You can have a kidney infection (pyelonephritis) without knowing for a short time if symptoms are mild (like slight urinary changes), but it often presents quickly with strong signs like fever, chills, back/side pain, nausea, and feeling generally unwell, developing over hours or a day, and it should prompt immediate medical attention as it can worsen fast and lead to serious issues like sepsis if untreated.
Nerve or spinal cord damage can block the feeling of a bladder infection. That can make it hard to know when an infection travels to a kidney.
About kidney infections
It's more serious than cystitis, a common infection of the bladder that makes urinating painful. If treated promptly, a kidney infection doesn't cause serious harm, but will make you feel very unwell. If a kidney infection isn't treated, it can get worse and cause permanent kidney damage.
What Are the Symptoms of an Acute Kidney Infection? Signs and symptoms vary with age: Newborns: no fever but poor feeding and vomiting. Children <2: may have a fever (but not always), a poor appetite, vomiting and diarrhea.
Kidney stones can be tricky, since they may have many of the same symptoms as a UTI or a kidney infection – pain when urinating, needing to urinate often, and cloudy or strong smelling urine, blood in the urine, fever, nausea or vomiting.
Symptoms of a kidney infection can include:
Key facts. Kidney pain is usually felt in your back or side and may spread to your groin. It can be caused by kidney stones, kidney infection or other kidney or urinary tract problems. The cause of kidney pain can be diagnosed with blood tests, urine tests and an x-ray, ultrasound or CT scan.
Recognising the symptoms of sepsis
Symptoms can include:
Kidney disease can affect different parts of your body, including your digestive tract. Even though constipation (not passing stools regularly) is usually the most common digestive problem associated with kidney disease, diarrhea is also common for many people living with kidney disease.
Hospitalization for severe kidney infections
If your kidney infection is severe, you may need to go to the hospital. Treatment might include antibiotics and fluids through a vein in your arm.
In mild cases, you might deal with discomfort for about a week or two, but this depends on your immune system's ability to fight off the infection. In other situations, untreated infections can persist for weeks, spreading to the kidneys and causing more severe health issues like pyelonephritis.
Can a kidney infection go away by itself? For some people, lower UTIs can go away on their own, but kidney infections can lead to serious complications if left untreated. Talk to a healthcare provider if you have symptoms of a kidney infection.
On average, it can take between a few days to a week for a UTI to turn into a kidney infection if left untreated. However, this timeline can vary depending on individual factors such as your general health, age, and the bacteria causing the infection.
Asymptomatic bacteriuria is when you have bacteria in your urine but don't have symptoms of a urinary tract infection. It's very common and doesn't need to be treated most of the time. Pregnant women, kidney transplant recipients and people who are having certain procedures may be treated with antibiotics.
Criteria for hospitalization: can be treated as an outpatient if the patient is stable. If the below factors are present, consider inpatient treatment. Complications: renal or perinephric abscess, emphysematous pyelonephritis, nephronia (focal bacterial nephritis), renal papillary necrosis.
Nausea and vomiting, muscle cramps, loss of appetite, swelling via feet and ankles, dry, itchy skin, shortness of breath, trouble sleeping, urinating either too much or too little. However, these are usually in the later stages, but they can also happen in other disorders.
Where do I feel kidney pain? You feel kidney pain near the middle of your back, just under your ribcage, on each side of your spine where your kidneys are. Your kidneys are part of the urinary tract, the organs that make and remove urine from the body.
A bladder infection usually causes burning, needing to urinate often or cloudy, smelly urine. A kidney infection can include those signs, but often adds more serious symptoms like fever, nausea or back pain.
Symptoms of sepsis
Fast, shallow breathing. Sweating for no clear reason. Feeling lightheaded. Shivering.
Seek immediate medical attention if you experience any of the following symptoms when passing a kidney stone: Severe pain, vomiting, fever and/or chills. Visible blood in the urine. Difficulty urinating.
Medicine to treat kidney infection
Dull or sharp pain in the low back (often confused for kidney pain) is more likely due to a muscle pull, spinal issue, such as sciatica, or an injury. Kidney pain is usually felt higher up in the back and very rarely that low.
You can check kidney function at home using at-home test kits for urine (detecting protein/albumin) or finger-prick blood tests (checking creatinine/eGFR), often with smartphone apps for analysis, or by monitoring symptoms like increased nighttime urination (nocturia), swelling, or changes in urine (blood, foam) and discussing results with a doctor, as home tests screen but don't replace professional diagnosis.
Life expectancy with kidney disease varies widely, from years to decades, depending on the stage, age, overall health, and treatment (like dialysis or transplant), with many people living long lives with early stages, while End-Stage Renal Disease (ESRD) requires dialysis or transplant for survival, with average dialysis patients living 5-10 years but many living much longer.