Scatter plot of serum GM-CSF Ab Concentration by Disease Categories. Serum GM-CSF Ab concentration was measured by ELISA and is shown as the median(IQR). Differences between groups were tested with the Kruskal-Wallis test, **p<0.009. Among CD patients (n=114), the median (IQR) GM-CSF Ab was 2.3 mcg/mL (0.5, 6.6) and was significantly higher than that of the chronic abdominal pain patients (n=22) with a median (IQR) of 0.4 mcg/mL (0.6, 1.3), p<0.05. Note: Abd pain=abdominal pain, IC = Indeterminate Colitis, UC = Ulcerative Colitis.