Genética da osteogênese imperfeita e benefícios da oxigenação hiperbárica

Abstract

Osteogenesis imperfecta (OI) is a clinically heterogeneous group of genetic disorders characterized by increased bone fragility of varying severity, depending on age at onset, disease severity, and the presence of additional findings such as dentinogenesis imperfecta. The common feature of all types is bone fragility, which leads to multiple fractures. In 95% of cases, OI is caused by pathogenic variants in the COL1A1 and COL1A2 genes (17q21.33 and 7q21.3), which encode the alpha 1 and alpha 2 chains of type I collagen and are inherited in an autosomal dominant manner. Its prevalence is estimated to range from 1 in 10,000 to 1 in 20,000. There are also autosomal recessive forms, which are always moderate or severe and may be accompanied by hypotonia, such as those caused by the CRTAP and PPIB genes (1p34.1, 3p22, and 15q21-q22). Clinical diagnosis is based on skeletal and extraskeletal findings, including osteoporosis and the presence of Wormian bones. The differential diagnosis includes conditions associated with susceptibility to fractures, whether hereditary, such as hyperphosphatasia and hypophosphatasia, or non-hereditary, such as leukemia, nutritional deficiencies, and, particularly in children, physical abuse. The management and treatment of OI require a multidisciplinary approach involving genetics, physiotherapy, rehabilitation, and traumatology, as well as hyperbaric medicine to accelerate bone callus formation. Pharmacological treatment is based on bisphosphonates in severe forms, although they are not curative, and on lifelong prevention of vitamin D and calcium deficiency. Surgery may be used to correct bone and spinal deformities and to prevent long-bone fractures through intramedullary osteosynthesis. Physiotherapy is also important because it improves autonomy, helps assess the presence of motor impairment, and reduces falls. Moderate non-contact sports, such as swimming, may therefore be beneficial for these patients. Hyperbaric medicine is a therapeutic tool to be considered because it stimulates osteogenesis through the activation of osteoblasts and osteocytes, thereby accelerating healing processes over time and improving the quality of bone callus formation.