Anomalies of the kidneys are intrauterine disorders of the development of organs in the fetus, which can threaten life and health or not interfere with full-fledged life. Pathologies of the kidneys of a congenital nature are a violation of the structure of the organ, its vessels, localization or performance. The main causes of kidney abnormalities are genetic abnormalities during the prenatal formation of internal organs and systems (first trimester of pregnancy). Also, harmful factors affecting a pregnant woman can negatively affect the excretory system of the unborn baby.
Causes of Renal Anomalies
Defects of the organs of the excretory system are diagnosed more often than other congenital disorders. The thing is that an anomaly in the development of the kidneys (according to ICD-10 code Q63) is not only accompanied by pronounced symptoms, but also has a negative effect on the functioning of other systems in the body. Together with the kidneys, the fetus most often develops a liver.
In the process of laying and differentiating tissues at the stage of maturation of embryonic cells, a certain malfunction occurs, which causes the formation of internal organs with deviations. Pathology can occur due to the effect on the fetus of various endogenous and exogenous factors:
- potent drugs (antibiotics, corticosteroids, ACE inhibitors, etc.);
- radioactive study;
- pathogenic microorganisms (viruses, bacteria, fungi, protozoa).
A cause of congenital malformations of the kidneys in children may be a genetic malfunction. In this case, a deviation in the development of the excretory system is combined with violations of a different localization, which leads to the formation of various syndromes. Depending on the process during which the violation occurred, a certain defect occurs (dysplasia, dystopia and other kidney pathologies).
All deviations of intrauterine kidney formation can be divided into:
- quantity anomalies (single and bilateral agenesis and aplasia of the kidney, doubling and the presence of a third additional kidney);
- structural disorders (dysplasia, kidney cyst - irregular structure of the kidney tissue);
- pathology of the situation (renal dystopia, that is, omission of the organ or its location in an atypical place, for example, below the lower back).
Most congenital abnormalities are combined with other abnormalities of the genitourinary system. Some of the genetic kidney defects can be absolutely incompatible with life, while others can carry a hidden danger to health, so any unnatural changes in the internal organs require constant monitoring.
Symptoms of Congenital Pathology
An abnormally developed or improperly located kidney, as a rule, does not have any specific manifestations. The symptomatic picture in most cases is absent, and the pathology is confirmed by chance, often during an ultrasound scan, prescribed for a completely different reason.
The situation is slightly different in the presence of bilateral defects: they are usually found in a short period after childbirth due to partial or complete organ dysfunction. The most dangerous anomaly of kidney development in children is agenesis, and in some cases even a one-sided form can lead to fetal death in the womb. If this violation occurs, then, most likely, during the first months and years of life, it will lead to severe renal failure. Such an anomaly can be suspected in the presence of malformations of the skeleton and other internal organs.
Speaking about such disorders as hypoplasia, an additional renal lobule, or polycystosis, it is worth noting that they are accompanied by signs of pyelonephritis, resulting from a violation of the outflow of urine. Children usually complain of soreness in the lower back, possibly an increase in body temperature and symptoms of intoxication. Anomalies in the relationship of the kidneys are accompanied by arterial hypertension. With increasing pressure at an early age, the first thing to exclude is a malfunction in the renin-angiotensin system.
An additional segment of the kidney is an abnormality in the development of an organ, which is characterized by urinary incontinence and frequent colic. Most often, the reason for contacting specialists in this case is hematuria, a change in the color and transparency of the urine.
Diagnostics
A study of the internal organs and systems of the unborn baby is carried out in the period from 12 to 16 weeks. During this period, it is already possible to identify most of the possible abnormalities of the kidneys in the fetus. Ultrasound screening will indicate the presence of malformation due to improper laying at the location of paired organs or the absence of a bladder, which can also be considered a secondary sign of deviation of the excretory system.
In young children, the indication for a clinical diagnosis is the presence of relevant symptoms from the urinary system. Patients who come to the pediatrician with complaints, the doctor should prescribe general laboratory tests of urine and blood, which allow to evaluate the functionality of the organs and detect signs of the inflammatory process. If there is a suspicion of a bacterial etiology of secondary pyelonephritis , urine cultures are performed.
Diagnosis of kidney abnormalities in newborns and older children is carried out using instrumental procedures. First of all, an ultrasound is performed, on which it is possible to identify violations in the number, position of organs, and suspect dysplastic tissue disorders. If the object of the study is urinary function, excretory urography will become more informative, which will also help assess the structure of the pyelocaliceal system and indicate hydronephrosis. In addition, with suspected polycystic and ambiguous results from previous studies, CT or MRI is performed.
Vascular disorders
In ICD-10, the code for anomalies in the development of the kidneys, which was caused by poor blood supply to the organ, is code Q63.8 “Other specified congenital malformations”. It is because of problems with the vessels that the full outflow of urine from the organ is disturbed, as a result of which pyelonephritis often occurs, blood pressure rises, and renal failure develops.
When diagnosing a congenital anomaly of the vessels of the kidneys, first of all, it is necessary to differentiate it from tuberculosis, hematological and hepatological diseases. Vascular disorders are usually an accompanying phenomenon for malformation of the kidney itself. Conditionally, the pathologies of the vessels of the kidneys are divided into anomalies of veins and arteries. A defect in the formation of the main vessels of the excretory system can be:
- the formation of multiple vessels;
- the appearance of an additional artery, which is already the main one and is attached to the organ at the top or bottom;
- the presence of an additional blood vessel of a similar size;
- fibromuscular stenosis (narrowing of the lumen of blood vessels due to the intensive proliferation of cystic and muscle tissue);
- an artery having a knee-shaped shape;
- aneurysms.
Venous defects are multiple and additional veins, as well as a variant of the location of the vessels emerging from the front and back of the organ in an annular shape. An anomaly is considered to be extracaval confluence, and retro-aortic placement of the left renal vein, and the attachment of the right testicular vein to the kidney vessel. To detect such abnormalities, Dopplerography is prescribed. According to the results of the study, the doctor will be able to give an objective assessment of the condition of the renal vessels.
Agenesis
In the absence or deep underdevelopment of the kidneys, the fetus is not viable. The reason for such violations of the formation of the excretory system is a gene mutation or a powerful negative effect on the unborn baby in the mother’s womb.
The most favorable prognosis is given to children with mild renal abnormality. With the partial absence of one of the paired organs, the quality of life does not change. A healthy kidney performs a double amount of work, completely compensating for the second dysfunction. Pathology may not manifest itself throughout life.
With the complete absence of kidneys (bilateral agenesis), it is impossible to live. Such children are born dead or die in the first days after birth. Immediate transplantation can save them.
Aplasia
Unlike agenesis, this pathology is a partial absence of one of the organs. Even if the anomaly is not noticeable in the shape of the kidneys, this does not always mean that the organ is fully developed. For an incompetent share, all functions are performed by the healthy part. If the kidney copes, and the excretory system does not fail, the patient may not be aware of the presence of a problem, since no symptoms are manifested with this form of aplasia.
Most often, a pathology is detected by accident, but no treatment is prescribed. The patient is recommended to undergo an ultrasound scan annually, take blood tests, urine tests and lead a healthy lifestyle. It is important to follow a sparing diet and abandon bad habits. If a healthy organ does not cope with the increased load, the patient will have characteristic symptoms that will indicate the need for urgent treatment.
Other organ abnormalities
Pathology consists in the congenital formation of an additional organ - the third kidney. Such an anomaly is a rarity in medical practice, especially if the additional share is fully functional and properly developed. The structure of the third organ is no different from the main one; it is also endowed with a separate blood supply.
The third kidney is located on the right or left side under one of the paired organs. However, its size may be slightly smaller, but this is not an anomaly of development. An additional segment of the kidney does not interfere with the life of the body. In isolated cases, the patient may begin to leak urine. Deviation is detected by chance during an ultrasound, the need for which arose during unsatisfactory blood and urine tests showing the presence of inflammation. In chronic pyelonephritis, an additional organ can be removed.
Hypoplasia deserves special attention - this is a pathological phenomenon in which one or both kidneys do not grow to normal due to their underdevelopment. At the same time, the functionality and histological structure of organs does not have any differences. The only difference is the smaller vascular lumen. Mostly only the proportion of the kidney is affected. The need for treatment arises only in cases where glomerulonephritis develops.
Violations of the formation of the renal pelvis
Abnormal doubling and bifurcation of the kidneys occurs quite often. Deviation in most cases occurs at the genetic level. However, there are also acquired anomalies of bifurcation of the kidney, which develop before birth, but after the laying of organs. The violation consists in a partial doubling of the pelvis and ureter, which are connected in one before the bladder, or complete bifurcation - in this case, two independent ureters lead to the bladder.
Pathology can develop from one or two sides at once. Diagnosis of the anomaly is possible using general and bacteriological analyzes of urine, ultrasound screening, urography, cystoscopy. This pathology is treated only surgically. The size of the bifid kidney is usually larger than normal, and the upper and lower sections are separated. Each organ fragment is supplied with blood equally. Renal anomaly can be partial and often leads to complications in the form of pyelonephritis, connective tissue tuberculosis.
Organ dystopia
In the prenatal period, the fetal kidneys can move to the lumbar region or, conversely, rise into the chest cavity. Changing the position of the organs is called dystopia.
This deviation can affect only one or both lobes. This defect is the most common. It is not life threatening and is not a deadly disease. At the same time, displacement can bring serious discomfort and threaten the full functioning of the excretory system, abdominal organs and small pelvis. An anomaly in the position of the kidneys can be of several types:
- Lumbar - the organ is palpated in the lower hypochondrium, blood vessels pass perpendicularly.
- Iliac - the lobe is localized in the ileum, it is fed by many branched vessels, pain in the lower back is possible.
- Pelvic - with this anomaly, the location of the kidneys negatively affects the work of the rectum and gall bladder.
- Thoracic - the renal lobe rises into the chest cavity, most often on the left side.
- Cross - this is a congenital defect, suggesting the displacement of one of the kidneys closer to the other, as a result of which both organs are localized on one side, their fusion is not excluded.
Horseshoe and biscuit shape
The causes of such pathologies, as described above, are congenital changes at the genetic level. Violations are laid during pregnancy. The anomaly of the horseshoe-shaped kidney is its fusion of the two ends together, as a result of which the organ takes the form of a horse horseshoe.
Often an ultrasound examination allows you to determine that this organ is localized below normal, while its blood supply is not changed. With abnormalities of fusion of the kidneys, the junction can compress the vessels and nerve roots in an uncomfortable position. A characteristic symptom in this case is a sharp paroxysmal pain. With a horseshoe-shaped form, inflammatory processes often occur in the structure of the organ, which quickly become chronic. Pathology is treated exclusively by surgery, without the use of medications.
Galette-shaped kidneys are another type of kidney relationship abnormality that occurs during pregnancy. For such a defect, the fusion of both kidneys is characteristic of each other. The organs are connected by the medial edges, while the pathology itself is localized in the midline of the spinal column in the pelvic region. The fusion site is easily palpated by palpation of the abdomen. You can determine this kidney anomaly when viewed on a gynecological chair. For the diagnosis, the same diagnostic methods are used as for dystopia.
Violation of the structure of the kidney
The altered structure of the organ can also be a defect inherent in the fetus. Congenital malformations of the kidney structure in children develop under the influence of teratogenic factors (potent drugs, narcotic substances, intoxication of the body, etc.). A consequence of these deviations in the structure of the organ is a predisposition to inflammatory and infectious processes. Treatment involves surgery. Structural renal abnormality may be:
- cyst;
- dysplasia;
- congenital hydronephrosis;
- hypoplasia.
Single cystic formations
If we are talking about the presence of only one benign tumor, it is called solitary. The cyst is formed in utero, but it can also be acquired, localized on the surface of the organ or inside it. As a rule, the neoplasm has a rounded shape.
Over time, the cyst increases in size, provokes atrophy and negatively affects the functioning of the organ. Anomalies are accompanied by dull lumbar pain and an increase in organ size. Pathology can be seen on an ultrasound or x-ray. This defect can be cured only by surgical excision of the neoplasm, but most often the cyst is left under long-term observation.
Multicystosis and polycystic kidney disease: what is the difference
In the first case, we are talking about the complete replacement of renal tissue with fibrous tissue, in the second - about abnormal compaction and numerous growths on the surface of the organ.
Multicystosis often affects only a fragment of one of the renal lobes. Pathology occurs if during the period of intrauterine development the fetus does not have an excretory apparatus. Urine is not fully excreted, its residues accumulate, which ultimately leads to the replacement of the parenchyma with connective tissue and cystic formations. With multicystosis, the renal pelvis also changes, sometimes it is completely absent. This violation is not hereditary and in most cases is detected by chance. With multicystosis, the kidney is felt through the stomach, especially with the parallel development of hypoplasia.
Symptoms of this disease include dull aching pain in the lower back.Possible increase in temperature to subfebrile values, flatulence. As a rule, a general analysis of urine does not show deviations from normal values, but changes will be noticeable on ultrasound.
Polycystic, unlike multicystosis, is most often transmitted genetically. This disease is very often accompanied by numerous formation of cysts in the liver, pancreas or other organs. If polycystic kidney disease is suspected, the examination is recommended not only to the patient, but also to all his close relatives, especially if the patient is a pregnant woman.
In severe cases, polycystic disease affects both renal lobes. Symptoms of polycystosis are not much different from multicystosis. In addition to them, the patient may suffer from constant thirst, loss of strength, fatigue. Polycystic is almost always accompanied by pyelonephritis, which in the absence of a full treatment can lead to atrophy and renal failure. The following diagnostic methods are used to confirm the pathology:
- ultrasonography;
- determination of the level of leukocytes in the urine;
- CT scan;
- X-ray examination.
With polycystic kidney disease, symptomatic therapy is performed. General recommendations include the exclusion of excessive and prolonged stress, the prevention of chronic infections (caries, acute respiratory viral infections, tonsillitis, sinusitis, etc.), adherence to a high-calorie, vitamin-rich diet with a restriction of protein and salt.
The danger of dysplasia
A deadly pathology that rarely goes without transplantation is kidney failure due to dysplastic tissue damage. With dysplasia, the size of the organ is less than usual. Improper growth and pathological intrauterine formation of the kidneys adversely affects the structure of the parenchyma and the functionality of the organ in the future.
Dysplasia can be dwarf and rudimentary. In the first case, the small size of the organ and the absence of the ureter are meant. Rudimentary dysplasia involves stopping the development of the kidneys in the first trimester of pregnancy. Instead of a kidney, the fetus has a small amount of connective tissue in the form of a cap on the ureter. A newborn child with such a pathology is doomed.
The prognosis for abnormalities in the development of the kidneys is favorable if the functions of the urinary system remain normal. The exceptions are gross malformations and bilateral anomalies, in which urgent organ transplantation or permanent hemodialysis procedures are required. Prevention of deviations in the development of the excretory system is carried out during pregnancy.