2.1 Study population
Adult, malignancy, high-grade colonic dysplasia, tuberculosis, UC, leukopaenia, acute coronary heart disease
HEPATITIS B, COLONIC CANCER, TUBERCULOSIS, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, GASTRIC ULCERS, INFECTION
Adult patients [between 18 and 80 years] with a confirmed diagnosis of UC were enrolled at six hospitals in the Netherlands [two academic and four non-academic teaching hospitals]. Eligible patients had an indication to start oral prednisone or budesonide treatment, based on clinical and endoscopic signs of active UC, despite daily use of ≥2 g oral 5-aminosalicylates [5-ASA]. Patients with previous exposure to thiopurines or biologic agents were excluded. Pregnant patients were excluded, as well as patients with known chronic obstructive pulmonary disease, acute coronary heart disease, active malignancy, a history of high-grade colonic dysplasia or colonic cancer, previous [subtotal] colectomy, concomitant medication use interfering with mercaptopurine metabolism, gastric ulcers or active substance misuse. Additional exclusion criteria were a positive tuberculosis screening test, active hepatitis B or C infection, leukopaenia [leukocyte count <1.8 × 10