The high prevalence of pigmented skin neoplasms, due to the peculiarities of tumor progress, including melanoma of the skin, in the pediatric population, brings the problem of rational removal of pigmented skin objects in one of the most relevant. Given the existing complications and negative treatment results, it requires an immediate solution, taking into account the capabilities of modern equipment and minimally invasive treatment approaches to the treatment of this complex pathology. Purpose - to improve the quality of treatment of patients by clarifying the indications for surgical treatment of skin pigmented nevi and the method without recurrent removal. Materials and methods. The paper analyzes 550 clinical cases of melanocytic nevus of the skin of different localization in children of different ages who were hospitalized in the pediatric surgery clinic of Vinnytsya National Medical University M.I. Pirogov during 2009-2020. All observations were divided into two periods: retrospective (2009-2017) - 350 patients; prospective (2018-2020) - 200 patients. Among patients with a retrospective period, 11 patients were diagnosed with melanoma, and among children with a prospective period - 3 patients. Analysis of medical records revealed 18 (3.85%) cases of recurrent (prolonged) melanocyte nevi in children of different ages, 10 (55.56%) girls and 8 (44.44%) boys. Results. In the prospective study group 138 patients regardless of age and sex based on the obtained data on the optimal configuration of the postoperative wound and the most rational way to remove pigmented skin tumors, managed to avoid incomplete removal of the object with good aesthetic results. According to the data obtained, the index of validity of biopsies is needed to determine melanoma of the skin during the entire study period was 39.29. At the same time, for the retrospective period of observation index of validity of biopsies was in the range of 31.82, in the prospective period - 66.66, namely the decrease in the value of the index was 2.09 times, or 52.27%. Conclusions. The use in clinical practice of the proposed method of incisional biopsy has reduced the number of recurrences of the pathology by 5.2 times from 2.60% in retrospect to 0.50% in the prospective period (p<0.05). The rational individual approach to clarify the indications for surgical treatment of pigmented skin nevi allowed to reduce by 52.7% the index of validity of biopsies. The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local ethics committee of all participating institutions. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors. Key words: pigmented skin neoplasms, children, biopsy, recurrences.

Acute appendicitis is the most common cause of abdominal pain, which requires immediate surgical intervention in children and is a truly urgent pathology of the gastrointestinal tract. Preliminary diagnosis is made primarily on the basis of clinical data, however, in the course of further examination an integral part of the diagnostic process are additional research methods such as general blood tests, ultrasound examination of the abdominal cavity. Purpose - to determine the complex diagnostic significance of the ultrasound method of research in patients with abdominal pain. Materials and methods. A retrospective analysis of 200 medical records of inpatients treated at the Vinnytsia regional clinical hospital (Ukraine) for appendicitis in 2021 was conducted. Our study was conducted in the conditions on the basis of the analysis of medical records of inpatients. During the above-described period, ultrasound examination was performed in Vinnytsia regional clinical hospital in 200 girls with abdominal pain. Ultrasound examination was performed with Doppler scanning on ultrasound machines «SAMSUNG H 60» (South Korea) and «SAMSUNG» LS 22 EMU 1 HS (Seoul. Korea, 2016). The age distribution of girls was as follows: 0-3 years - 8 (4%) girls, 4-12 years - 86 (43%) children, 13-18 years - 106 (53%) girls. Results. Simultaneous comparison of the dynamics of local changes in the clinical picture, hemogram, the amount of endogenous intoxication and visual findings on ultrasound of the abdominal cavity avoids unwarranted surgery in patients with abdominal pain and direct the doctor to the correct tactical course in doubtful cases. Conclusions. Only a properly collected history, assessment of physical and clinical and laboratory parameters and data of laboratory methods of examination, the involvement of the necessary narrow specialists can avoid mistakes in the diagnosis of acute appendicitis in children. It is expedient and justified in the diagnostic assessment of the clinical picture in case of suspicion of acute appendicitis to compare the indicators of the total index of endogenous intoxication with the ultrasound method of appendix removal in the dynamics of the pathological process. The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local ethics committee of all participating institutions. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Key words: ultrasound, appendicitis, diagnosis, surgery.