<qa>  What is the CDAI score of patients with less than 150?Patients with a CDAI score of less than 150 will begin ECP treatments as soon as possible. Those with scores from 150 to 219 will have their corticosteroid dose increased enough to bring their CDAI score to below 150 before beginning ECP. Patients who do not achieve a CDAI of less than 150 after 4 to 6 weeks of increased corticosteroids will be excluded from the study. 