Familial osteoarthritis and Milwaukee shoulder associated with calcium pyrophosphate and apatite crystal deposition

OBJECTIVE

To characterize and define the phenotypes observed in a large Italo-Argentinean kindred with osteoarthritis, chondrocalcinosis, and Milwaukee shoulder (MS).

METHODS

Seventy-five members were evaluated with a history, examination, and radiographs of shoulders, spine, hands, and knees. Superior subluxation of the glenohumeral joint was graded using shoulder radiographs and tomography and nuclear magnetic resonance imaging and 3 dimensional computed tomography was performed on selected members. In 31 family members peripheral blood DNA was utilized for genetic linkage analysis of several candidate gene loci previously linked to chondrocalcinosis phenotypes, as well as those implicated in the proper patterning of skeletal elements and cartilage differentiation. In addition, direct sequence analysis of type II collagen gene (COL2A1), the gene that codes for the major structural protein of cartilage, was undertaken in 3 affected and 3 unaffected members of the family.

RESULTS

MS was seen in one member of the first generation and 6 members of the 2nd generation, while 8 members of the 3rd generation showed an incomplete form of MS. Isolated superior subluxation of the shoulder was seen in 16 other family members of the 3rd and 4th generations. Osteoarthritis of the spine and peripheral joints was seen in 31 affected members, while chondrocalcinosis was observed in 6 members of the first generation. Shoulder synovial fluid from 2 patients showed the presence of both apatite and calcium pyrophosphate dihydrate crystals. Direct analysis of the COL2A1 gene indicated no known disease determining mutations in affected members, thus excluding this gene as a candidate gene in this family. Genetic linkage to several candidate loci, including the chondrocalcinosis loci on chromosomes 5p and 8q, as well as loci for HOX A and C were also excluded. Linkage analyses of other loci for the HOX B and D genes and the PAX 1 and 9 genes were uninformative in this kindred.

CONCLUSION

This kindred illustrates an unusual type of osteoarthritis with secondary intraarticular and periarticular calcification and MS in the most severely affected elderly members. A search for linkage to some potential candidate genes was either excluded or uninformative. Further linkage analysis to identify potential candidate genes is in progress.

Refinement of the chromosome 5p locus for familial calcium pyrophosphate dihydrate deposition disease

Familial calcium pyrophosphate dihydrate deposition disease (CPPDD) is a disease of articular cartilage that is radiographically characterized by chondrocalcinosis due to the deposition of calcium-containing crystals in affected joints. We have documented the disease in an Argentinean kindred of northern Italian ancestry and in a French kindred from the Alsace region. Both families presented with a common phenotype including early age at onset and deposition of crystals of calcium pyrophosphate dihydrate in a similar pattern of affected joints. Affected family members were karyotypically normal. Linkage to the short arm of chromosome 5 was observed, consistent with a previous report of linkage of the CPPDD phenotype in a large British kindred to the 5p15 region. However, recombinants in the Argentinean kindred have enabled us to designate a region<1 cM in length between the markers D5S416 and D5S2114 as the CPPDD locus.