To assess the diagnostic usefulness of digit joint aspiration in patients with involvement of one or more digit joints.
All patients who underwent digit joint aspiration during a rheumatology outpatient visit between 1994 and 1998 were included. Fine needles (25 or 28 G) were used, and the aspirate was immediately examined under the microscope to determine the leukocyte count and to look for crystals under polarized light.
Digit aspiration yielded a diagnosis of crystal deposition arthropathy in 20 (29%) of the 71 patients (gout, N = 14; calcium pyrophosphate dihydrate crystal deposition disease, N = 6). In 28 patients, the amount of fluid was too small to allow analysis. The leukocyte count indicated inflammatory disease in eight of the remaining 23 patients and mechanical disease in 15.
Fine-needle aspiration of symptomatic digit joints provided the diagnosis in two-thirds of patients.