Chondrocalcinosis 2 (CCAL2)

Chondrocalcinosis 2

Chondrocalcinosis 2 (CCAL2; MIM 118600), also known as calcium pyrophosphate dihydrate deposition disease (CPPDD), is an autosomal dominant disorder caused by mutations in the ANKH gene. In general, chondrocalcinosis is characterized by the deposition of calcium containing crystals in joints which can cause recurrent acute attacks of joint pain and synovitis (pseudogout). If chronic, this can lead to degenerative joint disease. Chondrocalcinosis 2 is typically polyarticular in nature and has an earlier age of onset, during the third or fourth decade, compared to other types of chondrocalcinosis. The calcium containing crystals in chondrocalcinosis 2 are composed of calcium pyrophosphate dihydrate (CPPD). Patients with chondrocalcinosis 2 usually do not display extraarticular calcifications. Chondrocalcinosis 2 is allelic to autosomal dominant craniometaphyseal dysplasia (MIM 123000). Some members of one family with a defined ANKH mutation have features of both chondrocalcinosis 2 and craniometaphyseal dysplasia.