Balkan endemic nephropathy
The Balkan endemic nephropathy — not inflammatory tubulointerstitsialny defeat of a kidney parenchyma at the people living in endemic regions of the Balkans. It is shown by an asthenic syndrome, waist pains, pallor and a copper shade of integuments, a ksantokhromiya, a makrogematuriya, a polyuria, a polidipsiya. It is diagnosed by means of the general and biochemical blood tests, urine, ultrasonography, MPT, KT, MCKT of kidneys, the general and excretory urography, a nefrostsintigrafiya, a histologic research of a bioptat. Symptomatic antianemichesky, anti-ischemic, detoksikatsionny, replacement kidney therapy, renal transplantation is recommended to patients.
Balkan endemic nephropathy
For the first time the Balkan endemic nephropathy (BEN) was described as the Yugoslavian nephrite in 1942. In 1956 messages on detection of renal pathology with a similar clinical picture at residents of the Bulgarian and Romanian villages arrived. As independent nosological unit of BEN it was recognized as WHO experts in 1964. The majority of cases of not inflammatory tubulointerstitsialny nephrite is registered at residents of rural areas of the Balkan countries (Bulgaria, Bosnia and Herzegovina, Romania, Serbia, Slovenia, Croatia) located on inflows of Danube. Incidence in the centers reaches 30-33%. All endemic territories are on plains in an environment of hills or in , alternate with not endemic regions. The main contingent of patients is made by 30-60-year-old villagers. Up to 40-45 years of the woman suffer twice more often than men, late this distinction is leveled. At residents of the cities, children and teenagers the disease usually does not come to light. At early departure emigrants from the Balkan countries get sick seldom. At immigrants of BEN can develop in 15-20 years of accommodation in the center.
Reasons of the Balkan endemic nephropathy
The etiology of a disease is not finalized. Experts in the sphere of urology and nephrology develop several theories of an origin of pathology, each of which partially is confirmed statistical yielded and results of observations. Final establishment of the reasons of damage of kidneys at inhabitants of the Balkan region requires carrying out more large-scale researches. Can be presumably etiologichesky factors of an endemic nephropathy:
- Infectious agents. According to authors of virus and prionny theories of emergence of the Balkan tubulointerstitsialny nephropathy, the chronic progrediyentny current with the long asymptomatic period corresponds to symptoms of a slow infection. Indirect confirmation of infectious genesis of a disease is allocation of cytopathogenic agents from biological substrata of patients and a possibility of infection of laboratory animals (guinea pigs, rats). The BEN activator is not installed yet, however the role of bacteria in development of an endemic form of a nephropathy is already completely excluded.
- Nefrotoksichny mycotoxins. The theory according to which the endemic Balkan nephropathy is a chronic okhratoksikoz is rather convincing. As the main nefrotoksin ochratoxin A which is produced by some mold mushrooms is considered and gets into a human body with flour products from kontaminirovanny grain. The main arguments in favor of a mikotoksichesky origin of a disease — identification at residents of endemic regions of the increased concentration of ochratoxin in blood and similarity of patomorfologichesky changes to nephrological pathology at the animals suffering okhratoksikozy.
- Aristolokhovy acid. The theory of the American scientists connects development of the Balkan nephropathy with the use of the products polluted by seeds of a lomonosovidny birthwort. This weed in large quantities striking wheat fields of endemic territories contains the aristolokhovy acid having cancerogenic and nefrotoksichny properties. In confirmation of the theory data on development of "a grass Chinese nephropathy" in the Belgian patients accepting vegetable medicines with a birthwort are used. The theory does not explain lack of an endemiya in other regions where this plant is widespread.
- Pliotsenny lignites. In the majority of endemic territories deposits of Pliocene lignites — the youngest kind of brown coal on the Balkans are revealed. The aromatic amines provoking developing of uroepitelialny cancer are their part. As such lignites have friable structure, they are easily washed away by water and get to drinking wells of farms and rural settlements. Frequent development of planocellular cancer of mochetochnik and a lokhanok in the Balkan regions with high incidence of a nephropathy indirectly confirms a community of an etiology of these diseases, however lignites are revealed not in all endemic areas.
- Genetic factor. As the endemic option of a nephropathy often has family character, some researchers state the ideas about a role of hereditary predisposition. In their opinion, the inherited mutation increases sensitivity of a kidney mesenchyma to action of the nefrotoksichny modifying factors. It is not excluded that BEN is result of the dizembriogenetichesky violations leading to reduction of quantity of nefron and decrease in a functional reserve of kidneys. Identification at patients of changes in the 3rd chromosome became an argument in favor of the genetic theory.
The role of ecological factors in developing of endemic renalny pathology is separately studied. In samples of soil, drinking water, local food the increased concentration of some ions rendering nefrotoksichny effect are defined (vanadium, cadmium, manganese, copper, lead, chrome, etc.), a part of which in a large number is found in biological tissues of the died patients. The mechanism of development of a nephropathy at an imbalance of minerals and their dangerous combinations are not established yet. Besides, some urologists consider BEN as option of primary amiloidoz.
Though the mechanism of development of the Balkan endemic tubulointerstitsialny nephropathy is still specified, scientists managed to make rather full picture of the patomorfologichesky changes happening in kidneys. The expression of the mutating gene or modification of DNA under the influence of long action of a possible provocative factor (ochratoxin A, aristolokhovy acid, a virus, a prion, aromatic amines, etc.) becomes a push to frustration emergence most likely. In formation of sclerous processes autoimmune mechanisms can play an essential role.
The first nefrona usually are surprised: their basal membrane is thickened, extends mezangiya of balls. At the same time there are gidropichesky dystrophic changes in an epithelium of proximal tubules which are aggravated with a thickening, a gialinization, stratification of a basal membrane subsequently. Active growth of interweft connecting fabric leads to development of the extracellular and perivaskulyarny sclerosis amplifying at the expense of ischemia of a kidney parenchyma against the background of a thickening of walls of vessels, fibrosis their intims and asymmetric narrowing of a gleam. Processes of fibrosis, a sclerosis, gialinization of a stroma, atrophy of the majority of proximal tubules and a part come to the end with heavy nephrosclerosis with reduction of the sizes of kidneys by 2,5-4 times to 40-70 g.
Symptoms of the Balkan endemic nephropathy
The symptomatology accrues slowly, at the initial stages differs in not specificity. Usually patients with the Balkan nephropathy note weakness, bystry fatigue, deterioration in appetite, insignificant morbidity in lumbar area. In the subsequent discomfortable feelings amplify, the periods of weight and dull ache in a waist are replaced by painful attacks. Skin becomes pale, sometimes with a copper shade, on palms and soles gradually turns yellow. In process of progressing of a nephropathy the intolerance of physical activities, thirst, increase in a diuresis, dryness and insufficient turgor of integuments appear. Reddening of urine due to presence of erythrocytes is possible (makrogematuriya). Hypostases are observed extremely seldom. At 20% of patients arterial hypertension develops.
Because of early violation of synthesis of erythropoietin the endemic nephropathy at preclinical stages becomes complicated normo-or the gipokhromny anemia leading to a hypoxia of a brain, myocardium, other bodies and fabrics. The inhabitants of the Balkan region suffering from damage of kidneys, by 100 times more often than living in other territories, develop the high-differentiated perekhodnokletochny cancer a lokhanok and mochetochnik. This malignant new growth comes to light almost at 40% of patients with BEN, and at 10% of patients tumoral process is bilateral. At accession of an infection developing of pyelonephritis is possible. Regarding cases develops . The heavy renal failure leading to death from uraemia with toxic polyorgan frustration becomes an outcome of the Balkan nephropathy.
At diagnosis consider duration of residence in the endemic area, dynamics of increase of a clinical picture, data of laboratory and tool inspection. Diagnostic search is directed both to verification of a disease, and to assessment of a functional solvency of the kanaltsevy device. Diagnostics of the Balkan endemic nephropathy at a latent stage of a disease is usually complicated. At such patients the importance of geographical criterion significantly increases. The most informative methods of researches are:
- General analysis of urine. Reduction of specific weight of urine lower than 1003, a kanaltsevy proteinuria to 1 g/days with allocation mainly low-molecular β2-, and at late stages — α1-, α2-, β-, γ-globulins, a mikrogematuriya is characteristic. In collected material glucose often is defined.
- General blood test. An early diagnostic sign of BEN is anemia. At patients the general level of erythrocytes, hemoglobin decreases, at gipokhromny violation of blood formation the color indicator (CI) decreases. The maintenance of leukocytes, a ratio of their types, SOE are usually not changed.
- Biochemical blood test. Insufficiency of the filtering function comes to light at a late stage of a nephropathy. Serumal concentration of creatinine, uric acid, nitrogen of urea, macrocells increases. Violation of a renalny filtration is confirmed by Reberg's test.
- Nephrological complex. Already at a doazotemichesky stage of BEN ekskretion level with urine of amino acids increases, release of ammonium, uric acid is broken. At development of a renal failure the content in urine of creatinine, urea, potassium, sodium, calcium, phosphorus changes.
- Ultrasonography of kidneys. The Ekhografichesky research is more indicative at terminal stages of an endemic nephropathy: kidneys are symmetrically reduced in sizes, have uniform structure, do not contain kaltsinat. If necessary ultrasonography can be supplemented with a survey X-ray analysis, KT, MCKT, MPT of kidneys.
- Histology of a kidney bioptat. In the received material symptoms of dystrophy and an atrophy of proximal tubules, hypostasis of interweft fabric and an endoteliya of capillaries of a stroma are defined, single macrophages come to light. At late stages the morphological picture of a tubulointerstitsialny sclerosis prevails.
For assessment of the filtering ability of kidneys the excretory urography, a nefrostsintigrafiya can be carried out. The endemic Balkan nephropathy is differentiated with a chronic glomerulonefrit, pyelonephritis, an analgetic medicinal nephropathy, tsistinozy, an intoksikatsionny nephropathy owing to poisoning with mercury, salts of lead, cadmium. According to indications the urologist or the nephrologist involve in survey of the patient of the oncologist, toxicologist, therapist.
Treatment of the Balkan endemic nephropathy
Etiotropny therapy of a disease is not offered. Medical tactics is directed to correction of symptoms, a nefroprotektion, reduction of a progrediyentnost of BEN. For decrease in load of kidneys the refusal of hard physical activity, sufficient rest, restriction of consumption of salt, proteinaceous products, waters is recommended (taking into account a stage of the Balkan nephropathy). Depending on expressiveness of clinical manifestations and existence of complications the symptomatic therapy including is carried out:
- Protivoanemichesky means. Iron medicines, folic acid, erythropoietins, anabolic steroids can be applied to stimulation of blood formation. The patient with the expressed anemia sometimes pour eritrotsitarny weight.
- Anticoagulants and antiagregant. Improvement of rheological properties of blood and a renalny blood-groove allows to reduce ischemia and to slow down fibrosis a little. In terminal stages medicines of this group are not applied because of strengthening of bleeding.
- Detoxication. At the initial stage enterosorbents, protivoazotemichesky phytomedicines are used. At increase of a renal failure of patients transfer to replacement therapy (a hemodialysis, peritonealny dialysis, a haemo filtration, etc.).
- Transplantation of a kidney. Change of a donor organ — a radical method of treatment of the Balkan nephropathy at terminal stages. By results of observations, disease recurrence cases in a transplantirovanny kidney were not noted.
Forecast and prevention
The pathological processes in kidneys arising at an endemic nephropathy are irreversible and in the absence of medical care lead to death within 5-10 years from the moment of emergence of clinical symptoms of a disease. About a half of patients die in the first 2 years after diagnostics of BEN. Because of an ambiguity of an etiopatogenez prevention is complicated. As the possible measures preventing development of an uropatologiya earlier resettlement of inhabitants of the endemic centers on other territories, an exception of closely related marriages of representatives of families at which the Balkan nephropathy came to light is offered. Improvement of an ecological situation can play a possible positive role: qualitative filtration of water, fight against a lomonosovidny birthwort, fungal defeat of grain crops, control of impurity of food ochratoxin A. Secondary prevention is directed to screening urological control of the contingents from risk group.