ABSTRACT
The authors describe a clinical case of a protracted course of a new coronavirus infection in a child with the development of severe complications against the background of a hereditary disease of neurocutaneous melanoblastosis, Bloch–Sulzberger syndrome. The progression and severity of the disease was caused by acute onset, lack of specific therapy at the onset of the disease and late seeking for medical help. For 2 months, the patient had long-term persistent SARS-CoV-2 viremia with the development of viral-bacterial pneumonia. A defect in the immune system in the early period of the disease contributed to the protracted course of the disease and the development of complications. The outcome of the disease in this patient was predetermined by the combination of etiological factors tropic to the respiratory system, the presence of background genetic pathology with the development of a pathological response of the innate and adaptive immune system of the body to massive replication of SARS-CoV-2 with the development of the late phase of COVID-19. © 2021 National Academy of Pediatric Science and Innovation. All rights reserved.