Nephrotic syndrome in children

Nephrotic syndrome is a symptomatic complex, including pronounced proteinuria (more than 3 g / L), hypoproteinemia, hypoalbuminemia and disproteinemia, marked and common edema (peripheral, cavitary, anasarca), hyperlipidemia and lipiduria.

Nephrotic syndrome in children is divided into primary, associated with the primary disease of the actual glomeruli of the kidneys and secondary, caused by a large group of congenital hereditary and acquired diseases.

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Pathogenesis of nephrotic syndrome

In the occurrence of water-electrolyte disorders, the development of edema in nephrotic syndrome, the importance of the renin-angiotensin-aldosterone system, antidiuretic, as well as natriuretic hormones, kallikrein-kinin and prostaglandin systems is attached. Loss in the urine of many proteins leads to changes in coagulation and in fibrinolysis. In nephrotic syndrome, there is a deficit of anticoagulants (nitrombin III - plasma cofactor of heparin); disorders in the fibrinolytic system - the content of fibrinogen increases. All this contributes to hypercoagulation and thrombosis. Especially dangerous is thrombosis of the renal veins. Thus, nephrotic syndrome is accompanied by a number of changes in homeostasis.

In the genesis of nephrotic edema, the role of the atrial natriuretic peptide (ANP) is also considered. Violation of the normal effect of ANP on transport processes in the collecting ducts of the kidney canals is accompanied by a decrease in natriuresis and the accumulation of intravascular fluid, which contributes to the formation of nephrotic edema. Thus, nephrotic syndrome is accompanied by a number of changes in homeostasis.

In the nephrotic syndrome, the membrane and membranous-proliferative glomerulonephritis, more rarely the focal-segmental glomerulosclerosis, are most often noted.

Nephrotic syndrome primary:

• Congenital and infantile:
  • congenital "Finnish type" with microcystosis;
  • "French type" with diffuse mesangial changes;
  • nephrotic syndrome with minimal changes;
  • nephrotic syndrome with mesangioproliferative changes or with focal-segmental glomerulosclerosis.
• Nephrotic syndrome in primary glomerulonephritis:
  • Nephrotic syndrome with minimal changes;
  • Nephrotic syndrome with membranous changes or focal-segmental glomerulosclerosis; membranous-proliferative, mesangioproliferative, extracapillary with semilunium, fibroplastic (sclerosing) changes.

Nephrotic syndrome is secondary, with hereditary, congenital and acquired diseases:

• diffuse connective tissue diseases (systemic lupus erythematosus);
• systemic vasculitis;
• infectious diseases (tuberculosis, syphilis, hepatitis, malaria);
• diabetes;
• reactions to medications (antiepileptics, preparations of gold, bismuth, mercury, antibiotics, vitamins);
• thrombosis of the renal veins.

Nephrotic syndrome can manifest as complete and incomplete, pure and mixed (with hematuria and arterial hypertension) symptom complex.

The primary nephrotic syndrome is congenital and nephrotic syndrome in primary glomerulonephritis.

Morphological variants of primary nephrotic syndrome with glomerulonephritis: minimal changes, membranous, focal-segmental, mesangiocapillary (membranous-proliferative), extracapillary with semilunium, fibroplastic.

In the structure of primary nephrotic syndrome, glomerulonephritis with minimal changes predominates in children aged 1-7 years (more than 85-90%), the so-called lipoid nephrosis.

In children aged 12-16 years in the structure of primary glomerulonephritis, membrane-proliferative glomerulonephritis (of all 3 types) is predominant, manifested more often in a mixed nephrotic syndrome with hematuria and / or hypertension, which has a serious prognosis.

Nephrotic syndrome

Nephrotic syndrome is one of the most pronounced and characteristic manifestations of acute and chronic kidney disease in children. The presence of a nephrotic syndrome always indicates the damage to the kidneys, primarily or in the context of other diseases. The appearance of nephrotic syndrome in kidney diseases testifies to the increased activity of the kidney process.

Symptoms of nephrotic syndrome

Characterized by edema - first face, eyelids, then - in the lumbar region, legs. Pale skin. Oliguria associated with hypovolemia, hyperaldosteronism, tubular damage.

Secondary hyperaldosteronism is typical for nephrotic syndrome, as a result, sodium is retained in the body, and consequently water, although there is hyponatremia in the blood.

In children, hypovolemia often develops spontaneously, in the initial stage of the nephrotic syndrome, when the rate of protein loss exceeds the rate of protein mobilization from extravascular depots, its synthesis by the liver.

The course of nephrotic syndrome

Often wavy, recurrent. Recurrent nephrotic syndrome - occurrence of at least 2 relapses in bess; often recurrent course - 2 or more relapses in besses or 4 or more in a year, when the relapse occurred within 2 months after discontinuation of therapy. Full remission is understood as a patient's condition when proteinuria is less than 4 mg / m ² / hour or less than 10 mg / kg / h, and the serum albumin level is equal to or more than 35 g / l. Partial remission means elimination of edema, hypo- and dysproteinemia, a decrease in daily proteinuria to less than 3.5 g / day or its maintenance in the range of 5-40 mg / m ² / h and albumin of blood serum more than 30 g / l.

Treatment of nephrotic syndrome

The regime during bed swelling can lead to an increase in diuresis, since in the horizontal position the hydrostatic pressure on the lower extremities decreases, which facilitates the return of fluid from the interstitial space to the plasma. Access to fresh air.

The diet is salt - free 2-3 weeks with the subsequent gradual introduction from 0.5-1 g to 3 g per day. Hypochloride diet remains for many years. Proteins of high biological value of 1 g / kg of body weight, taking into account the daily protein loss. The fat content, which gives less than 30% of the total caloric content of food with a high polyunsaturated / saturated fatty acid ratio, contains linoleic acid in an amount that provides at least 10% of the total caloric content of food and low cholesterol.

It is recommended to use sea fish, shrimp, sea kale, which increase the fibrinolytic activity of the blood. Use of vegetable oil. It is advisable to include in the diet of oats rich in phospholipids, in the form of porridge, jelly, broth. During the convergence of edema, products containing potassium are introduced: baked potatoes, raisins, dried apricots, prunes, bananas, pumpkin, zucchini. The liquid is not limited. Elimination diet is prescribed for children with a history of allergic anamnesis.

Drug treatment of nephrotic syndrome

With minimal changes, treatment with glucocorticoids is prescribed. The initial dose of prednisolone is 2 mg / kg / day (not more than 60-80 mg) for 4 weeks daily. A decrease in the maximum dose is made provided there is no proteinuria in 3 consecutive urine tests. The dose is reduced by 2.5-5 mg every week. Then intermittent therapy is carried out - 3 days in a row, a break of 4 days or a day later. The duration of the first course is from 2 months to 2 years (maintenance dose is usually 10-15 mg / day). If successful treatment remains monotherapy with prednisolone. When HC recurring often to hormonal therapy, cytostatics-cyclophosphamide or methylprednisolone (3 days of pulse-therapy 20 mg / kg / day intravenously and followed by prednisolone every other day for 6 months) are added to the hormonal therapy. With hormone-resistant nephrotic syndrome - the lack of normalization of urine indicators and the onset of clinical and laboratory remission in the treatment of glucocorticosteroids for 4-8 weeks - appoint glucocorticosteroids and cyclophosphamide 1.5-2 mg / kg to 16 weeks.

Indications for heparin in the risk of thrombotic complications:

1. hypoalbuminemia below 20-15 g / l;
2. hyperfibrinogenemia above 5 g / l;
3. reduction of antithrombin III up to 70%.

With hypoalbuminemia below 15 g / l for the prevention of hypovolemic crisis, intravenous dropping of rheopolyglucin with subsequent jetting of lasix 1 mg / kg (or without it) is indicated.

With hypoalbuminemia below 15 g / l for the prevention of thrombotic complications, the choice drugs may be curantyl at a dose of 3-4 mg / kg / day or a tiklide of 8 mg / kg / day. For the purpose of correcting hyperlipidemia and lipiduria, a food supplement of eikonol is prescribed, as well as preparations blocking the synthesis of cholesterol and low-density lipoproteins - lipostabil, lovastatin. In order to stabilize cell membranes, use alpha-tocopherol, Essentiale forte, Dimefosfon. To prevent and treat osteopenia and osteoporosis use calcium carbonate, calcium gluconate. With ARVI - reaferon, interferon.

Clinical follow-up is performed by a pediatrician and nephrologist before the transfer of the child to an adult polyclinic. After discharge from the hospital, a urinalysis in the first 3 months is performed once every 2 weeks, then during the first year of observation - once a month, in the second year and subsequent years, once a quarter. At each visit of the doctor, blood pressure is measured, treatment correction and observation are performed. With intercurrent diseases, it is mandatory to study urine during the illness and 10-14 days after the end of it, consultation of ENT doctor and dentist is carried out once every 6 months. It is necessary to sanitize chronic foci of infection.

The prognosis depends on the morphology of glomerulonephritis. With minimal changes - more favorable, with other forms the prognosis should be cautious, with focal-segmental sclerosis - unfavorable, the development of chronic renal failure.

[5], [6], [7], [8], [9], [10]