A new way of looking at UTIs
Urinary tract infections (UTIs) are a common reason people visit their doctor. They are estimated to account for around 1 to 5 out of every 100 visits to primary care clinics.
UTIs are usually grouped into two types: uncomplicated and complicated. The idea of “complicated UTIs” was first introduced in 1963 and later updated in 1992 by two major medical groups — the Infectious Diseases Society of America (IDSA) and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID).
What Makes a UTI “Complicated”?
Urinary tract infections (UTIs) are called complicated when they occur in people who have issues with how their urinary tract works or is built, have weakened immune systems, are male, or are pregnant. However, this current definition does not fully take into account how severe the infection is, some important risk factors, or the type of bacteria causing it. These factors can make it more difficult to choose the right antibiotics, often mean that treatment takes longer, and can increase the risk of serious problems like kidney damage or sepsis. They are all important in deciding whether a UTI is truly complicated.
A New Way to Classify UTIs
The European Association of Urology (EAU) Guidelines Panel has reviewed this topic and suggests updating how we define and classify UTIs. The goal is to make diagnosis clearer and treatment decisions easier. The panel highlights two important points:
- A patient's general health should be taken into account.
- Doctors should look closely at each patient's personal risk factors.
The ORENUC Risk Classification
To help decide how “at-risk” someone is, the panel suggests using the ORENUC system, especially for patients who keep getting UTIs. This system places patients into six groups:
- O – No known risk factors
- R – Risk factors for recurrent UTIs (UTIs that keep coming back)
- E – Risk factors outside the urinary system (like diabetes)
- N – Kidney-related conditions
- U – Urinary tract problems that can be treated
- C – Catheter-related risks
Localised vs. Systemic UTIs
The panel also proposes dividing UTIs into two categories based on symptoms:
- Localised UTI: A bladder infection without signs that the infection has spread. Typical symptoms include pain when urinating, needing to go often or urgently, and lower belly pain.
- Systemic UTI: An infection that has spread beyond the bladder and causes whole-body symptoms such as fever, chills, confusion, low blood pressure, rapid heartbeat, or pain in the back near the kidneys.
Both types can occur in people who have extra health risks, such as:
- Children or frail elderly people
- Urinary tract abnormalities
- Use of a urinary catheter
- Kidney or bladder stones
- Weak or weakened immune system
- Trouble emptying the bladder
- Nerve-related bladder problems
- Recent use of antibiotics
- History of resistant bacteria
- Blockage in the urinary tract
- Weakened, damaged or inflamed bladder lining
- Recent surgical procedures involving the urinary tract
- Enlarged prostate
- Pregnancy
- Pelvic organ prolapse (when the muscles and tissues supporting the organs in the pelvis (like the bladder, uterus, or rectum) become weak or loose.
What This Means for Treatment
Usually, localised UTIs can be treated at home, even in men or women with some risk factors. But systemic UTIs often need stronger treatment, including antibiotics given through a vein (intravenously), and more tests such as blood work and imaging scans.
References
- This article is a simplified version of a medical news article originally published on the European Association of Urology website: https://uroweb.org/news/new-classification-of-utis-from-uncomplicated-complicated-to-localised-systemic-utis