AB0969 The Role of High Resolution CT Scanning in The Assessment of Patients with Inflammatory Joint Disease (IJD) on Biologics

Background Biologic therapy (BT) in the treatment of IJD is now well established. The risks and potential complications of this modality of the treatment including infections and interstitial lung pathology have been described previously including in reports from several national registry databases such as the BSRBR. Furthermore the prevalence of lung disease in rheumatoid IJD is estimated at 5%. HRCT scanning for lung disease is therefore an important but under-utilized means of objective assessment of patients with IJD particularly in later stages of disease and when medical treatment is escalated to include immunomodulatory and biologic therapies. Objectives Our data examines the role of HRCT in the assessment of IJD patients before and after introduction of biologic therapies to consider the merits of this investigation in the intermediate and long term surveillance of IJD and biologic therapies. Methods Hospital records of patients with IJD under the care of one rheumatologist (MN) submitted for assessment for biologics were assessed. Specific diagnosis, treatment regimens and progression to biologic therapy were documented along with a record of submission for HRCT. Outcome and changes in treatment over time as well as follow up scan results were documented and analysed. Results Of the 130 patients assessed for BT in the 5 year period up to 2015, 106 (82%) had HRCT prior to commencing BT. 92 (71%) had normal scans. A total of 116 patients were submitted for BT (93 anti TNF and 23 other) of these 70 (60%) were also on MTX. Thus 10 patients had BT without HRCT. 14 (11%) had abnormal scans (including ground glass change, bronchiectasis, COPD) and were not commenced on anti TNF, Rituximab or other BT. Of the 130 patients 87 (67%) had RA of which 71 (81.6%) were seropositive. Of the 14 with abnormal scans, 8 were seropositive and 8 were on MTX. Of the 93 patients started on Anti TNF, 35 (37.6%) were discontinued/switched to another BT for a variety of reasons including inefficacy and side effects. Of the anti-TNF start-ups, 29 (31%) had progressive changes on repeat HRCT within 0 to 12 months. Of these 14 were switched to Rituximab with no further change in HRCT. Repeat HRCT scan data is available in only 5 of 15 patients switched to a second anti TNF, in three of which progression of lung changes was noted. Conclusions These preliminary data reveal the importance of HRCT scanning in the pre-assessment and monitoring of patients requiring BT for IJD. Progression of lung disease was seen in 31% patients on anti TNF. We recommend early repeat scans if any adverse effects are experienced or a change in BT planned due to lack or loss of efficacy. As lung disease is now recognised as the main non-infective cause of mortality in IJD, consideration should be given to routine review HRCT at 12 months after introduction of BT and then at regular (no longer than 3 year) intervals to monitor change even in asymptomatic patients controlled on biologics. Disclosure of Interest None declared