Rhesus Monkeys (Macaca mulatta) as a Model For Calcium Pyrophosphate Dihydrate Crystal Deposition Disease

Abstract
Calcium pyrophosphate dihydrate crystal deposition disease (CPDD) was recognized in 4 of 30 free‐ranging rhesus macaques. By means of tissue radiography, focal radiodensities were noted in lumbar intervertebral discs, menisci, and articular cartilage. Crystal deposits were identified as calcium pyrophosphate dihydrate (Ca2P2O7·2H2O) by means of X‐ray diffraction. The pathogenesis of calcium pyrophosphate dihydrate arthropathy in man remains elusive. However, with the recognition of this arthritis in a well defined population of aged nonhuman primates, a model now exists to facilitate the study of this disease.