Brittle Bone Disease: A Case Report

Osteogenesis imperfecta (OI) is a rare genetic disorder. Due to considerable phenotypic variability, a classification was developed for OI subtypes based on clinical features and disease severity. A seven-day-old female was born at 40+1 weeks of gestation whose mother received routine antenatal care and had an uneventful pregnancy. In delivery, the newborn suffered bilateral collarbone fractures. After a week, she returned to an unscheduled appointment at the healthcare family unit due to an inconsolable cry and pain during mobilization of the left lower limb with three days of evolution, which were noticed by her parents. On examination, she presented edema in the right coxofemoral joint, asymmetry in the folds, and inconsolable crying during the mobilization of both hip joints. She was sent to the emergency department, where a pelvis X-ray was performed revealing a bilateral fracture of the femurs. During hospitalization, a genetic study revealed pathogenic variants of the WNT1 gene, which causes OI type XV. When a newborn presents with fractures, the main differential diagnosis is physical abuse. However, this was ruled out as we knew her mother and family, leaving no other possible evidence of abuse. OI was a highly probable diagnostic hypothesis due to the presence of two other cases of this type of OI in the same region of origin, even though her parents were not consanguineous and there was no history of fractures in their families. Although OI is a rare condition, the diagnosis was immediately suspected because there were two confirmed cases of this type in the same geographic area as our patient. Additionally, she had bilateral clavicle fractures at birth with no obvious signs or risk factors for abuse. As family doctors, it is our aim to support this family throughout their journey and provide the child with the best care possible.