Absence of ANCA in Mexican patients with Takayasu's arteritis.

Antineutrophil cytoplasmic autoantibodies (ANCA) were sought in 43 sera from 39 Mexican patients with typical Takayasu's arteritis (TA), (5 with active and 34 with inactive disease), and in a comparative group comprising 50 sera. Results were negative in all cases. This suggests that ANCA are not a serologic feature in TA per se, even during its active stage. ANCA positivity in TA, when present, may be a non-related phenomenon and probably identifies a subset of patients with atypical forms of TA or a polyangiitis overlap syndrome.