Seronegative inflammations of the ankle and foot: diagnostic challenges

Seronegative inflammatory disease was diagnosed in seven patients who had pain, swelling, and redness of the foot and/or ankle. Since the clinical findings mimicked infection, tendinitis, fasciitis, or chronic strain, the initial diagnosis was erroneous and treatment ineffective. In addition to the test for the HLA-B27 antigen, technetium-99m-diphosphonate scintigraphy and magnification roentgenograms have proved valuable tools. Increased isotope uptake was found in all involved extremities, and magnification roentgenograms helped to detect early and subtle lesions of bone. The lesions comprised cortical erosion, increased intracortical absorption of bone, periosteal reactions, and osteoporosis. The response to anti-inflammatory drugs was good in all seven patients. Limited and preliminary follow-up data, including repeat bone scans, suggest that the inflammation may be of a transient nature.