第21卷 　 第二期 　 Vol. 21, No. 2, December, 2007

Original Aiticles 原著

TNF-alpha –308A allele is associated with the presence of tophi: a preliminary study

Ben Yu-Jih Su1, Tien-Tsai Cheng1, Han-Ming Lai1, Ying-Chou Chen1, Chun-Kai Chiu1, Shan-Fu Yu1, Ko-Ming Lin2, Ming-Chi Yang1, Fu-Mei Su1, Chung-Jen Chen1

1Division of Allergy, Immunology and Rheumatology, Department of Internal Medicine, Chang-Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine 2Division of Allergy, Immunology and Rheumatology, Department of Internal Medicine, Chang-Gung Memorial Hospital-Chia-I Medical Center, Chang Gung University College of Medicine

Objective: To investigate the relationship between the presence of tophi and the TNF-alpha (TNFα) promoter –308G/A polymorphism in gouty patients. Methods: Thirty-seven gouty patients with any visible or palpable tophi on the four limbs joints were recruited as study subjects, and 40 gouty patients without visible or palpable tophi were recruited as controls. We collected and analyzed the clinical characteristics and laboratory data of patients in both groups. The TNFα –308G/A polymorphism was analyzed by PCR-RFLP methods. Results: There was no statistically significant difference in personal history, family history of gout or baseline laboratory data between patients with tophi and those without. There were statistically significant differences in favor of developing tophi in the heterozygote TNFα –308G/A (p=0.017, odds ratio 6.11, 95% C.I. 1.22-30.49). The frequency of the TNFα –308A allele was significantly higher in patients with tophi than in patients without (p=0.02, odds ratio 5.4, 95% C.I. 1.13-25.88). The –308 allele carriage of the G allele was 100% in both the tophi and non-tophi groups. In patients with tophi and without tophi, the –308 allele carriage of the A allele was 12.2% and 2.5%, respectively (p=0.035, odds ratio 4.87, 95% C.I. 0.99-24.00). Conclusion: To our knowledge, this is the first study to find that the TNFα –308A allele is associated with the presence of tophi in gouty patients. Further study of other polymorphisms in the TNF promoter is indicated to understand more about the tophi.

keyword Tophi, gout, tumor necrosis factor-alpha