Clinical and radiographic study of bone and joint lesions in 26 dogs with leishmaniasis.

Twenty-six dogs with parasitologically confirmed leishmaniasis and abnormalities of gait were studied to determine the most common radiological patterns of bone and joint lesions. The clinical findings included either lameness, joint pain and crepitation, soft tissue swelling and/or muscle atrophy. Bone lesions were observed radiographically in 12 of the 26 dogs; the radius and ulna were affected in seven, the tibia in six and the femur in six. Joint lesions were observed radiographically in 15 of the 26 dogs; the carpus and stifle were affected in all 15, and the tarsus in nine. There was a tendency for the bones and joints to be affected bilaterally. The radiographic patterns observed were different in the long bones and the joints. In the long bones, the most common pattern was periosteal and intramedullary proliferation, involving the diaphyses and related to the nutrient foramen; in the joints, two patterns, either non-erosive or erosive polyarthritis with soft-tissue swelling, were observed. The changes observed in the synovial fluid were associated in most cases with osteolytic lesions. However, Leishmania organisms were identified in the synovial fluid from joints without bony radiographic changes.