The conversion rate of tuberculosis screening tests during biological therapies in patients with rheumatoid arthritis

Abstract

Screening for active tuberculosis (TB) and latent TB infection (LTBI) is mandatory to the initiation of biological therapy in patients with rheumatic diseases. To determine the prevalence of LTBI in patients with rheumatoid arthritis before treatment with biological therapy (anti-TNF, abatacept, and tocilizumab) and the rate of TB conversion during treatment in rheumatoid arthritis (RA) patients, we evaluated the file of 275 patients with RA treated with biological agents. We considered patients with negative baseline TB screening (tuberculin skin test (TST); quantiferon TB gold in tube (QFT-GIT); chest x-ray) and with rescreening for a TB assay every year. Twenty-six patients (10.6%) resulted positive to TB screening at baseline. Two hundred and forty-nine patients (mean age 55.3 ± 11.9; median 55.8 years, range 16-81.9; 210 female) with TB screening negative at baseline were enrolled. One hundred and sixty-eight (67.5%) patients were treated with anti-TNF, 37 (14.9%) patients with abatacept, and 44 (17.7%) patients with tocilizumab. After a period of 12-120 months (median 24), 34 (13.6%) patients displayed conversion of at least one screening assay. Out of the 34 patients with conversion, 6 (16.2%) were treated with abatacept, 7 (15.9%) with tocilizumab, and 21 (12.5%) with anti-TNF. During the follow-up period, no patients developed active TB. Our study shows that a proportion of patients (13.6%) converts at least one TB screening assay during biological therapy. This study underscores the American College of Rheumatology advice for annual screening in some or all biologically treated patients.

A fatal case of tuberculous meningitis in a child with juvenile idiopathic arthritis: a diagnostic challenge

“…Although a negative TST or IGRA result cannot eliminate the diagnosis of TB completely, TB screening is important prior to initiating TNF antagonists. Cuomo et al 7 reported that 34 (13.6%) patients whose TB screening tests were negative at baseline displayed conversion of at least 1 screening assay after 12-120 months of treatment with an anti-TNF agent, abatacept, or tocilizumab. On the other hand, conventional tests such as direct examination of CSF, are positive in only 5~20% of cases.…”

Use of biologic agents and risk of tuberculosis in Brazil, a tuberculosis high-burden country

“…According to investigators, these results endorse the ACR recommendation for annual screening in patients treated with biologic agents. 21 …”

Severe bacterial sepsis results in delayed diagnosis of tuberculous lymphadenitis in a rheumatoid arthritis patient treated with adalimumab

“…Although anti-TNF-α treatment is drastically effective in refractory patients with RA, an increased risk of infections often becomes a serious problem (2). Due to the immunological role of TNF-α, the infection caused by anti-TNF-α treatment of the greatest concern is TB; the risk of TB in patients with RA receiving anti-TNF-α treatment has been documented to range from 0.2 to 4% (6). Previous reports estimated extrapulmonary TB to constitute more than 50% of cases of TB in patients treated with anti-TNF-α drugs (4,7,8).…”