A urinary tract infection (UTI) occurs when bacteria enter and multiply within any part of the urinary system, which includes the kidneys, ureters, bladder, and urethra. While most UTIs are confined to the bladder or urethra, causing localized discomfort, a severe, untreated UTI can indirectly affect the liver. Direct infection of the liver by UTI-causing bacteria is rare. However, if the infection spreads throughout the body, the liver can become stressed or damaged as a result of the body’s overwhelming response to the systemic infection. Prompt recognition and treatment of UTIs are therefore important to prevent such serious complications.
How Untreated UTIs Can Progress
A UTI typically begins in the lower urinary tract, affecting the urethra (urethritis) or bladder (cystitis). If left untreated, the bacteria can ascend through the ureters, the tubes connecting the bladder to the kidneys, leading to a kidney infection, also known as pyelonephritis. This progression can occur within days to a week.
A kidney infection is a more serious condition because the kidneys play an important role in filtering waste from the bloodstream. If the infection continues to spread from the kidneys, bacteria can enter the bloodstream, leading to a life-threatening condition called urosepsis. Urosepsis, a type of sepsis originating from a urinary tract infection, signifies a severe systemic response that can lead to widespread inflammation and organ dysfunction.
How Severe Infections Affect the Liver
When a severe infection, like urosepsis, spreads throughout the body, it triggers a powerful immune response that can impact various organs, including the liver. The liver is a large organ with multiple functions, including detoxification, metabolism, and immune regulation. In the context of a severe systemic infection, the liver can become stressed due to several mechanisms.
One primary mechanism involves widespread inflammation. The body’s immune system releases a large number of inflammatory mediators to fight the infection, but an excessive inflammatory response can damage liver cells. Additionally, bacterial products and toxins can directly or indirectly cause liver injury. Reduced blood flow to the liver, often seen in severe sepsis due to circulatory disturbances, can also lead to liver damage by depriving liver cells of oxygen and nutrients.
Liver dysfunction occurs in a significant percentage of patients with sepsis. This can manifest as acute liver injury or dysfunction, where the liver’s ability to perform its normal functions is impaired. The liver’s involvement is typically an indirect consequence of the systemic inflammatory response to the infection, rather than the UTI bacteria directly infecting the liver tissue.
Key Indicators of Severe Infection and Liver Impact
Initial UTI symptoms often include frequent urination, a burning sensation during urination, cloudy or strong-smelling urine, and pelvic pain. If the infection becomes severe, additional symptoms may appear.
Signs of a serious systemic infection, such as urosepsis, include a high fever or unusually low body temperature, chills, rapid heart rate, and low blood pressure. Other indicators can be extreme fatigue, nausea, vomiting, confusion, or changes in mental status. If the infection has spread to the kidneys (pyelonephritis), individuals may also experience pain in the lower back or flank area.
When the liver is affected, specific symptoms might emerge. These can include jaundice, which is a yellowing of the skin or eyes, dark urine, or pale stools due to impaired bile processing. Severe fatigue, persistent nausea, vomiting, and pain in the upper right abdomen can also suggest liver involvement. Any of these more severe symptoms warrant immediate medical attention.
Preventing Serious UTI Complications
Prompt medical treatment for a UTI is important to prevent its spread. If antibiotics are prescribed, complete the entire course as directed, even if symptoms improve. This ensures bacteria are eliminated and reduces the risk of recurrence or antibiotic resistance. General prevention strategies also help, including drinking plenty of water, urinating frequently, and maintaining proper hygiene, such as wiping front to back. Urinating after sexual activity can also help remove bacteria.