Idiopathic multicentric osteolysis presents early and is not linked to chromosome 18q21.1

The condition is inherited as an autosomal dominant trait (MIM 166300) but many isolated or de novo cases have been described. 2-5 Autosomal recessive inheritance has also been suggested. 6 The symptoms may present as early as the first year of life 2 and most often affect the carpal and tarsal bones in an inflammatory-like fashion. A typical facies develops in these patients, including maxillary hypoplasia and associated exophthalmia, a slender nose, and micrognathia. 2 3 7 Nephropathy has been associated with IMO in some families. 8 Familial expansile osteolysis had been linked to chromosome 18q21.1-q22, 9 and mutations in the TNFRSF11A gene have recently been reported to cause familial expansile osteolysis. 10 We present a three generation family in which nine members are affected with idiopathic multicentric osteolysis (fig 1 ).