The main epidemiological indicators of tuberculosis were studied in children and adolescents in Russia over the past two decades, the work done in groups at risk for the disease was characterized, and its efficiency was analyzed. The results of introducing a procedure to detect tuberculosis in children were summarized using innovative technologies both in the antituberculosis service and during screening of the pediatric population older than 8 years of age.

The author defined new problems in phthisiopediatrics with the advent of multidrug resistance of Mycobacterium tuberculosis, HIV infection in patients with tuberculosis and with the necessity of revising the approaches to preventing it in the risk groups and to treating children with this disease. She showed the importance of the tuberculosis problem and the need for continuing researches of these issues. 

The paper gives data on the impact of assisted reproductive technologies (ART) on the cardiovascular system and metabolism in children and adults conceived by the above technologies. It issuggested that epigenetic exposures may be a main mechanism for programming cardiovascular and metabolic abnormalities in the later life of these children. 

The paper gives information on current mucoactive therapy with carbocysteine for acute and chronic bronchopulmonary diseases. The author’s observations during a multicenter study and the data available in the literature provide evidence that carbocysteine lysine salt (Fluifort) shows high clinical and immunological efficacies as a mucoregulatory and mucolytic agent used in children aged 2 to 17 years with acute and chronic bronchopulmonary diseases. The highest efficacy of carbocysteine lysine salt has been found in schoolchildren, which is attributable to the age-related features of the formation of the bronchial secretory apparatus and local immune system, as well as in the children with protracted and chronic inflammatory processes, including those associated with smoking. 

Examinations were made in 35 boys and 39 girls with extremely low birth weight in order to identify gender-related clinical and immunological features. A comparison group consisted of 31 full-term newborns with early uncomplicated adaptation. The investigators determined the number of lymphocyte subpopulations and cytokine-producing cells (CD3+INF-γ+, CD3+IL-4+) by flow cytometry and the serum levels of cytokines (IL-4, IFN-γ) and neopterin by enzyme immunoassay. A study of immunological parameters revealed that the boys had a smaller number of CD3+, CD4+, and CD8+ subpopulations, a reduced content of CD3+IL-4+ cells at birth, and low IL-4 production on the first day of life compared to the full-term neonates. The girls were recorded to have higher levels of neopterin and B cells on the first day of life, the quantitative characteristics of T lymphocytes were consistent with those in the full-term infants. The findings are indicative of the greater functional immaturity of the immune system in the preterm boys. 

The paper presents common ENT problems in premature infants, which lead to their disability in the future. It is emphasized that premature babies are in a group at risk for deafness and poor hearing. Decreased hearing in an infant under the age of 1 year provokes prespeech and speech developmental delays that complicate his/her social adjustment. The aforesaid determines a more thorough follow-up of the development of auditory function and speech in preterm infants of different gestational ages during the first 3 years of life. 

X-linked intellectual disability (XLID) is a clinically and genetically heterogeneous group of hereditary diseases caused by mutations on the X chromosome, which lead to impaired intellectual development. The paper determines for the first time the proportion of X-linked diseases (6.54%) in the pattern of intellectual disability in children. A system has been developed to quantify the clinical severity of fragile X mental retardation syndrome and Rett syndrome. A system has been scientifically justified to predict the clinical severity, which is based on an analysis of the impact of genetic and epigenetic factors (mutation type and location, X chromosome inactivation). The authors have determined the contribution of nonrandom X inactivation to the clinical polymorphism of various forms of XLID and established its role as an important diagnostic marker for pathology. It is shown that the study of X chromosome inactivation can identify asymptomatic female carriers of X-linked mutations to provide medical genetic counseling to families. An algorithm has been elaborated to diagnose XLID among the undifferentiated forms of mental developmental abnormalities in children. 

The paper considers a clinical case of a child with suspected mitochondrial encephalomyopathy: cyclic vomiting, evident fatigue, muscle weakness, headache, and difficulties in learning school material. The similar symptoms are noted in an older sibling; the mother suffers from type 1 diabetes mellitus. The entire mitochondrial genome was sequenced in the proband. Despite the fact that significantly pathogenetic variants have not been identified, there are a number of individual mitochondrial DNA characteristics that may be of clinical significance. Of particular interest are two variants: m.T8477C and C12562G, which have a sufficiently high pathogenic potential. To establish their role requires further investigations of mitochondrial DNA in the mother and sibling. 

The paper deals with a rare monogenic connective tissue disease from a group of fibrillinopathies with autosomal dominant inheritance — Beals syndrome caused by a mutation in the FBN2 gene. Attention is drawn to the high phenotypic similarity of this disease and Marfan syndrome (FBN1 gene mutation), which is associated with the almost complete identity of two proteins: fibrillin 1 and fibrillin 2.

The paper describes a clinical case of a child with Beals syndrome and the typical manifestations of the disease: asthenic constitution, arachnodactyly of the hands and feet, congenital contractures of the large and small joints, chest deformity, kyphoscoliosis, talpes, and crushed ears. The investigators made a differential diagnosis with other connective tissue diseases, such as Marfan syndrome, Stickler syndrome, Ehlers–Danlos syndrome, homocystenuria, and arthrogryposis. DNA diagnosis verified the Beals syndrome in the proband. Exon 28 in the FBN2 gene showed the previously undescribed missense mutation of c.3719G>A, resulting in the amino acid substitution of cysteine for tyrosine (p.Cys1240Tyr) in the structure of the protein fibrillin 2. A de novo mutation occurred. There is evidence for its pathogenicity in the development of the clinical symptoms of the disease. The problems of effective medical genetic counseling in this family are discussed. 

The degree of respiratory organ injury in cystic fibrosis determines the prognosis of the disease. Objective: to evaluate external respiratory function in children with cystic fibrosis. The study enrolled 48 children followed up at the Omsk Cystic Fibrosis Center. A control group consisted of 42 non-addicted smoking children with no evidence for respiratory diseases in the history. External respiratory function was evaluated using computed bronchophonography; spirography was additionally carried out in children over 6 years of age. Computed bronchophonography revealed obstructive respiratory failure in all children with severe cystic fibrosis. Chronic respiratory tract infection with Pseudomonas aeruginosa and bronchiectasis were associated with the higher values of the acoustic work of breathing at frequencies over 5000 Hz. It was established that there was a moderate negative correlation between the value of the acoustic work of breathing in the high frequency range and the forced expiratory volume in 1 second in %. Conclusion. Computed bronchophonography could reveal obstructive external respiratory dysfunction in children less than 6 years of age. 

This specific clinical example of a female patient with DiGeorge syndrome, a primary immunodeficiency disease, demonstrates difficulties in its timely diagnosis and in the choice of treatment policy in this category of patients. Lung injury in them is frequently the only manifestation of the underlying disease. Special attention is given to current diagnostic criteria (including genetic ones) and approaches to treatment and prognosis in patients with DiGeorge syndrome. 

The high rate of recurrent bronchial obstruction in toddlers and preschoolers is due to both the morphofunctional characteristics of the respiratory tract in these age groups and the high incidence of acute respiratory infections. The diagnosis of asthma presents objective difficulties in children aged less than 5 years. Not all children with recurrent virus-induced obstruction can further develop asthma. Nevertheless, an analysis of a family and personal history of allergy, the clinical manifestations of the disease, and a response to anti-inflammatory therapy, if indicated, can diagnose asthma at any age and use basic therapy in relation to the severity of the disease. 

The paper describes a procedure for examining patients with hypertrophic cardiomyopathy, which is based on the study of myocardial segmental radial deformity in relation to the thickness of the myocardial segment in order to determine the critical myocardial thickness, in which systolic myocardial dysfunction occurs first in the segment. This procedure may be used to identify indications at the beginning of therapy in asymptomatic patients with hypertrophic cardiomyopathy. 

The paper presents the special questionnaire «Quality of Life in Children with Arrhythmias» that reflects the subjective assessment of quality of life (QOL) in patients with cardiac arrhythmias and a procedure for the comprehensive assessment of QOL in children with arrhythmias on the basis of subjective and objective data. It gives the results of using the above procedures for assessing QOL in 151 children (71 girls and 80 boys) aged 6–18 years with various cardiac arrhythmias. Complaints were absent in 21,9±3,4% of the children with arrhythmia and were nonspecific, being rarely observed, in 29,8±3,7%, suggesting that there was no reduction in QOL according to their subjective assessments. Comprehensive assessment of QOL showed that its indicators were significantly lower (p<0,05) than those obtained by subjective assessments. Thus, cardiac arrhythmias accompanied by a varying decrease in QOL were seen in 84,8±2,9% of the children, as shown by its comprehensive assessment and in 48,3±4,1% of the patients, as evidenced by their subjective assessments. Patients with organic heart disease and/or signs of chronic heart failure exhibited a decrease in QOL significantly more often (p<0,001). The leading causes of worse QOL were health changes in 56,3±4,0% of the patients, psychoemotional disorders in 77,5±3,4%, autonomic dysfunction in 81,5±3,2%, reduced adjustment in 82,8±3,1%, and pathological changes in cardiovascular function in 84,1±3,0%, as indicated by ECG, 24-hour ECG monitoring, and Doppler echocardiography.

Objective: to determine the urinary concentrations of cytokines for the diagnosis of the localization of inflammation in the urinary system and to establish the contribution of mediators of the immune system to the pathogenesis of the pathology in question.

Twenty-nine children aged 2.7 to 11.5 years with pyelonephritis (n=16) and the unspecified localization of urinary infection or cystitis (n=13) were examined. A control group consisted of 15 healthy children. Cytokine levels were determined in the morning urine portion using the multiplex xMAP technology and then recalculated to the concentration of creatinine.

Urinary tract infection was accompanied by an avalanche-like increase in the total urinary cytokine concentration, which was 20-fold greater than the reference values in the children with pyelonephritis. Interleukin 8 (IL-8) constituted the highest proportion of cytokines. IL-10 and interferon-γ (IFN-γ) made up the smallest percentage in the total mass of cytokines. Higher IL-6 and IFN-γ values and a simultaneous increase in the level of 2 or more cytokines are of the greatest diagnostic value in determining the renal site of urinary tract infection. 

Objective: to assess the pattern of clinical forms of tuberculosis and concomitant pathology in children in time and age aspects. Four groups of children who had fallen ill with tuberculosis in 1995–1999 (n=149), 2001–2005 (n=429), 2006–2010 (n=385), and 2011–2015 (n=350) were identified. In Groups 1, 2, 3, and 4, isolated respiratory organ injury involved by tuberculosis was found in 96.6. 83.0, 87.6, and 92.6% of cases, respectively (χ2 =28.418; р=0.000). In Groups 1–4, generalized tuberculosis was diagnosed in 2, 5.1, 8.8, 5.1% of children, respectively (χ2 =10.821; р=0.016). Comorbidity was detected in 49.0, 73.2, 88.1, and 80.3%, respectively (χ2 =97.985; р=0.000). Cardiovascular disease was prevalent in children aged 12–14 years (42.1%) (χ2 =27.678; р=0.000). In the time aspect of over 20 years, the children with tuberculosis were twice more frequently found to have comorbidity, which may be related not only to the better quality of diagnosis, but also to decreased health levels in the children. Infants were more vulnerable in the context of comorbidity. 

The key epidemiological indicators were investigated over time forthe bacilli Calmette-Guérin (BCG) (BCG-M) vaccination of HIV-infected children. BCG-induced immunity and vaccination safety were studied in 376 children, including 131 with an established diagnosis of HIV infection, 141 with a perinatal HIV infection contact, and 104 children born to HIV-negative women. There were 60 cases of tuberculosis among the vaccinated. BCG vaccination of children born to HIV-infected women, but to HIV-uninfected ones was ascertained to show a 4-fold decrease in the risk of tuberculosis at an early age and in that of disseminated tuberculosis (including meningitis) (OR= 3.78; p0.05).

BCG vaccination of the HIV-infected children did not reduce the risk of disseminated processes: their proportion among the vaccinated and the unvaccinated was 28.9 and 20.3%, respectively (p>0.05). BCG postvaccination immunity was determined in only one third (29.7%) of the vaccinated in the presence of a small scar in 76.9% of cases. 

The diagnosis and correction of tube disorders remain one of the least resolved and the most difficult problem in otorhinolaryngology. Eustachian tube function was evaluated in 144 children with recurrent otitis media and exudative otitis media after surgical intervention into the nasopharynx. All the children underwent tympanometry and diagnostic endoscopy of the nasal cavity and nasopharynx. Before surgery, types B, C, and A tympanograms were recorded in 146 (50.69%), 97 (33.68%), and 45 (15.62%) cases, respectively. key. One month after surgery, tympanometry readings became normal in 85 (91.39%) children.

Conclusion. The most complete diagnostic information can be obtained during different endoscopic modes in children with tube dysfunctions. Tympanometry is an objective noninvasive method for the assessment of Eustachian tube function and a criterion for the evaluation of the efficiency of the treatment performed. 

The diet of modern nursing women consisting of natural foods is adequate for the consumption of energy and sometimes excessively caloric can not to provide the organism with the necessary amounts of vitamins. The content of vitamins in breast milk of insufficiently supplied women is less than in nursing mothers, adequate supply of vitamins. The needs of the growing breast-fed child by women with multivitamin deficiency can not to satisfied by means breast milk. Based on the analysis of the vitamin status of pregnant and lactating women, as well as the content of vitamins in breast milk of mothers with various vitamins sufficiency conclusion for inclusion in the diet of infants enriched with vitamins and minerals weaning cereal-based products (cereals) had been made. Vitamin and mineral supplements or vitamin enriched foods must be included in the diet to maintain the vitamin status of lactating women. 

The tuberous sclerosis complex genes (TSC1 and TSC2) function as classic tumor suppressor genes in health; a loss of function of these genes results in activation of the kinase m-TOR and to development of benign tumors. Despite their slow progression, renal subependymal giant cell astrocytomas and angiomyolipomas can cause fatal outcomes. Both Phases I–II and III EXIST-1 and EXIST-2 trials demonstrated that the m-TOR inhibitor everolimus had good efficacy and tolerability: the volume of astrocytomas and that of angomyolipomas were reduced by 50% or more in 35 and 41% of patients, respectively. After 3.5 years of the trials, everolimus showed a high retention rate: 80.2 and 79% of the patients, respectively. Virtually all patients were observed to have adverse reactions, most commonly stomatitis, oral ulcers, and nasopharyngitis. Everolimus has been registered in the Russian Federation and Russian patients participated in the EXIST-1 and EXIST-2 trials. The indications for prescribing the drug are tuberous sclerosis complex-associated subependymal giant cell astrocytomas and angomyolipomas in patients older than 3 and in those older than 18 years of age, respectively. Everolimus has the potential for targeted treatment for the spectrum of clinical manifestations of tuberous sclerosis complex. 

The rate of infection with herpes simplex virus is 65–90% in the population. The virus persists in the body for life and causes a wide spectrum of clinical manifestations in disease recurrences and reduces quality of life. This article deals with an analysis of the efficiency of topical therapy for recurrent orofacial herpes infection in childhood. A randomized study covering 40 patients aged 6 to 12 years was conducted with a 12-month follow-up. The efficacy of the classical antiviral medication Zovirax and the complex topical agent Herpenox was compared. According to the results, both drugs reduce the severity of subjective symptoms of the disease in the patients, but do not completely prevent recurrent rashes. The patients treated with the complex drug Herpenox recovered on days 7–8, by reducing the duration of the vesicular stage and by accelerating of lesion epithelialization. The test drugs failed to affect the incidence of subsequent recurrences. 

Objective: to determine the efficiency of antenatal prevention of food allergy in children. A total of 248 mother-child pairs were followed up. According to their maternal feeding pattern during pregnancy, the newborn infants were divided into 3 subgroups. Subgroup 1 consisted of 37 infants whose mothers had ingested a hypoallergenic diet during pregnancy. Subgroup 2 entered 29 babies, whose mothers had adhered to a hypoallergenic diet and received the probiotic Lactobacillus reuteri Protectis in the last stages of gestation. Subgroup 3 comprised 82 infants whose mothers had received a diet with a hypoallergenic substitute of cow’s milk for the New Zealand goat’s milk Amalthea in combination with the probiotic during pregnancy.

There were no differences between the neonatal groups in anthropometric indicators. Analysis of intestinal microbiota showed that significantly more children had an increasing amount of Klebsiella, enterococci, Candida albicans, and Staphylococcus aureus in the comparison group (p<0.05). Subgroup 3 babies whose mother had received lactobacilli and the whole goat’s milk Amalthea were more frequently found to have normal levels of bifidobacteria and lactobacilli (p<0.05) and a smaller number of opportunistic pathogens (p<0.05) in the enteric flora. In addition, the hypoallergenic diet including goat’s milk and/or Lactobacillus reuteri Protectis in mothers in the last stages of gestation reduced the frequency and degree of sensitization to cow’s and goat’s milk in the infants.

13th Russian conference on Pediatrics and pediatric surgery in the Volga federal district.

The article presents modern data on etiology, epidemiology, clinical manifestations of infection caused by the herpes simplex viruses type 6. The problems ofthe use oflaboratory methods of research and treatment ofinfections. 

The paper gives the results of following up 88 children aged 8.5 months to 17 years who were treated at the Republican Clinical Infectious Diseases Hospital in Kazan in 2015–2016 for a diagnosis of infectious mononucleosis. It considers its clinical manifestations in relation to the etiology of the disease and hospitalization outcomes. Main laboratory changes are assessed. 

Aim — determine the clinical and laboratory features of acute intestinal infection in children, occurring in conjunction with atopic dermatitis (AD).

Material and methods. We conducted a study of «case-control», which included observation of 144 children hospitalized in the infectious hospital with a clinic of acute infectious diarrhea in the period from January to December 2012. In the study group were selected 72 children with atopic dermatitis clinic and acute infectious diarrhea in a couple of which, from the group of patients without burdened premorbid background were selected 72 «controls» matched by sex, age and etiology developed acute intestinal infection. The observation time was 5±2 days, which corresponds to the average length of stay of the child, patients with moderate forms of acute intestinal infection in the hospital.

Results and discussion. About 2 times more often than in the control, acute intestinal infections in children with atopic dermatitis lesions were characterized by clinic middle and lower gastrointestinal — 31.9% (CI 21,1–42,7) vs. 15.3% (CI 7–23 6), p=0.03. A number of bowel movements 6 or more times per day significantly more frequently observed in children with a combination of acute intestinal infections and atopic dermatitis — 54.1% (CI 42,6–65,6) vs. 33.3% (CI 22,4–43.9) in the control), p=0.011. The duration of diarrhea was higher in the study group (Med 6 IQR 4–7 days and Med 5 IQR 3–6 days, respectively), p=0.046. The proportion of patients with high fever was also higher in the study group than in the controls –15.3% (CI 7–23,6) vs. 2,8% (CI 1–6,6), p=0.016.

Conclusion. Acute intestinal infections in children with atopic dermatitis have a more pronounced clinical symptoms, which is characterized by clinic enterocolitis, severity and duration of diarrhea syndrome, usually accompanied by a high fever. 

The interest of the doctors — pediatricians to recurrent bronchitis is caused by its high specific weight in the structure of bronchopulmonary pathology in children, the complexity and the need to search the differential selection of an individual regimen and prevention. Recurrent bronchitis with bronchoobstructive syndromes patient is regarded as a predictor of asthma, however, erroneously consider these nosological forms as the stages of a single pathophysiological chain as congenital and acquired diseases of respiratory system, pathology of gastro-intestinal tract, cardio-vascular system can masquerade as recurrent bronchitis. The aim of this work — to analyze the current medical literature on the problem of differential search causes leading recurrent respiratory syndrome in children. Materials and methods. The review publications domestic and foreign authors studied data from clinical and epidemiological studies. Results and its discussion. Anatomical physiological characteristics of the respiratory tract, complicated premorbid background, the re-infection of the child respiratory infection contribute to the recurrent course of bronchitis. The most common recurrent bronchitis is transient, recurrent bronchitis episodes completely stoped with the age of the child. Recurrent respiratory infections can fix bronchial hyperreactivity and with the presence of aggravated allergic history lead to the development of asthma. Severe bronchitis, resistance to standard scheme of therapy, the frequent recurrence of respiratory syndrome dictate the need to expand the diagnostic research to clarify the leading cause of recurrent bronchitis. Conclusion. Recurrent bronchitis is considered as a separate nosological form. At the same time, by repeated episodes of respiratory infection may be masked by malformations, hereditary diseases of respiratory system, bronchus foreign body microaspiration syndrome, pathology of the cardio-vascular system. 

The paper deals with portopulmonary hypertension (pulmonary arterial hypertension associated with portal hypertension). Pulmonary hypertension is a rare, prognostically unfavorable complication of portal hypertension, regardless of the etiological factor of the latter. The diagnostic criteria for portopulmonary hypertension are portal hypertension with or without liver disease; a resting mean pulmonary artery pressure >25 mm Hg; a normal pulmonary artery wedge pressure <15 mm Hg; and a pulmonary vascular resistance of more than 3 Wood units/m2. Objective: to describe of the development of the clinical picture, diagnosis, and treatment of portopulmonary hypertension in a patient during corrected portal hypertension. There are challenges in the diagnosis of portopulmonary hypertension because its symptoms are nonspecific. The most characteristic symptoms of the disease are dyspnea, fatigue, exercise intolerance, and syncope.

Hepatopulmonary syndrome (HPS) is a rare complication of liver diseases, resulting in lung perfusion disturbances and reduction of blood oxygenation. We report a case of hepatopulmonary syndrome in an 11- year-old-boy with congenital liver fibrosis. 

The article presents the results of a examination of 105 children aged 1 to 16 years, 22 of them are diagnosed with nephrocalcinosis, 11 stone in the urinary system amid hypercalciuria, 23 hypercalciuria was observed without the formation of concretions in the urinary system, 49 children with chronic pyelonephritis. In children with hypercalciuria, nephrolithiasis and nephrocalcinosis decreased bone mineral density was observed in 45% of cases, in children with chronic pyelonephritis osteopenia was found in half of the patients (51%). Reduced bone mineral density in children with hypercalciuria increased risk of fractures. In patients with osteopenia two-and three-multiples fractures were observed in 3 times more than the comparison group. Increase both of alkaline phosphatase and acidic phosphatase showed activation of bone metabolism, and proportionality of their activation determined state of bone mineral density. Patients with chronic pyelonephritis with severe osteopenia observed prepotency of processes of bone resorption relative to bone formation. 

A premature baby needing resuscitation after birth, is exposed to damaging factors affecting the entire body, including the kidneys. Aim — analysis of current data on the issue of the formation of kidney function in children born prematurely. Materials and methods. The review publications domestic and foreign authors studied data from randomized clinical and epidemiological studies. Results and discussion. Events intensive care, which include mechanical ventilation, infusion therapy, parenteral nutrition, intravenous drugs, lead to an increased load on the immature kidney premature baby in the neonatal period. A special risk factor for preterm is still imperfect glomerular and tubular function, renal large capillary surface, high renal blood flow, inadequate regulation of acid-base balance and the ability to concentrate, are under the influence of external loads become insolvent. Under the influence of damaging factors on the kidney nephron deficit increases the risk of further decline in kidney function. It is assumed that no additional nephrons deficit is not negative factors leads to chronic diseases in the future. Conclusion. Analyzing conducted research on the formation of kidney function in children born prematurely, it can be assumed that children with a gestational age less than 32 weeks and weighing less than 1500 grams at birth, who are exposed to adverse environmental factors on the developing buds in the perinatal and neonatal periods. They are in the zone of risk of chronic disease of the kidneys in later life. 

The article provides information on fetal alcohol syndrome (FAS) and the abstinence syndrome in newborns. The data monitoring developmental disorders in 18 children exposed to prenatal influence of alcohol. Described suggested approaches to treatment and management of children with FAS and helping families. It is shown that this problem is poorly studied in Russia and is highly relevant, socially significant and requires further study. 

Rett Syndrome is one of the most socially significant neuropsychiatric hereditary diseases in children. This syndrome is mainly found in girls: its frequency is 1:10000–15000. Currently mutations in X-linked gene MESR2 considered as the main cause of the syndrome. Diagnosis of typical and atypical variants of the syndrome is based on the use of clinical criteria, determining gene mutations МЕСР2, CDKL5 and FOXG1. In 2010, the Expert Consortium for Rett syndrome have revised the existing diagnostic criteria for the syndrome and come to a new consensus. If there is a regression of mental development for the diagnosis of Rett syndrome exemplary embodiment only four basic criteria for the diagnosis of atypical variant — two of the four main criteria, and five of the eleven additional criteria. 

The study of the blood levels of amino acids and carnitine will be able to predict the performance efficiency of young athletes. Objective: to determine blood amino acid concentrations in young athletes and to establish whether they are correlated with the level of carnitine. The study group included 94 athletes with different types of physical activity, as well as children from the control group. The study was conducted by liquid chromatography-tandem mass spectrometry after capillary blood sampling. An analysis of the obtained samples determined the levels of 12 amino acids and identified differences in relation to the type of exercise and gender. The contribution of two amino acids to the variance of the level of bound carnitine was estimated. The contribution of the levels of methionine and phenylalanine was 51.1 and 47.8%, respectively. Thus, the study of the content of amino acids, the level of carnitine, and their relationship can predict the performance efficiency of young athletes, which is especially important to prevent their worse health and lower performance.