If we turn to the WHO statistics, we can see that among all renal diseases, pyelonephritis occupies a dominant position. Almost every second person is diagnosed with latent chronic pyelonephritis. The direct danger of this disease is that it can lead to kidney failure. The latter significantly reduces the quality of life and sometimes leads to death.
In the article we will present the main classification of pyelonephritis, adopted by WHO (World Health Organization). Consider the characteristics of the disease, statistics. Let us describe the forms of the disease distinguished in the classification.
What is it?
Before considering the classification of pyelonephritis, we present a description of this disease. This is the name of the inflammatory process of an infectious nature that develops in the interstitial tissues and tubules of the kidneys. At the same time or in the future, it can also affect the parenchyma and pelvis of the kidney. At its final stage, the disease spreads to the glomeruli and blood vessels of the organ.
Pyelonephritis is also often called a bacterial variety of interstitial nephritis.
Statistics data
Next, we will present the WHO classification of pyelonephritis. But first, we’ll announce the statistics of the World Health Organization on this disease:
- The most common kidney disease, and in all age groups. As for children, pyelonephritis takes 2-3rd place in frequency of distribution, second only to respiratory diseases.
- Among the adult population, pyelonephritis is diagnosed in 100 people out of 100 thousand. Among children - in 480-560 people out of 100 thousand.
- 60-75% of cases are people of young, middle age (30-40 years). The disease often develops in them after defloration, pregnancy, in the postpartum period.
- In children, the peak incidence of pyelonephritis occurs at the age of 2-3 years.
- As for the "sex" of the disease, it is mainly female. Pyelonephritis is diagnosed more often in girls than in boys. This trend continues with age. Young women suffer from the disease 4-5 times more often than men. This is explained by the anatomical features of the genitourinary system.
- Pyelonephritis provokes mainly urolithiasis, urethral stricture, chronic prostatitis, abnormal development of the kidneys and urinary tract. As for older men, their disease can provoke an enlargement of the prostate gland, which makes it difficult to drain urine from both the kidneys and the bladder.
International Classification of Diseases
If we turn to the classification of pyelonephritis in the ICD-10, then we will notice that this disease is not allocated in the directory as a separate disease. It belongs to a subclass of pathologies of the tubulointerstitial renal apparatus. Pyelonephritis in the ICD-10 can be found under the codes N10-N13.
We will present special cases:
- N10. Tubulointerstitial acute jade. Infectious interstitial nephritis, pyelonephritis and pyelitis are distinguished.
- N11. Tubulointerstitial chronic nephritis. The category includes the same interstitial nephritis, pyelonephritis and pyelitis. There are additional subcategories of the listed diseases: N11.0 - non-obstructive origin associated with reflux, N11.1 - obstructive forms (except pyelonephritis, which are associated with urolithiasis), N11.2 - other forms of the disease, N11.3 - serious data forms chronic pathologies.
- N12. Tubulo-interstitial disease, in the case of which it is impossible to clarify its form - acute or chronic.
- N13. A number of obstructive disorders, among which stand out as obstructive pyelonephritis, and urolithiasis.
Clinical classification of pyelonephritis
For this disease, several pathways of infection, forms, flow patterns, and other features important to specialists are characteristic. Therefore, nephrologists decided to introduce a single gradation. It was voiced in 1974 at the First All-Union Congress of Nephrologists.
This is a classification of pyelonephritis according to N. Lopatkin, V. E. Rodman. The following varieties of the disease are distinguished:
- Unilateral and bilateral.
- Acute and chronic.
- Primary and secondary.
- Serous and purulent.
- Hematogenous and urinogenous.
- Obstructive and without obstruction.
There is a separate classification of acute pyelonephritis:
- Primary acute.
- Secondary acute.
- Acute pyelonephritis in pregnant women.
- Apostematous pyelonephritis.
- Carbuncle kidney.
- Abscess of the kidney.
Classification of chronic pyelonephritis is as follows:
- Actually the chronic form.
- Pyonephrosis
- Paranephritis.
- Necrosis of the renal papilla.
We will get acquainted with the presented categories of the disease in detail.
The number of affected kidneys
According to the number of affected kidneys, the classification of pyelonephritis is as follows:
In the first case, one kidney is affected, in the second - two. Such a gradation is characteristic of both acute and chronic forms of pyelonephritis.
Of course, with a unilateral course of the disease, its prognosis is more favorable, since one healthy kidney is able to provide a relatively high-quality cleaning of the body of toxins during the illness. Otherwise, pyelonephritis often turns into complications.
Conditions of occurrence
Classification of pyelonephritis according to the conditions of occurrence:
In the primary form, the pathogenic factor has a negative effect on the renal system immediately after it enters the body. In the case of secondary pyelonephritis, an infectious inflammatory process has already developed in any location of the body. Consequently, pathogens from it through migration got into healthy kidneys, provoked their inflammation.
Infection pathway
According to this classification, the pathway of infection that causes pyelonephritis can be as follows:
It is important to note that a homogeneous (through the blood) pathway of infection is more characteristic of acute pyelonephritis. In this case, the inflammatory process will be localized in the cortical substance, in the vicinity of intralobular vessels.
Urinogenous (through urine) infection is characteristic, respectively, for pyelonephritis in a chronic form. Pathogenic microflora here migrate from the lower urinary tract, moving along the wall or lumen of the ureter.
In this case, the locations of inflammation will be located fan-shaped. They have the form of wedges located with the tip to the side of the pelvis, and the base - to the outer surface of the kidney. Usually with urinogenous pyelonephritis, it is preceded by cystitis or urethritis.
Urinary tract
Here, the disease is also presented in the classification in two forms:
- Obstructive.
- No obstruction.
In most cases, obstruction (obstruction) is diagnosed when infection pathogens migrated to the kidney along the walls of the ureter. This leads to inflammation of the latter, which results in a narrowing of these walls, a decrease in the lumen of the ureter.
Accordingly, with obstructive form, pyelonephritis develops faster and harder. The disease may be accompanied by more pronounced intoxication of the body, since normal outflow of urine is difficult. It must be said that urine (stagnation of urine) creates favorable conditions for the propagation of pathogenic microflora. And poisoning the body with metabolic products depresses the immune system.
A kind of inflammation
In this subcategory, two types of pyelonephritis are distinguished:
- Serous.
- Purulent. This type includes the apostematous form, renal abscesses and carbuncles.
As for statistics, the first category of the disease is considered more common. Serous pyelonephritis - 70% of all cases of the disease, purulent - the remaining 30%. With serous inflammation, there is a thickening, swelling of the kidney. The organ is noticeably tense. In the parenchyma, foci of infiltration around the vessels develop. It is important to note that the serous form can turn into purulent over time.
For purulent pyelonephritis , an apostematous course is characteristic, in which multiple suppurations develop. White blood cells, neutrophils, and dead cells were noted in the infiltrates. This pathological mass squeezes the renal tubules.
Carbuncle here is one of the varieties of apostematous pyelonephritis. More precisely, this is its natural final stage. It is an enlarged purulent focus. Even with the full recovery of the patient, such a degree of pyelonephritis is fraught with negative consequences, because dead kidney cells are replaced by connective tissue. And this further provokes renal failure.
Acute classification
The classification of chronic pyelonephritis in adults will be presented below. Now consider the gradation of the acute form of the disease:
- Primary acute. So in the medical environment they call pyelonephritis, which developed without a previous disease of the renal or genitourinary system. In this form of the disease, pathogenic microflora penetrate the kidney through the hematogenous route (in other words, through the blood) from any infectious and inflammatory foci localized in the body.
- Secondary acute. This form of pyelonephritis can be preceded by the following: urinary tract abnormalities, stones in the bladder, pregnancy, strictures of both the urinary tract and the ureter, and an enlarged prostate gland. In children, a hemodynamic disorder is additionally distinguished.
- Acute pyelonephritis in pregnant women. It develops around the second half of the gestation period. The disease provokes the pressure of an enlarging uterus on the ureters, asymptomatic bacteriuria, decreased tone of the upper urinary tract, as a result of neurohumoral changes in the body.
- Apostematous form. This is an inflammation of purulent nature. Numerous pustules form in the renal cortex. This is a stage or complication of acute secondary pyelonephritis. A consequence of metastatic (spreading) infection with a pyogenic infection.
- Carbuncle kidney. Purulent necrotic organ damage. A limited infiltrate is formed in the kidney cortex. It may be the primary disease, the result of massive bacterial migration from the focus of inflammation.
- Abscess of the kidney. Pretty rare form.
Classification of the chronic form
Imagine a classification of chronic pyelonephritis:
- Actually the chronic form. The consequence of acute pyelonephritis. This is facilitated by the unremedied causes of obstruction to the outflow of urine, improper, inadequate treatment of the acute form of the disease, immunodeficiency, serious general diseases, infection by bacteria that are resistant to treatment, being in an inactive form.
- Pyonephrosis The thermal stage of a purulent-destructive form of the disease, both specific and non-specific.
- Paranephritis. The spread of inflammation in the perinephric adipose tissue.
- Necrosis of the renal papilla. A consequence of exacerbation of chronic pyelonephritis. The consequence of either embolism of blood vessels by pathogenic microflora, or the result of compression of these vessels by infiltrate.
Stages of the disease
You are familiar with the WHO classification of chronic pyelonephritis. In its course, this disease passes in three stages:
- Sharp.
- The period of latent inflammation.
- Remission (may be complete and incomplete).
The phase of the disease is recognized as acute based on the analysis of the patient’s blood and urine, the diagnosis of pronounced symptoms. As for the latent phase, then in its continuation the disease does not make itself felt. Clinical symptoms are mild, which allows us to judge the sluggish inflammatory processes.
The options for ending the disease are as follows:
- Recovery of the patient.
- Transition of acute to chronic.
- The development of secondary nephropathy.
- Diagnosis of secondary wrinkling of the kidney.
The possible consequences of the disease are as follows:
- Urosepsis.
- The acute occurrence of renal failure.
- Chronic occurrence of renal failure.
Classification for children
There are no differences. Classification of pyelonephritis in children is similar to an adult. The disease is divided into the same categories:
- Primary and secondary.
- Acute and chronic.
- Obstructive and nonobstructive.
You are already familiar with the characteristics of the listed varieties of pyelonephritis.
Pyelonephritis is a serious common kidney disease. You know its main varieties, which have their own characteristic features.