Kidney infection
A kidney infection, also known as pyelonephritis, is a bacterial infection affecting one or both kidneys. This condition often arises from an untreated bladder infection or other factors that impede urine flow, such as kidney stones or an enlarged prostate. Individuals with certain risk factors, including women, those with diabetes, and people with urinary tract abnormalities, are more susceptible to these infections. Symptoms can range from abdominal pain and frequent urination to fever and nausea. Diagnosis typically involves urine tests to detect the presence of bacteria and other abnormalities, while imaging tests may be necessary for recurrent infections. Treatment primarily consists of antibiotics, and in severe cases, hospitalization may be required for intravenous medication. Preventive measures include maintaining good hydration, practicing proper hygiene, and timely urination. As research continues to evolve, there is growing interest in understanding the role of diet and the emergence of antibiotic-resistant infections in kidney health.
Kidney infection
- ANATOMY OR SYSTEM AFFECTED: Genitourinary tract, kidneys
- ALSO KNOWN AS: Pyelonephritis
Definition
Kidney infection occurs when a bacterial infection in one or both kidneys occurs. The kidneys remove waste (in the form of urine) from the body. They also balance the water and electrolyte content in the blood by filtering salt and water.
Causes
Kidney infection may be caused by, most commonly, a bladder infection that was not treated or inadequately treated; conditions that slow the flow of urine from the bladder, such as an enlarged prostate or kidney stones; having a cystoscopy done to examine the bladder; surgery of the urinary tract; use of a catheter to drain urine from the bladder; and, rarely, bacteria from another part of the body that has entered the kidneys.
Risk Factors
The factors that increase the chance of developing kidney infection include sexual activity, pregnancy, diabetes, birth disorders of the urinary tract, including vesicoureteral reflux, blockage of the urinary tract, including tumors, an enlarged prostate gland, kidney stones, or a catheter or stent placed in the urinary tract, polycystic kidneys, sickle cell anemia, previous kidney transplants, and a weakened immune system. Also, girls and women are at greater risk for kidney infection.
Symptoms
Symptoms include pain in the abdomen, lower back, side, or groin; frequent urination; urgent urination that produces only a small amount of urine; sensation of a full bladder, even after urination; burning pain with urination; fever and chills; nausea and vomiting; pus and blood in the urine; and loss of appetite.
Screening and Diagnosis
A doctor will ask about symptoms and medical history and perform a physical exam. A kidney infection is diagnosed with urine tests. The urine is examined for bacteria, white blood cells, blood, and other abnormal elements.
If the infection does not go away after treatment or if the person has had several kidney infections, other tests might be ordered to see if there are problems with the kidney, ureters, and bladder. These tests include a kidney ultrasound (a test that uses sound waves to examine the kidney), an abdominal computed tomography (CT) scan (a detailed X-ray picture that identifies abnormalities of fine tissue structure), and a voiding cystourethrography (an X-ray of the urinary bladder and urethra made after injection with a contrast medium).
Treatment and Therapy
Kidney infections are treated with antibiotics. If the infection is not treated correctly or is left untreated, the condition can lead to septicemia (a blood infection that has spread throughout the body), chronic infection, scarring of the kidney, or permanent kidney damage. In some cases, the infected person may need to be hospitalized and receive antibiotics intravenously.
Prevention and Outcomes
Because kidney infection is often a complication of a bladder infection, the chance of getting a bladder infection can be lessened by drinking increased amounts of fluids (about eight to ten 8-ounce glasses per day); this includes drinking cranberry juice, which may help prevent bladder infection, too. Other preventive measures are to practice good hygiene, to urinate when the need arises, and to take showers rather than baths. Women should wipe from the front to the back after using the toilet, should urinate before and after having sex, and should avoid douches and genital deodorant sprays.
Although the medical community understands kidney infections, in the twenty-first century, advances continue to be made in understanding their causes and developing more targeted treatments. Researchers discovered that a majority of kidney immune cells are developed in embryonic stages. This discovery could lead to more targeted treatments for kidney infections. As antibiotics become increasingly widespread, studies have also increased into antibiotic-resistant kidney infections. Finally, research has indicated that diet may play a key role in preventing kidney infections.
Bibliography
Brenner, Barry M., editor. Brenner and Rector’s The Kidney. 8th ed., Philadelphia: Saunders/Elsevier, 2008.
Greenberg, Arthur, et al., editors. Primer on Kidney Diseases. 4th ed., Philadelphia: Saunders/Elsevier, 2005.
"IU School of Medicine Researchers Discover Promising New Way to Prevent, Treat Kidney Infections." Indiana University School of Medicine, 28 June 2021, medicine.iu.edu/news/2021/06/iu-researchers-discover-promising-new-way-to-prevent-and-treat-kidney-infections. Accessed 25 Sept. 2024.
"Kidney Infection - Symptoms and Causes." Mayo Clinic, 6 Aug. 2022, www.mayoclinic.org/diseases-conditions/kidney-infection/symptoms-causes/syc-20353387. Accessed 25 Sept. 2024.
Kiel, Raphael, et al. "Does Cranberry Juice Prevent or Treat Urinary Tract Infection?" Journal of Family Practice, vol. 52, no. 2, Feb. 2003, pp. 154-155.
O'Callaghan, C. A., and Barry M. Brenner. The Kidney at a Glance. Malden, Mass.: Blackwell Science, 2000.
Parker, James N., and Philip M. Parker, eds. The 2002 Official Patient’s Sourcebook on Pyelonephritis. San Diego, Calif.: Icon Health, 2002.
Walsh, Patrick C., et al., eds. Campbell-Walsh Urology. 4 vols. 9th ed. Philadelphia: Saunders/Elsevier, 2007.