The precocious puberty is an urgent problem of pediatric endocrinology characterized by clinical and pathogenetic heterogeneity. The appearance of secondary sex characteristics before the age of 8 years in girls and 9 years in boys requires timely diagnosis and the appointment of pathogenetically justified treatment in order to achieve the target indicators of final growth and prevent social deprivation. The developed clinical guidelines are the main working tool of the practitioner. They briefly and structurally present the main information about the epidemiology and modern classification of рrecocious puberty, methods of its diagnosis and treatment based on the principles of evidence-based medicine.

Childhood obesity is an urgent problem of pediatric endocrinology due to the widespread occurrence, the development of metabolic complications and their steady tracking into adulthood. The developed clinical guidelines are the main working tool of the practitioner. They briefly and structurally present the main information about the epidemiology and modern classification of obesity, methods of its diagnosis and treatment based on the principles of evidence-based medicine.

Mutations in the gene DHH are an extremely rare cause of disorders of sex development 46,XY (DSD,46XY). The article describes the clinical cases of two unrelated patients with gonadal dysgenesis 46,XY with female phenotype. By using a next generation sequencing method, in both cases the same biallelic variant substitution c. 419T>G in the DHH gene was revealed. Taking into account the data on the role of DHH in the formation of the nervous system, the diagnosis of minifascicular polyneuropathy at the preclinical stage was confirmed in both cases. These cases demonstrate the value of using NGS, which allows simultaneous analysis of a wide range of candidate genes in DSD and the diagnosis of comorbidities before the development of the clinical picture. These are the first descriptions of patients with mutations in the DHH gene in the Russian population.

The thyroiditis in children are urgent problem of pediatric endocrinology due to the widespread occurrence and characterized by clinical and pathogenetic heterogeneity. The developed clinical guidelines are the main working tool of the practitioner. They briefly and structurally present the main information about the epidemiology and modern classification of thyroiditis, methods of their diagnosis and treatment based on the principles of evidence-based medicine.

Public organization “Russian Association of Endocrinologists”. Clinical guidlines.

The materials of the National Consensus reflect the modern domestic and international experience on this issue. Before conducting a specialized endocrinological examination of a short child, all other causes of short stature should be excluded: severe somatic diseases in a state of decompensation that can affect growth velocity, congenital systemic skeletal diseases, syndromic short stature (all girls with growth retardation require a mandatory study of karyotype, depending on the presence or absence of phenotypic signs of Turner syndrome), endocrine diseases in decompensation. A specialized examination of the state of GH-IGF-I axis is carried out when the proportionally folded child has pronounced short stature: if the child’s height is < –2.0 SDS, if the difference between the child’s height SDS and child’s midparental height SDS exceeds 1.5 SDS and/or a low growth velocity. The consensus reflects clear criteria for the diagnosis of GH-deficiency, central hypothyroidism, central hypocorticosolism, central hypogonadism, diabetes insipidus, hypoprolactinemia, and also the criteria for their compensation. The dose of somatropin with GH-deficiency in children and adolescents is 0.025–0.033 mg/kg/day. With total somatotropic insufficiency, especially in young children, it is advisable to start therapy with somatropin from lower doses: 25–50% of the substitution, gradually increasing it within 3–6 months to optimal. In children with a growth deficit when entering puberty, the dose may be increased to 0.045–0.05 mg/kg/day. With the development of side effects, the dose of somatropin can be reduced (by 30–50%), or temporarily canceled (depending on the severity of the clinical picture) until the complete disappearance of undesirable symptoms. With swelling of the optic nerve, treatment is temporarily stopped until the picture of the fundus of the eye fully normalizes. If therapy has been temporarily discontinued, treatment is resumed in smaller doses (50% of the initial) with a gradual (within 1–3 months) return to the optimum. GH treatment at pediatric doses not continue beyond attainment of a growth velocity below 2–2.5 cm/year, closure of the epiphyseal growth zones, or earlier, when: the achievement of genetically predicted height, but not more than 170 cm in girls, 180 cm in boys, the patient’s desire and his parents / legal representatives satisfied with the achieved result of the final height. Re-evaluation of the somatotropic axis is carried out after reaching the adult height, after 1–3 months GH therapy will be discontinued. Patients with isolated GH-deficiency or patients with 1 (besides GH) pituitary hormone deficiencies in the presence of a normal IGF-1 level (against the background of somatropin withdrawal) and not having molecular genetic confirmation of the diagnosis need re- evaluation. Patients with two or more (besides GH) pituitary hormone deficiencies, acquired hypothalamic-pituitary lesions due to operations on the pituitary and irradiation of the hypothalamic-pituitary area (if the IGF-1 level is low against somatropin withdrawal), specific pituitary/ hypothalamic structural defect on MRI, gene defects of the GH-IGF-I system do not need re- evaluation. If GH deficiency is confirmed, treatment with somatropin is resumed at metabolic doses of 0.01—0.003 mg/kg/day under the control of the IGF-I level in the blood (measurement 1 time in 6 months), the indicator should not exceed the upper limit of the reference value for the corresponding age and floor.

Persistent müllerian duct syndrome (PMDS) is a rare variant of the disorder of sex development (DSD) 46,XY characterized by the presence of Müllerian duct derivatives in 46,XY males. Since cryptorchidism is the only external manifestation of PMDS, until recently, PMDS was not diagnosed in patients and detection of Müllerian duct derivatives during the surgical treatment of cryptorchidism in patients with 46,XY karyotype was regarded as a variant of gonadal dysgenesis, leading to an erroneous choice of treatment strategy in these patients. Only the development of the molecular diagnostics methods, in particular, new generation sequencing, which enable simultaneous investigation of several candidate genes, provided accurate differential diagnosis of the PMDS. This article reports a clinical case of late diagnosis of the familial form of PMDS caused by mutation in the AMH gene. Detected persistent Müllerian derivatives in combination with agenesis of the testicle in the proband at an early age led to the diagnosis gonadal dysgenesis. Given the proven high risk of malignization of the gonads located outside the scrotum in patients with gonadal dysgenesis, the patient underwent removal of the only gonad located in the inguinal canal. The correct diagnosis was established after a comprehensive molecular genetic study using a new generation sequencing with the «disorders of sex development» panel. This study detected a homozygous mutation in the AMH gene.