Our objective was to prospectively evaluate the results of TST and QFT in rheumatology patients in different therapeutic phases.
Methods: All adults with inflammatory arthritis assisted in a hospital out-clinic were derived for enrollment, excluding patients on treatment with >10 mg/d of Prednisone or with active TB. All of them were studied with X-ray, QFT [Cellestis®] and PPD (0.1 mL of the PPD RT23). Structured interview was performed to collect epidemiological and clinical factors. Therapy of the rheumatic disease was classified as follow: Phase 1: anti-inflammatories; Phase 2: disease-modifying antirheumatic drugs; Phase 3: biologic therapy.
Results: From March 2011 to June 2014, 202 were enrolled. Underlying conditions were: 134 peripheral arthritis (PA), 49 central arthritis (CA) and 19 “other connective tissue disorders” (OC). The three groups were comparable according to TB epidemiological indicators. The global index of agreement between QFT and TST was moderate (kappa: 0.460) no differences according to treatment phase (1: 0.331, 2: 0.380, 3:0.419) or type of rheumatic disorder (PA: 0.460, AS: 0.459, OC: 0.477). The main discrepancy, PPD+/QFT- (39 patients, 19%) was only statistically associated to prior BCG vaccination (p<0.001) even in patients with TB epidemiological indicators. QFT+/PPD- was an unusual result (8 patients, 4%) but mainly appeared in patients in phase 1 with a shorter length of rheumatic disease (p=0.04). INH hepatotoxicity (6/60) was always mild. Clinical follow-up of enrolled patients is still on going. There was no case of TB.
Conclusion: In our environment, QFT and TST should be used simultaneously in patients with rheumatology diseases in order to detect the highest number of rheumatology candidates to receive INH. We could not find any impact of type of disease or previous treatment.
M. J. Ruiz-Serrano, None
M. Montoro, None
M. Kestler, None
O. Aldecoa-Otarola, None
E. Bouza, None