Juvenile Paget disease
is a very rare condition that affects bone growth. This condition causes bones to be abnormally large, misshapen, and easily broken (fractured). Signs and symptoms usually appear in infancy or early childhood. As bones grow, they become weaker and more deformed. This condition affects the entire skeleton, resulting in widespread bone and joint pain. The bones of the skull tend to grow unusually large and thick, which can lead to hearing loss. The condition also affects bones of the spine (vertebrae), leading to abnormal curvature of the spine. Additionally, weight-bearing long bones in the legs tend to bow and fracture easily, which can interfere with standing and walking. Juvenile Paget disease is caused by mutations in the TNFRSF11B gene and is inherited in an autosomal recessive fashion. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.