Kidney infections occur when bacteria get into the urinary tract and migrate upwards, infecting the bladder and sometimes the kidneys, too. “The most common bacteria involved are E coli,” said Dr. Ingride Richardson, an assistant professor of urology at the University of Pennsylvania Health System. “As part of their structure, the bacteria have ‘arms’ that allow them to climb up the urethra and spread to the kidneys.”
In the vast majority of cases, urinary tract infections (UTIs) don’t spread to the kidneys, according to Dr. Sarah Flury, a urologist at Northwestern University. There are about 6 million urinary tract infections each year in the United States and about 250,000 kidney infections, Flury added.
So, why then have you developed a kidney infection?
There are several factors that can increase your risk, experts say.