There has been significant increase in mental disorders prevalence in pediatric population around the world. Increasing incidence of autism, intellectual incapacity, hyperkinetic disorders, and schizophrenia gives causes for specific concern. Clarifying mental disorders’ etiology and pathogenesis is the priority of researchers. The role of systemic inflammation in psychiatric disorders development currently remains the least studied. However, it can already be stated that generalized peripheral inflammation is the important factor associated with the development of mental disorders both in adults and children. This review presents latest data, as well as an authors’ assessment of systemic inflammation role in the most common mental disorders development in children. Comparative analysis of acute and chronic systemic inflammation manifestations has been performed. The major pathogenetic mechanisms of “systemic damage” in mental disorders have been identified.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is primary electrical heart disease characterized by development of polymorphic, including bidirectional, ventricular tachycardia in response to adrenergic stimulation caused by physical or emotional stress. The major CPVT’s clinical manifestation is faintness caused by exercises, emotional stress, or beta-adrenergic agonists administration. This disease has high mortality rate without any treatment. The difficulties of preclinical diagnosis as well as late diagnosis after CPVT’s clinical signs manifestation dictate the need to analyze and systematize all the data on disease’s causes, clinical manifestations, and existing diagnostic approaches. This work has particular focus on the analysis of the disease molecular genetic causes and the spectrum of associated disorders in patients with CPVT regarding its diagnosis, management, and prognosis. Future research topics were determined for improving diagnosis quality and reducing mortality of patients with CPVT.

The article presents literature review about arrhythmias in children with acute respiratory viral infections (ARVI). The search was carried out in such databases as PubMed, CyberLeninka, RSCI, etc. ARVI is the most common infectious disease in children and adults, and it can have severe course and various complications. Arrhythmias can be frequently revealed in children with ARVI, and most of them are transient. Life-threatening cardiac rhythm and conduction disorders (CRCD) may occur more rarely, especially in severe cases. Knowledge and interest in the pathophysiology of viral infections have increased significantly, including CRCD risk factors in ARVI, thanks to the data obtained during the analysis of COVID-19 clinical course and outcome. This review summarizes and analyzes data on CRCD prevalence and arrhythmogenesis causes in ARVI.

Background. Congenital duplication of small intestine is a complex disease in terms of early diagnosis due to the absence of specific clinical manifestations. Screening methods do not always help to reveal the lesion localization. Only special methods, such as contrastenhanced fluoroscopy, computed and magnetic resonance imaging, allow us to diagnosis gastrointestinal tract (GIT) malformation more precisely. Moreover, the lack of sufficient awareness about this pathology among primary care physicians also postpones diagnosis and, therefore, the timely correction of this congenital GIT malformation. Thus, our clinical case should help primary care physicians to increase alertness on congenital bowel anomaly. Clinical case description. This clinical case demonstrates that intestinal abnormality was suspected in utero at the first trimester of pregnancy according to ultrasound examination. Intestinal colics can be considered as the first clinical non-specific manifestation of congenital anomaly of small intestine in a child under the age of 1 year. Constipation, abdominal pain, and occasional pyretic fever were observed from the age of 2. Intestinal ultrasound has revealed changes, and radiological and magnetic resonance methods confirmed the presence of small intestine malformation. Conclusion. Screening ultrasound of an intrauterine child in the first trimester of pregnancy could force pediatricians to search congenital GIT anomalies despite its non-specific clinical signs. Imaging methods revealed the defect localization, while surgical intervention recovered it. It has prevented any possible complications and improved the patient’s quality of life.

Background. Antiphospholipid syndrome develops at autoimmune diseases, pregnancy, or genetic predisposition, and it is characterized by high risk of thrombosis in arterial, venous, and capillary vessels. This syndrome in children is rare, and necrotic skin lesions occur in the most extreme cases. Clinical case description. A child, 1 year old, with chicken pox has developed hemorrhagic rash on his back, swelling of the left shoulder and forearm on the 4th day of the disease. Medical treatment included acyclovir, ceftriaxone, sodium heparin. Aggravation of hemorrhagic rash over the body, spread of edema from the left shoulder to upper arm and neck, formation of flaccid bubble and necrosis locus (75 cm) on the outer upper third of the left shoulder were noted on the 5th-6th day. Increase in the levels of antibodies to 2-glycoprotein I (IgG — 48.9 U/ml, IgM — > 100 U/ml) and cardiolipin (IgM — 73.0 U/ml) was revealed. The diagnosis “antiphospholipid syndrome” was established. All necrotized tissues were removed on the 11th day, and the wound defect (86 cm) was subsequently covered by mesh skin grafts. The levels of antibodies (IgG + IgM) to 2-glycoprotein I remained high, 45.2 U/mL, 12 weeks after the onset of the disease. Thus, it has confirmed the development of antiphospholipid syndrome. The child continued treatment with warfarin (3.75 mg/day) with INR control. Conclusion. Hemorrhagic skin lesions in children with infectious diseases requires laboratory diagnostics of antiphospholipid syndrome, early prescription of anticoagulant and antiplatelet therapy, and surgical support.

Background. Mucopolysaccharidosis type I (MPS I) is an inherited disease caused by pathogenic variants in the IDUA gene, which encodes the lysosomal enzyme alpha-L-iduronidase. This clinical case demonstrates the importance of diagnosing rare diseases when patients have phenotypic features indicating hereditary pathology presence. Phenotype changes can be so-called “red flag” that helps specialists suspect and diagnose lysosomal storage diseases. Clinical case description. The patient was observed with delayed psychomotor development; she also had hepatomegaly and on auscultation of the heart there was a functional systolic murmur above the apex and in the Botkin–Erb point on heart auscultation. Coarse “garholoid” facial features attracted attention at external examination: large nose, wide sunken nose bridge, macroglossia, thick lips, synophrysis, scaphocephaly, wide chest, and flat-valgus feet. Echocardiography has revealed mitral valve insufficiency and hardened valve leaflets. Ophthalmologist examination: hypermetropic astigmatism. Psychiatrist examination: mental and speech development delay. Enzymatic diagnostics: significant decrease in alpha-Liduronidase activity. No further examinations were carried out due to the onset of the COVID-19 epidemic and parents' doubts about the diagnosis. The patient was readmitted to the hospital at the age of 6 years due to aggravation of her condition. A molecular genetic study has revealed two pathogenic variants in the IDUA gene. Diagnosis of MPS I was established according to the clinical data, results of biochemical and molecular genetic studies. Conclusion. This clinical case demonstrates the classic course of MPS I with typical phenotypic signs and lesions in various organs and systems. The presented case demonstrates the importance of professional vigilance among doctors of various specialties regarding orphan diseases.

Background. GM2 gangliosidosis (Tay-Sachs disease, variant B, type I) is an orphan disease with autosomal recessive inheritance. It develops due to gangliosides accumulation in tissues and organs. The description of clinical case of GM2 gangliosidosis in the patient originating from the Buryat nationality has been presented for the first time. Clinical case description. Girl, 1 year 4 months old, parents — Buryats. There were the following complaints at their admission to the neurology department: lack of movement in the limbs, the child has stopped turning over, became lethargic, slowly ate supplemental feeding. Biochemical blood test has shown increased aspartate aminotransferase activity by 6 times from normal upper limit. α-galactosidase, α-glucosidase, β-D-glucosidase, sphingomyelinase, galactocerebrosidase, and α-iduronidase activities were within the reference levels. Sanger sequencing has revealed the nucleotide variant chr15:72346680G>A (GRCh38) in homozygous state in the HEXA gene. The diagnosis has been established: “GM2 gangliosidosis, type I, infantile form”. Conclusion. GM2 gangliosidosis is a rare disease, especially among Asian populations. Moreover, GM2 gangliosidosis is inherited in autosomal recessive way, thus, two children in the described family had the disease (the first child was assumed to have the disease according to the clinical signs)

Background. Myopia is a serious medical and social problem specifically due to the high risk of such complications as cataracts, myopic maculopathy, glaucoma, and retinal detachment. Children with connective tissue dysplasia (CTD) syndrome are most subjected to myopia. Prevention of myopia progression in children remains the only effective way to prevent myopic maculopathy. Significant progress in this field has been achieved via optical technologies developed on the basis of peripheral defocus theory. Clinical case description. Patient, 10 years old, with CTD, mild myopia of both eyes with rapid progression, myopic maculopathy, grade 1. Ophthalmic status: spheroequivalent refraction — right eye (–)1.5 diopters / left eye (–)1.75 diopters; vision acuity with monocular correction — 1.0. Fundoscopy: optic disc is pale pink, with clear borders, arteries and veins are well-proportioned, their courses and calibers are intact; choriocapillary layer attenuation in the macular and paramacular zones, “parquet fundus”; areas of pigment redistribution on peripheral retina; no atrophic foci detected; anterior-posterior axis of the right and left eyes — 26.2 and 26.3 mm, respectively. Optical coherence tomography (OCT) has revealed retinal thinning in the upper and nasal sectors in the right eye during the first assessment. The left eye has demonstrated losses of retinal thickness within the middle parafoveal zone and significant thinning in the upper segment. Optical therapy with HAL spectacle lenses (inducing volumetric myopic peripheral defocus) was assigned to control myopia to slow down the pathological axial growth of the child's eyes and to stabilize refraction. 4 months of wearing glasses with HAL lenses has led to the stabilization of dystrophic changes in retina, signs of improvement in several sectors by were observed on OCT. No negative changes were revealed in all parafoveal segments of the left eye. The child was recommended to continue wearing glasses with HAL lenses with dynamic follow-up every 3 months. Conclusion. CTD in children is associated with high risk of complications in case of myopia progression, moreover, retinal pathology can occur even with mild myopia. Optical therapy with HAL spectacle lenses is effective and safe first treatment of choice in the control of myopia in children with CTD, and opens new opportunities in prevention of progressive myopia disabling complications in children, whose treatment results were not previously sufficient.

Background. Alopecia areata is an autoimmune disease characterized by hair loss that develops with the involvement of CD8+ T-cells of the immune system and cytokines produced by T-helper 2 cells (Th2). Efficacy of alopecia areata management is limited. The one potentially effective variant for treatment of severe forms of alopecia areata complicated with atopic dermatitis (AD) is genetically engineered biologic drug dupilumab (interleukin 4 receptor antagonist that suppresses Th2 response). Clinical case description. 11 years old boy was admitted to the dermatology department with complaints on aggravation of AD and numerous hair loss foci. Dupilumab, 300 mg, was prescribed once every 4 weeks. Severity of erythematous papular rashes significantly decreased within 9 months, as well as irritation intensity. Complete restoration of hair growth was noted in areas of former alopecia areata foci. Conclusion. Dupilumab can be effective in the management of severe forms of alopecia areata in children with comorbid AD. Clinical studies on the efficacy and safety of such therapy are needed to confirm this hypothesis.

Mucopolysaccharidosis type II (Hunter syndrome, MPS II) is a rare hereditary disease from the group of hereditary metabolic diseases. There are neuropathic and non-neuropathic forms of this disease. The neuropathic form is most common and leads to severe cognitive impairment and progressive damage of central nervous system. Nowadays, early diagnosis and timely initiation of pathogenetic therapy in patients with orphan diseases is the crucial problem of modern pediatrics. Intracerebroventricular administration of idursulfase beta is one of the promising treatment options in patients with neuropathic form of MPS II as it prevents severe complications development. The study of new pathogenetic therapy methods for rare hereditary diseases will help doctors of pediatric specialties to route patient correctly in timely manner to receive all the necessary treatment.