancy and menopause
• Wiping from back to front
• Kidney stones or an enlarged prostate
• Using a urinary catheter, a thin tube that drains the bladder
• A weakened immune system, for example from poorly controlled diabetes or chemotherapy
• Using spermicide
• Not drinking enough fluids
• Constipation in children

MedlinePlus adds older age, conditions that affect personal care, incomplete bladder emptying, and recent urinary tract surgery or procedures ^[2].

3. Signs and symptoms

The NHS lists these common symptoms ^[1]:

• Pain or burning when passing urine
• Needing to pass urine more often, more urgently or at night
• Cloudy urine or blood in the urine
• Lower tummy pain, or back pain just under the ribs
• Fever, shivering, or feeling tired and weak

Dark or smelly urine may simply mean you are not drinking enough water, if it is your only symptom ^[1]. In children, signs can include fever, irritability, poor feeding, bedwetting and vomiting. In older or frail people, people with dementia or people with a catheter, confusion, agitation or worse incontinence may be the signs ^[1].

4. Diagnosis and tests

The NHS says a GP may test a urine sample, although this is not always needed ^[1]. MedlinePlus says a urine test called urinalysis can diagnose an infection most of the time, and that a urine culture may be done to identify the bacteria and choose the best antibiotic ^[2]. Blood tests and scans may be used to check for other problems in the urinary system ^[2].

5. Treatment and management

The NHS says a GP may advise self-care and pain relief, prescribe a short course of antibiotics, or suggest waiting 48 hours to see whether symptoms settle by themselves ^[1]. MedlinePlus says most people with a UTI will need an antibiotic, that all of it should be taken even if you feel better, and that drinking plenty of water helps ^[2]. It adds that bladder infection symptoms most often go away within 24 to 48 hours after treatment begins, while a kidney infection can take a week or longer ^[2]. Severe kidney infections may need hospital care with fluids and antibiotics given through a vein ^[2].

Self-care advice from the NHS includes resting, drinking enough fluids to pass pale urine regularly, and limiting bladder irritants such as fruit juice, coffee and alcohol ^[1]. The NHS says cystitis sachets and cranberry drinks have no evidence of easing or treating an infection that has already started ^[1].

Recurrent and chronic infections

The NHS describes recurrent UTIs as two in six months or three in twelve months. A doctor may then suggest a different antibiotic, a preventive antibiotic taken for up to six months, vaginal oestrogen around or after menopause, preventive tablets or a specialist referral ^[1]. Chronic UTIs, where symptoms persist and tests can miss the infection, may need long-term antibiotics and a specialist opinion ^[1]. MedlinePlus says surgery may be needed if the infection is caused by a problem with the structure of the urinary tract ^[2].

6. Prevention and self-care

The NHS suggests these steps ^[1]:

• Wipe from front to back and keep the genital area clean and dry.
• Drink plenty of fluids.
• Wash around the vagina before and after sex and pass urine soon after sex.
• Wear cotton underwear rather than tight underwear.
• Do not hold in urine or rush when passing it.
• Avoid scented soap around the genitals and spermicidal lubricants.
• Change nappies or incontinence pads promptly if they are soiled.
• Do not have lots of alcoholic drinks or sugary food and drinks, as alcohol may irritate the bladder and sugar may encourage bacteria to grow.

The NHS notes that some evidence suggests D-mannose or cranberry products may help prevent recurrent cystitis, but they can be high in sugar, anyone pregnant should ask a doctor first, and cranberry products should be avoided by people taking the blood thinner warfarin ^[1].

7. Special groups

The NHS advises an urgent GP appointment or NHS 111 for children aged 15 or under, adults aged 65 or over, men, people who are pregnant, and people with diabetes, a catheter or a weakened immune system ^[1]. Women and girls aged 16 to 64 who are not pregnant or breastfeeding may be able to get advice and treatment from a pharmacist ^[1].

8. When to see a doctor

Contact a healthcare provider if you have UTI symptoms ^[2]. If the infection spreads to the kidneys, MedlinePlus lists chills and shaking, fever, pain in the side, back or groin, nausea and vomiting, and confusion, which in older people may be the only sign ^[2]. Get prompt advice if symptoms worsen quickly, do not improve within 48 hours, keep coming back, or include lower tummy pain, back pain just under the ribs, blood in the urine, a very high or low temperature, shivering or vomiting, because these can signal a kidney infection that may lead to sepsis, a dangerous reaction to infection ^{[1, 2]}. MedlinePlus says the risk of sepsis is greater in the very young, in very old adults and in people whose bodies cannot fight infections well, and that kidney damage or scarring is also possible ^[2]. The NHS says confusion, drowsiness or difficulty speaking need emergency care and you should not drive yourself ^[1].

In an emergency, call your local emergency number (112 in India, 911 in the United States).

9. Conclusion

UTIs are common and usually start when bacteria enter the urethra. Simple infections can often be managed with early advice, fluids and, when a doctor decides, a course of antibiotics. Knowing the warning signs of a kidney infection and acting quickly protects your health.