Kidney infection: symptoms, treatment and when to get urgent help

The NHS lists the symptoms of a kidney infection as including a high temperature, feeling or being sick, pain in your lower back or side, diarrhoea, aching muscles and flu-like symptoms, pain, burning or stinging when you pee, needing to pee more often and urgently than usual, and pee that is dark or cloudy. NHS inform says symptoms usually develop quite quickly over a few hours or days, and the temperature may reach 39.5C.

In young children the NHS says symptoms may also include wetting the bed or themselves and being drowsy, and a child under 2 years may only have a high temperature. The symptoms may be similar to those of other UTIs, such as cystitis.

The NHS says to ask for an urgent GP appointment or get help from NHS 111 if you think you or your child may have a kidney infection and you have a very high temperature or feel hot, cold or shivery, a very low temperature below 36C, pain in the lower tummy or in the back just under the ribs, blood in your pee, are feeling or being sick, have not had a pee all day, or are pregnant. It adds that a kidney infection can be serious if not treated because it can cause sepsis.

Call 999 or go to A&E now if you are confused, drowsy or have difficulty speaking. The NHS says not to drive to A&E; ask someone to drive you or call 999 and bring any medicines you take.

See a GP if you or your child have pain, burning or stinging when you pee, need to pee more often and urgently, have dark or cloudy pee, or still have kidney infection symptoms after treatment with antibiotics.

The NHS says that if the GP thinks you have a kidney infection, your pee will be tested to check. The main treatment is antibiotic tablets, which you will usually take for 7 to 14 days. You will usually feel better after about 2 weeks.

Some people are more vulnerable to the effects of an infection. The NHS says if you have a long-term health condition or you are pregnant, you may need to go to hospital to have antibiotics through a drip, which works faster than tablets. In hospital you will have regular blood and urine tests, and most people are well enough to go home after 3 to 7 days.

NHS inform says that in rare cases a kidney infection can cause blood poisoning (sepsis) and a build-up of pus in the kidney called an abscess, and that untreated infection can cause permanent kidney damage.

The NHS says you will usually feel better after about 2 weeks of treatment, and that it can take up to 2 weeks before you feel able to return to work. People who are older or have underlying conditions may take longer to recover. NHS inform says that after taking antibiotics you should feel completely better after about 2 weeks.

The NHS lists things to try while you are having treatment, which can also help prevent it coming back:

• Rest.

• Drink lots of fluids, such as water or squash, taking small sips if you feel sick.

• Take paracetamol to reduce a high temperature and relieve pain.

• Ask your doctor how much fluid you can drink if you have kidney problems.

• Always try to fully empty your bladder when you pee, and do not hold your pee in if you feel the urge.

• Do not take ibuprofen unless advised by a doctor, as it may increase your risk of further kidney problems.

The NHS says a kidney infection is a type of UTI, caused by bacteria in the tube that carries pee out of the body (urethra). It is often caused by cystitis, another type of UTI, but you can have one without having cystitis. You may be more likely to get one if you have a kidney problem such as kidney stones, certain conditions or a weakened immune system.

NHS inform says the bacteria are usually a type called E. coli, which live in the bowel, and that they get in through the urethra and travel up through the bladder to the kidneys. It says kidney infections are relatively rare (about one in every 830 people each year in the UK), can happen at any age but are much more common in women, with women 6 times more likely than men to get one because the female urethra is shorter.

NHS inform says younger children are vulnerable because they may be born with an abnormality of the urinary tract or a condition called vesico-ureteric reflux, and advises contacting your GP immediately if you think your child may have a kidney infection. A child under 2 may only have a high temperature, according to the NHS.

The NHS lists being pregnant among the reasons to ask for an urgent GP appointment or get help from NHS 111 if you think you may have a kidney infection, and says pregnant people may need antibiotics through a drip in hospital.

The NHS says the symptoms of a kidney infection may be similar to those of other UTIs such as cystitis. NHS inform says a kidney infection is more serious than cystitis, a common infection of the bladder that makes urinating painful.

On the NHS you can start with a GP, NHS 111 or an urgent treatment centre, and a pee test usually confirms the diagnosis. If you are very unwell you may be admitted to hospital.

Private GP and urgent care services also test urine and prescribe antibiotics. Because a kidney infection can become serious quickly, the NHS advice to seek urgent help applies whichever route you use.