Agalactosyl IgG is elevated in patients with active spondyloarthropathy

Patients with rheumatoid arthritis or with Crohn's disease have deficient galactosylation of serum IgG [Gal(0)]. To study whether such deviation occurs in patients with spondyloarthropathy (SPA), we studied the percentage incidence of Gal(0) corrected for age [Gal(0)corr] in 47 SPA patients undergoing ileocolonoscopy and correlated the findings with clinical variables and prognosis of the patients. Gal(0)corr was elevated in 36% of the patients. Such patients had a higher number of inflamed joints (P < 0.02), higher ESR (P < 0.001) and CRP (P < 0.001). Elevated Gal(0)corr was also of prognostic significance: at 6-month follow-up those with elevated levels had a higher number of inflamed joints (P < 0.02) and ESR (P < 0.05). The presence of high Gal(0)corr did not associate with gut inflammation. In conclusion, a proportion of SPA patients has elevated levels of Gal(0), the amount of which correlates with severity of the disease and is a prognostic marker for chronicity of the disease.