Thiamn-biotin dependent basal ganglia disease is a rare inherited disorder. The earliest possible diagnosis plays a crucial role in prevention of death or brain damage due to the severity of the disease. Neonatal screening is not adequate because of the extreme rarity of this disease. The demonstrated familial record showcases the need for selective screening in cases of a burdened familial anamneses in patients with undifferentiated encephalitic crises, including undifferentiated mitochondrial encephalopathies, and confirms the importance of the earliest possible start of metabolic therapy with thiamine and biotin in order to reaching the satisfactory compliance from the family. The severe importance of regular dispensary observation and testing coupled with the timely correction of treatment in such patients is shown as well.

Background. There are limited data on the efficacy of long-term enzyme replacement therapy (ERT) in children with mucopolysaccharidosis (MPS).Objective. Our aim was to study the efficacy and safety of long-term ERT in children with MPS type I, II, and VI.Methods. We analyzed the results of ERT with laronidase, idursulfase, and galsulfase in children with MPS type I, II, and VI admitted to the federal research center from January 2007 to November 2016. The response rate was assessed by the level of normalized urinary excretion of glycosaminoglycans (GAGs) (the ratio of GAGs concentration to urine creatinine) recalculated in percent (%) exceedance of the upper limit of normal for the corresponding age. Data on the administered therapy and its results, including adverse events, is extracted from the medical records of in-patients.Results. The results of treatment (intravenous infusions, intervals between administrations from 4 to 10 days) were studied in 33 children (5 of them were girls) with MPS type I (n = 4; laronidase at a dose of 0.58 mg/kg), II (n = 26; idursulfase at a dose of 0.5 mg/kg), and VI (n = 3; galsulfase at a dose of 1 mg/kg). A decrease in the normalized urinary excretion of GAGs from 376% (172; 791) to 54% (0; 146) exceedance of the upper limit of normal for the age (p < 0.001) was noted in the course of ERT lasting (median) 27 (14; 41) months. A decrease in the normalized GAGs excretion below the upper limit of normal for the age was established in 12/33 (36%) patients. ERT-associated adverse events were identified in 12 patients; one case required a two-fold therapy interruption. The development of nephrotic syndrome in the course of ERT in patients with severe MPS II was first described.Conclusion. Long-term ERT in children with MPS type I, II, and VI is characterized by acceptable efficacy and safety. Key words: children, mucopolysaccharidosis, enzyme replacement therapy, laronidase, idursulfase, galsulfase, glycosaminoglycans.

Joint pathology without signs of inflammation must always arouse suspicion of lysosomal storage diseases, mucopolysaccharidosis (MPS) in particular. It is these orthopedic diseases in mild MPS type I, which are an early sign of the disease; moreover, somatic disorders may be absent or present slightly. Joint contractures are currently chosen as the starting point of an algorithm, a developed diagnostic algorithm for the examination of patients with MPS type I, which is also applicable to the early diagnosis of all forms of mild MPS.

Sanfilippo syndrome (mucopolysaccharidosis type III) is a lysosomal disorder caused by a defect in the catabolism of heparan sulfate. Mucopolysaccharidosis type III is the most common type of all mucopolysaccharidoses. The pathogenic basis of the disease consists of the storage of undegraded substrate in the central nervous system. Progressive cognitive decline resulting in dementia and behavioural abnormalities are the main clinical characteristics of Sanfilippo syndrome. Mucopolysaccharidosis type III may be misdiagnosed as otherforms of developmental delay, attention deficit/hyperactivity disorder and autistic spectrum disorders because of lack of somatic symptoms, presence of mild and atypical forms of the disease. Patients with Sanfilippo syndrome may have comparatively low urinary glycosaminoglycans levels resulting in false negative urinary assay. Definitive diagnosis is made by enzyme assay on leucocytes and cultured fibroblasts. There is currently no effective treatment of mucopolysaccharidosis type III, though ongoing researches of gene, substrate reduction and intrathecal enzyme replacement therapies expect getting curative method to alter devasting damage of central nervous system in near future.

Mucopolysaccharidoses are a group of hereditary metabolic diseases, relating to lysosomal storage disorders and caused by a deficiencyof the enzymes, involved in degradation of glycosaminoglycans (mucopolysaccharides). Severe forms of mucopolysaccharidoses of types I, II and VII and mucopolysaccharidosis of type III are characterised by primary central nervous system damage and neurodegenerative course of the disease with cognitive decline, behavioural abnormalities and decreased lifespan. Neuropathogenesis of mucopolysaccharidoses is not completely studied. The question of reversibility of cellular damage is still open. There is currently no effective treatment for mucopolysaccharidoses with primary central nervous system damage. Intravenous enzyme replacement therapy doesn’t cross the blood-brain barrier and has no influence on neurodegeneration. Investigation of alternative treatment options, providing delivery of therapeutic agent to central nervous system, is currently being carried out. Preclinical studies of highdose, intrathecal, intraventricular enzyme replacement therapy; administration of modified enzyme, capable of crossing the blood-brain barrier; gene, cell therapies, stop codon readthrough approach and substrate reduction therapy show promising results.

The article presents an analysis of outpatient specialized neurological care appeals to the consultative-diagnostic center and the neurological pathology structure, as well as age and gender peculiarities of its breakdown. The authors revealed that higher mental dysfunctions are the most widespread. They also provide an analysis of underestimation of separate neurological deviations by parents. The article provides recommendations on outpatient specialized pediatric neurological care delivery optimization.

The article presents an analysis of outpatient specialized neurological care appeals to the consultative-diagnostic center and the neurological pathology structure, as well as age and gender peculiarities of its breakdown. The authors revealed that higher mental dysfunctions are the most widespread. They also provide an analysis of underestimation of separate neurological deviations by parents. The article provides recommendations on outpatient specialized pediatric neurological care delivery optimization. Keywords: children, outpatient neurological care, pediatric neurological appeal incidence structure, cognitive disorders, speech disorders.