The impact of intestinal resection on serum levels of anti-Saccharomyces cerevisiae antibodies (ASCA) in patients with Crohn's disease.

Background Antibodies to Saccharomyces cerevisiae (ASCA) are highly prevalent in sera of patients with Crohns disease and have been proposed to identify subgroups of patients with a disabling disease course. Aim To investigate the impact of intestinal resection on serum levels of ASCA in patients with Crohns disease and the predictive value of ASCA levels on surgical recurrence. Methods Sera from 60 patients who underwent curative intestinal resection due to stricturing and/or penetrating complications were collected preoperatively and during post-operative follow-up (week 2, months 4, 8 and 11 +/- 1). Measurement of ASCA IgG and IgA isotypes were performed using ELISA. Re-operation rate was associated with ASCA status and serum levels. Results At baseline 44/60 (73%) of patients were rated as positive for ASCA IgG, 45/60 (75%) for ASCA IgA and 52/60 (87%) as positive for at least one of both. ASCA serum levels remained stable during first year from resection. After a median of 106 months 10 of 40 (25%) patients with long-term follow-up underwent one or more intestinal re-operations. Neither ASCA positivity nor absolute ASCA serum levels were predictive of surgical recurrence. Conclusions Serum ASCA levels remain stable after curative intestinal resection in Crohns disease. This indicates the persistence of both stimulus and immunological mechanism operative in the production of ASCA even after complete surgical resection of macroscopically inflamed intestinal tissue. After intestinal resection, neither ASCA positivity nor ASCA serum levels predict the risk of surgical recurrence during long-term follow-up.