pediatrics
Osteosclerosis
Osteopetrosis with precocious manifestations
This type of osteopetrosis is Autosomal Recessive , malignant, and congenital, manifesting during infancy. It is uncommon, frequently lethal, and often due to a mutation in the osteoclast-associated gene Initial symptoms of osteopetrosis with precocious manifestations include failure to thrive, spontaneous bruising, abnormal bleeding, and anemia. Palsies of the 2nd, 3rd, and 7th cranial nerves and hepatosplenomegaly occur later. Bone marrow failure (anemia, overwhelming infection, or hemorrhage) usually causes death in the first year of life. Diagnosis of osteopetrosis with precocious manifestations is suspected by the presence of bony overgrowths in the context of anemia, unusual bleeding, and poor growth. Typically, plain x-rays are done, along with complete blood count and coagulation tests. General increased bone density is the predominant feature on x-ray. Penetrated x-rays of long bones show transverse bands in the metaphyseal regions and longitudinal striations in the shafts. As the disorder progresses, the ends of the long bones, particularly the proximal humerus and distal femur, become flask-shaped. Characteristic endobones (bone within a bone) form in the vertebrae, pelvis, and tubular bones. The skull becomes thickened, and the spine has a rugby-shirt appearance. Hematopoietic Stem Cell Transplantation has had excellent results. However, prognosis is poor with human leukocyte antigen (HLA)–mismatched grafts. 