The aim of this study was to evaluate in Crohn's disease the possible usefulness of alpha 1-antitrypsin clearance and fecal concentration in the early detection of postoperative asymptomatic recurrence. Eleven adult patients with small bowel Crohn's disease undergoing elective resection were enrolled in the study and prospectively followed for one year. Three, six, and 12 months after surgery the alpha 1-antitrypsin clearance and fecal concentration were measured, and the disease activity was assessed. All patients were free of active symptoms throughout the study. One year after surgery small bowel radiology was performed in all patients. Radiographic evidence of recurrent macroscopic disease was found in five of the 11 patients. Three months after surgery both alpha 1-antitrypsin clearance and fecal concentration were significantly lower (P less than 0.01) than before surgery. There was no difference at this time between patients with recurrence and those with no recurrence. In patients with recurrence both alpha 1-antitrypsin clearance and fecal concentration significantly increased at six months in comparison with the values at three months (P less than 0.02). Both measurements were significantly higher at six and 12 months in this group of patients than in those with no recurrence and in normal controls (P less than 0.01). At six and 12 months alpha 1-antitrypsin clearance was above the upper normal limit in all patients with recurrence. We conclude that fecal alpha 1-antitrypsin clearance is a noninvasive, inexpensive, sensitive marker of asymptomatic recurrence in CD patients who are under regular supervision after surgery.

We measured the serum C reactive protein (CRP) levels by a sensitive immunochemistry method in 101 outpatients with Crohn's disease enrolled in a prospective longitudinal study. At entry, 51 of the 101 patients had raised CRP levels, which showed good correlation with the clinical score. However, one-third of the patients with clinically active disease had normal CRP while one-third of the patients in clinical remission had a raised CRP. The longitudinal study showed that (a) in patients with active disease, CRP levels tended to decrease as the disease went into remission; (b) in patients who achieved remission, the likelihood of clinical relapse after 2 years of entry was higher in those with persistently raised CRP than in those with persistently normal CRP; and (c) in patients with quiescent disease at entry who remained in remission throughout the first year of the study, the likelihood of clinical relapse during the second year of the study was higher for those with persistently raised CRP than for the others. This study confirms that serum CRP is a useful laboratory index for supplementing clinical scores in patients with Crohn's disease, in monitoring the response to treatment, in helping to predict the course of the disease, and in contributing to defining subgroups of patients.