Sclerosing bone disorders

Increased skeletal mass is caused by many rare osteochondrodysplasias and by various dietary, metabolic, endocrine, hematological, infectious, and neoplastic disorders. This chapter reviews principally the key Mendelian diseases. It discusses clinical presentation, radiological features, laboratory findings, histopathological findings, etiology and pathogenesis, diagnosis, and treatment of various sclerosing bone disorders. Osteopetrosis (OPT), carbonic anhydrase II (CA II) deficiency, pycnodysostosis, progressive diaphyseal dysplasia (PDD), osteopoikilosis (OPK), osteopathia striata, melorheostosis (MEL), axial osteomalacia, fibrogenesis imperfecta ossium (FIO), pachydermoperiostosis, and Hepatitis C-associated osteosclerosis are some of the osteosclerosis diseases. The chapter lists many additional conditions associated with focal or generalized increases in skeletal mass. Sarcoidosis characteristically causes cysts within coarsely reticulated bone. However, sclerotic areas occasionally appear in the axial skeleton or long bones. Diffuse osteosclerosis reflects secondary but not primary hyperparathyroidism.