By Board Certified Urologist Dr. Yana Barbalat
An embedded UTI is a term used to imply that an individual who has recurrent infections has a source of bacteria somewhere in their body that has not been properly treated and is, in a way, in hiding. However, “embedded UTI” is not a medical term.
Occasionally, a person can get a persistent UTI due to a persistent source of infection. Doctors call this a “nidus” for infection. Essentially, it is a place where bacteria can hide and evade antibiotics. In this case, a patient will have recurrent symptoms of an infection shortly after completing an antibiotic course. That is because the bacteria that is hidden comes back out and reinfects the urine.
Here are the common scenarios where we see a nidus for infection:
Presence of large urinary stones- Bacteria can hide inside kidney or bladder stones and can cause recurrent and persistent UTIs. This is the reason that if you have recurrent UTIs, your doctor may recommend a kidney or bladder ultrasound. An ultrasound would reveal any large stones that may be present in the urinary system.
Foreign body in the urinary system- These include indwelling catheter, stents in the ureters, vaginal mesh that has migrated into the bladder or urethra, or old non-absorbable stitches from prior surgery. All these materials can cause bacteria to adhere to them and even form biofilm that is hard for antibiotics to penetrate.
Anatomical abnormalities of the urinary system- Every once in a while, there may be an abnormal space in the kidney, bladder, or urethra where urine can get hung up and accumulate. Usually, this is due to a blockage somewhere downstream. An example of this is hydronephrosis of the kidney (swelling of the kidney), a bladder diverticulum (a pocket coming off the bladder), or a urethral diverticulum (small pocket coming off the urethra). These areas can be thought of as a pool for bacteria to multiply in. If a person has poorly controlled diabetes, it becomes a sweet pool for bacteria, so they multiply even faster.
Chronic prostatitis- The prostate is an organ that is part of the urinary tract in men which antibiotics have a hard time penetrating. If you develop a prostate infection that is not adequately treated, the bacteria may persist in the prostate tissue. It will often re-infect the urine once antibiotics are stopped. Because of this, prostate infections should be treated with a much longer course of antibiotics than is typical for other UTIs.
Although many people who have recurrent UTIs think that there must be a source for their infections, we rarely find one. However, although most people do not fall into the categories above, any patient who has at least 3 UTIs per year, should have the proper work up to make sure that there is no specific source for their infections.
