What are urinary tract infections and how are they treated?

Urinary tract infection (UTI) is a collective concept that combines various infections of different parts of the urinary system. As an infectious disease, it is defined as inflammation of urothelium that occurs in response to the appearance of pathogenic microorganisms in the urinary system. Contingent on the localization, inflammation can affect the urethra, bladder (cystitis), ureters, and kidneys (pyelonephritis).

Short information about urinary tract infections

Most often, the infection starts in the bladder, getting there through the urethra, and then it can extend to the kidneys. Bacteria usually act as pathogens, from which a healthy organism without pathologies in most cases gets rid on its own. The usual causative agent of infection is Escherichia coli, which normally lives in the human intestine and can be introduced from there into the urethra.

UTIs are not transmitted from one person to another with the exception of sexually transmitted infections. But certain factors raise the risk of infection and complicate its treatment.

Such factors include:

- Permanent catheter,
- Urolithiasis,
- Neurogenic bladder,
- Vesicoureteral reflux,
- Obstruction of the urethra,
- Pregnancy,
- Diabetes mellitus,
- Renal failure,
- Immune suppression after a kidney transplant.

Moreover, the risk of UTI is higher in women, since their urethra is much shorter than in men and is located closer to the anus.

UTIs are often found among women, children, and the elderly, and are diagnosed based on symptoms and is confirmed through test strips, for example, when passing a general urine test. Treatment is usually carried out with antibiotics, for the correct purpose of which urine culture or its microscopic examination can be performed. In this case, a full course of treatment is carried out, even if the symptoms have disappeared earlier.

Normally, human urine is usually sterile, and the urethra is designed so that the bacteria cannot penetrate upward towards the kidneys. Therefore, most infections are limited to the bladder and are not very dangerous. However, in the absence of treatment, the infection can extend to the kidneys over time, causing a more serious disease that requires immediate treatment.

UTIs are the most frequent bacterial diseases among kids, and the lack of proper therapy can cause serious diseases, including scarring of the kidney tissue, which can lead to far-reaching consequences.

Symptomless bacteriuria not causing inflammatory processes and common for school-age children and women, but can also be detected in young kids, is distinguished from symptomatic UTI. UTI differs from symptomless bacteriuria by the leukocytes or pus found in the urine. In most cases, bacteriuria goes away on its own without any treatment for several months, and can only go into an infection with typical symptoms in very rare cases. Also, symptomless bacteriuria does not precede the onset of symptomatic infection and is not a sign of its development, thus it is customary to consider it separately.

Symptoms of UTIs

The most frequent symptom in kids is fever without an established cause. In children at the age of the speech stage of development, inflammation of the lower part of the urinary system is indicated by incontinence, dysuria (pain or difficulty urinating), and rapid urination. However, these same symptoms may indicate other diseases, including vulvovaginitis, enterobiosis (pinworm infection), crystalluria, and functional disorders of urination. High body temperature or pain in the lower back may also indicate that inflammation affects the renal parenchyma.

In adults, a bladder infection may manifest in:

- Cloudy urine or urine with blood;
- Strong or unpleasant smell of urine;
- Elevation in body temperature in some people;
- Burning or pain during urination;
- A feeling of pressure or cramping in the lower abdomen;
- A strong desire for frequent urination.

The extension of infection to the kidneys may be indicated by:

- Chills or night sweats;
- Fatigue and malaise;
- Temperature above 38.3 C (100.94 F);
- Pain in the lower back or groin;
- Redness of the skin;
- Changes in the state of consciousness or confusion of consciousness;
- Nausea and vomiting;
- Severe abdominal pain.

In case of possible signs of kidney infection, in particular, lower back pain, chills, fever, or vomiting, it is advised to consult a doctor immediately.

Diagnosis of UTIs

A preliminary diagnosis can be made through a general urinalysis, microscopic examination, or bacterial culture. In a general urinalysis, tests for leukocyte esterase or nitrites may indicate an infection, and a negative result from both tests does not guarantee the absence of infection. Confirmation of the preliminary diagnosis can be a positive result of a general urinalysis together with the finding of pathogens in the urine.

Urine culture is often done in the diagnosis of children, but in the case of adults, it is usually not done. In the case of children, it is believed that the diagnosis should be proven since a correct diagnosis helps prevent unnecessary interventions in the diagnosis, as well as unnecessary or incorrect treatment.

Symptomless bacteriuria is diagnosed if urine tests showed the bacteria in it, but a general urinalysis did not reveal signs of an inflammatory process.

Differential diagnosis

UTI in kids under two years of age can be suspected with unreasonable high temperature. In such cases, it is recommended to conduct a urine test to exclude infection. In kids from 2 years of age, infection is likely in the pain in the abdomen or lower back, fever, dysuria or frequent urination, or incontinence. Urinalysis is also required to confirm infection with these symptoms.

Therapy of urinary tract infections

Therapy of a urinary tract infection involves eradicating the infection to prevent possible complications. It is carried out by the use of antimicrobial agents based on the sensitivity of the pathogen if it is known to which drugs it is sensitive.

Moreover, in children over 2 years of age, antibiotic treatment is not recommended if leukocytes or nitrites are not found in the urine, and there are no infection-specific symptoms.

Symptomless bacteriuria does not require antibiotic treatment, since in this case the harm from treatment may exceed the benefit.

Due to the spread of bacteria with mechanisms that make them resistant to certain antibiotics, UTIs have become quite difficult to treat. Thus, it is advisable to use modern antibiotics such as Azithromycin.