Calvarial "doughnut lesions": Clinical spectrum of the syndrome, report ona case, and review of the literature

Many pathologic fractures, lumps on the head, elevated serum alkaline phosp hatase (ACP) levels, and dental caries are the main characteristics of the rare autosomal dominantly inherited calvarial "doughnut lesions" (MIM 12655 0), We report the sporadic case of a Is-year-old patient who has had 10 pat hologic fractures between age 6 weeks and 15 years. An elevated serum ALP l evel was found at age 11 and skull lumps at age 15; radiography showed fron tal and parietal round radiolucencies surrounded by sclerotic bone comparab le to doughnuts, Magnetic resonance imaging (MRI) showed skull lesions at a n early stage. Because the findings are reminiscent of osteogenesis imperfe cts (OI), collagen types I, III, and V were analyzed in fibroblasts and sho wn to be normal in terms of quantities, proportions, electrophoretic mobili ty, and thermostability, Thus, this rare syndrome can be distinguished from OI by collagen analysis and MRI of the skull at an early stage, even befor e palpable skull lesions appear. (C) 2001 Wiley-Liss, Inc.