Recognizing the Red Flags
18 Warning Signs of Kidney Infection
Kidney infections — medically known as pyelonephritis — can develop quickly and may lead to serious health complications if not treated early. Because symptoms can sometimes be mistaken for other illnesses, recognizing the warning signs is extremely important.
In this guide, we’ll break down the most common warning signs of a kidney infection, helping you understand when symptoms may signal a problem and when it’s important to seek medical care. Learning these early indicators can help protect kidney health and reduce the risk of long-term complications.
1. Fever
Fever is the result of an inflammatory response, and it’s a natural symptom that accompanies several types of infections, except in mild infections or immunocompromised patients. It is a common symptom in kidney infections, especially in severe cases.
Fever is not always present in kidney infections, and whenever it appears it may be a signal that the disease is progressing. Fever in pyelonephritis may rise up to 40°C or 103°F, but it can be controlled with medications, and usually disappears after a few days of antibiotic treatment.
2. Shivering
It is a common symptom that usually accompanies fever. The body temperature rises because the brain dictates the rest of the body it should do whatever is necessary to increase temperature. Since your set point is higher than your actual temperature, you start feeling cold when your temperature is hot, and the muscles start contracting and relaxing to create additional heat. Shivering in kidney infections can be severe and uncontrollable, especially when the body temperature reaches 40°C or 103°F.
3. Nausea and Vomiting
Because it doesn’t manifest until the infection has spread to the kidneys, it is a fairly recognizable symptom. Sometimes a bladder infection may cause some nausea, but never vomiting. The gastrointestinal system undergoes changes during kidney infections, and patients often experience loss of appetite as well.
4. Diarrhea
As a part of their gastrointestinal symptoms, some patients experience diarrhea as well. While it is not a distinctive feature in kidney infections, it can be encompassed as a part of the disease and does not always require extra studies to find out the cause.
5. Back or Flank Pain
Another distinctive symptom, patients usually report a dull ache in the lumbar area, on the affected flank, and sometimes around the groin. It is more common in the flanks, and the location of the pain usually corresponds to the position of the affected kidney.
6. Pus or Blood in the Urine
Blood and pus in the urine are known as hematuria and pyuria respectively. This data is usually retrieved after taking and analyzing a urine sample, but in some cases, we can see macroscopic blood in the urine without a lab report. Pus in the urine makes it look cloudy, and it is the result of an elevated white blood cell count resulting from the body trying to fight off the kidney infection.
Blood in the urine may also indicate there’s a kidney stone working its way down the urinary tract and scraping the ureters and urethra in the process. When this happens, solving kidney stones becomes a priority along with fighting off the infection because it is considered to be the root cause.
