The term urinary tract infection refers to a range of clinical situations, from asymptomatic bacteriuria to severe purulent inflammation of the kidneys, which can result in sepsis (blood poisoning). Urinary tract infections are among the most common infectious diseases and are considered to be a major problem for society. There are 4 ways bacteria enter the genitourinary system. It is generally accepted that the ascending entry of bacteria from the urethra into the urinary system causes the vast majority of cases of urinary tract infections.

In most cases, pyelonephritis (inflammation of the kidneys) is caused by pathogens that have penetrated from the bladder through the ureters into the kidneys. Thus, the short female urethra and its physical proximity to the vagina and anus lead to a higher incidence of urinary tract infections in women.

Other routes of entry of microbes into the urinary system are much less common. Hematogenous (through the blood) spread can occur in adults and children who are immunocompromised. Bacteria spread in this way include Staphylococcus aureus, Candida and Mycobacterium tuberculosis. It is also known that pathogens of urinary tract infections can be spread by the lymphatic, intestinal and periureteral lymphatic tracts, but there is no reliable data that would suggest that this method plays a significant role in the development of urinary tract infection. (urinary tract infection)

Direct penetration of microbes from neighboring organs into the urinary system can occur with intra-abdominal abscesses, vesico-intestinal or vesico-vaginal fistulas. Incompletely treated prostate or kidney infections can spread to other parts of the urinary tract.
Urodynamic disorders play an important role in the development of urinary tract infections. Obstruction of the outflow of urine, reflux can contribute to the growth of bacteria and the development of infection. Therefore, any anatomical defect that prevents the outflow of urine increases the likelihood of developing urinary tract infections. Obstructive conditions include urolithiasis, tumors, diabetes, and pregnancy. The presence of foreign bodies in the urinary tract, such as stones, catheters, and stents, contributes to the development of infection. (urinary tract infection)

Causes (urinary tract infection)
Urinary tract infections are usually caused by a single bacterium entering the urinary tract. 80% of uncomplicated cystitis and pyelonephritis is caused by Escherichia coli type O (E. coli). Less commonly, urinary tract infections are caused by: Klebsiella, Proteus and Enterobacter pathogens. Nosocomial pathogens also include Pseudomonas and Staphylococcus species. Staphylococcus aureus is most often spread by the hematogenous route (through the blood). Group B beta-hemolytic streptococci often cause urinary tract infections in pregnant women. In children, pathogens of Klebsiella and Enterobacter are often found. Anaerobes, lactobacilli, corynebacteria, and bacteria such as Staphylococcus epidermis are often found in the cystic area. (urinary tract infection)

Diagnosis of urinary tract infections is carried out by general and bacteriological examination of urine. A general urinalysis can detect urinary tract infections very quickly.

Microscopic examination of urine is carried out after urine centrifugation. Nitrites and esterases in the urine, resulting from the breakdown of leukocytes and bacterial activity, can be detected using dipstick tests. The "gold standard" for detecting urinary tract infections is a bacterial urinalysis. The urine sample should be collected in a sterile container and examined as soon as possible.

Symptom (urinary tract infection)

Fever is characteristic of urinary tract infections. Fever is common in pyelonephritis (inflammation of the kidney), prostatitis (inflammation of the prostate), and orchiepididymitis (inflammation of the testis and scrotum), but fever is not characteristic of cystitis (inflammation of the bladder).

With inflammation, the patient may experience pain that can be localized in the lumbar region with inflammation of the kidney, in the area of ​​the pubic symphysis with inflammation of the bladder, with inflammation of the prostate gland, pain can be localized in the area of ​​the pubic symphysis or in the perineum, and with inflammation of the testicle and epididymis, pain located in the scrotum. (urinary tract infection)

If necessary, conduct instrumental studies. Ultrasound is considered a non-invasive and quick way to identify a possible inflammatory focus, in some difficult cases it is performed using computed tomography.