Overview of urinary tract infections (UTI)
Urinary tract infections are caused by direct invasion by bacteria (and rarely by fungi, protozoa, and viruses). Urinary tract infections are divided into upper and lower urinary tract infections. Upper urinary tract infections refer to pyelonephritis and lower urinary tract infections include urethritis and cystitis. Pyelonephritis is divided into acute pyelonephritis and chronic pyelonephritis. It is more common in women.
Causes of urinary tract infections
Urinary tract infections are caused by direct invasion by bacteria (rarely by fungi, protozoa, and viruses).
Symptoms of urinary tract infection
I. Acute pyelonephritis: 1.
1, the onset of the disease is rapid;
2, chills, chills;
3, fever;
4, general malaise, headache, weakness;
5, loss of appetite, nausea, vomiting;
6.Urinary frequency, urinary urgency, painful urination;
7.Lumbar pain, discomfort in the kidney area;
8.Ureteral point pressure pain;
9.pressure pain at the point of rib and waist;
10.percussion pain in the kidney area;
11.Pressure pain in the bladder area.
Second, chronic pyelonephritis.
1, the performance of acute attacks can be the same as acute pyelonephritis, but usually much lighter, even without fever, general malaise, headache and other systemic manifestations, urinary frequency, urinary urgency, urinary pain and other symptoms are not obvious;
2, edema;
3, hypertension ;
Third, bladder, urethritis.
Urinary frequency, urinary urgency, painful urination, pain in the bladder area. Urethral discharge.
Classification of urinary tract infections
(a) According to the site where the infection occurs, urinary tract infections are divided into upper urinary tract infections and lower urinary tract infections.
Upper urinary tract infection mainly refers to pyelonephritis, an infectious inflammation of the renal parenchyma and renal pelvis due to bacterial invasion of the kidney. Pyelonephritis is clinically divided into acute pyelonephritis and chronic pyelonephritis. Most acute pyelonephritis is caused by pathogenic bacteria reaching the kidney via the bladder and ureter, causing inflammation, mainly acute interstitial inflammation and varying degrees of necrosis of renal tubular epithelial cells.
Regarding the definition of chronic pyelonephritis, most scholars currently believe that this diagnosis has been overused in the past and that chronic pyelonephritis should be limited to those with clear inflammation, fibrosis and deformation of the renal pelvis and calyces. If this diagnostic criterion is used, the vast majority of chronic pyelonephritis is the result of urinary tract infection attached to urinary tract obstruction, poor urinary flow, or bladder-ureteral reflux. In the absence of these conditions, urinary tract infections often do not cause severe chronic kidney disease.
Therefore, acute and chronic pyelonephritis should be differentiated not by the length of its course or the number of recurrent episodes, but by the presence or absence of deformation of the pelvic calyces on imaging.
Lower urinary tract infections are mainly urethritis (urethritis) and cystitis (cystitis), in which the infectious inflammation is confined to the urethra and bladder.
(B) According to the presence or absence of functional or anatomical abnormalities of the urinary tract, urinary tract infections are divided into complex urinary tract infections and simple urinary tract infections.
Complex urinary tract infections are defined as.
(i) organic or functional abnormalities in the urinary tract, causing urinary tract obstruction and poor urinary flow;
② Foreign bodies in the urinary tract, such as stones, indwelling catheters, etc;
③ obstruction in the kidney, such as urinary tract infection occurring on the basis of chronic renal parenchymal disease, mostly pyelonephritis, which can cause kidney tissue damage. Long-term recurrent infections or incomplete treatment can progress to chronic renal failure (CRF).
Pawlowski et al. found chronic pyelonephritis in only 3.1% of 4596 autopsies, and therefore concluded that adult pyelonephritis, if simple, rarely causes end state renal diseas (ESRD) or pathological chronic pyelonephritis. (c) Based on the medical history, it is important to consider the risk of chronic pyelonephritis.
(c) According to the medical history, urinary tract infections are subdivided into primary and re-infection, the latter being subdivided into recurrence and reinfection.
Primary urinary tract infection is the first episode; recurrence refers to incomplete treatment, often within 6 weeks after discontinuation of medication, with the same strain and serotype of bacteria as the original infection, mostly seen in pyelonephritis;
Reinfection means that the original infection has been cured and is re-infected by a different strain of bacteria, often occurring 6 weeks after discontinuation of the original treatment, most often in cystitis. Frequent recurrences must be searched for.
In the past, urinary tract infections studied in the clinic mostly referred to infections caused by bacteria in general, and E. coli in particular. In recent years, with the development of medical research, there has been a new understanding of L-type bacteria, fungi, parasitic urinary tract infections and specific urinary tract infections such as those complicated by men, pediatrics, pregnancy, and chronic renal failure.
What tests are needed for urinary tract infections
1, pressure pain at the rib and waist point, percussion pain in the kidney area;
2, routine urine examination, urinary leukocytosis, pus urine;
3, urine sediment smear staining, find bacteria;
4, urine bacterial culture to find bacteria;
5, urine colony count >10 of 5/ml, with urinary frequency and other symptoms, >10 of 2/ml is also meaningful; coccus 10 of 3-10 of 4/ml also has diagnostic significance;
6, one hour urine sediment count leukocytes > 200,000;
7.Blood count shows elevated white blood cells and left shift of neutrophil nuclei;
8.Blood sedimentation is increased.