What Happens If a UTI Goes Untreated for a Week?

An untreated UTI after one week can progress from uncomfortable urination to serious kidney complications. The infection may spread upward from the bladder to the kidneys, causing pyelonephritis with symptoms like high fever, severe back pain, and nausea. Studies show that 20-30% of untreated lower UTIs develop into kidney infections within days to weeks. Blood poisoning (sepsis) becomes a risk if bacteria enter the bloodstream, particularly dangerous for pregnant women, elderly patients, and those with compromised immune systems. Early antibiotic treatment typically clears UTIs within 3-5 days, making prompt medical attention crucial for preventing these serious complications.