Résumé
Langerhans cell histiocytosis (LCH) is an abnormal clonal proliferation of Langerhans cells. The prognosis varies depending on the form of the disease and organ damage. Any organs and systems can be involved in the pathological process in various combinations. A poor response to standard therapy and an unfavorable prognosis are characteristic of patients with a multisystem form of LCH and involvement of organs at risk. Skin lesions are a classic sign of LCH. Purpose - to describe the complexity and duration of diagnosis of LCH with multisystem damage in a boy aged 2 years and 2 months, infected with poliomyelitis and coronavirus. Clinical case. The first clinical manifestations of LCH in the child debuted with an eczematous-seborrheic rash on the scalp with spread to the limbs and trunk. The child was treated for toxicoderma, hemorrhagic vasculitis at the place of residence for 6 months. The boy lost 1.5 kg of body weight in 1 month. At the time of hospitalization, seborrheic-eczematous rashes on the skin with a hemorrhagic component, trophic-inflammatory changes in the nails of the hands, signs of protein-energy deficiency, stomatitis, gingivitis, hepatosplenomegaly, polyserositis, diabetes insipidus, osteolytic foci of the frontal bones were found. Results of the tests: anemia, thrombocytopenia, hypoproteinemia and hypoalbuminemia, coagulation disorders. The patient had the onset of lower flaccid paraparesis, muscle hypotonia. The boy was diagnosed with a number of infectious complications, including poliomyelitis (a derivative of vaccine poliovirus type 2), COVID-19. The child received LCH-III cytostatic therapy with a positive effect. The research was carried out in accordance with the principles of the Helsinki Declaration. The informed consent of the patient was obtained for conducting the studies.Copyright © 2023 Institute of Physics of the Russian Academy of Sciences. All rights reserved.