Apical fibrobullous lung disease in spondyloarthritis patients with biologic DMARDs indication

The rate of pleuroparenchymal involvement in patients with SpA varies widely, from 0% to 85%. The most common form is apical fibrobullous disease (AFLD). The aim of this study was to determine the incidence of AFLD and associated factors in SpA patients under and/or planned to start biologic DMARDs (bDMARDs) therapy.

The records of 3021 SPA patients registered with HUR-BIO who had indication of bDMARDs between 2010 and 2021 were scanned. The study included 2489 patients with at least one chest radiograph (X-ray). Patient demographics, comorbidities, laboratory data, bDMARDs used, baseline DASs, and purified protein derivative and/or QuantiFERON test results before initiation of bDMARDs were recorded.

Of the 2489 patients, 36 (1.4%) were found to have AFLD by X-ray and/or CT. The mean disease duration was 11.7 (7.1) years. Patients with AFLD were more likely to be male [28 (77.8%) vs 1321 (53.9%), P = 0.004], older [56.3 (10.5) years vs 44.8 (11.4) years, P < 0.001], heavy smokers [27 (79.4%) vs 1468 (60.9%), P = 0.028] and have had longer disease duration [17. 7 (9.7) years vs 11.6 (7) years, P = 0.001]. QuantiFERON positivity was higher in the AFLD group [9 (36%) vs 309 (16.1%), P = 0.013]. While treatment with adalimumab was less preferred in those with AFLD, treatment with etanercept was more frequently preferred.

As the radiological findings of AFLD can be confused with those of tuberculosis, special attention should be paid to differentiating between tuberculosis and the disease in males and in patients who have had long disease duration.