Immunosuppression Adversely Affects TST but Not IGRAs in Patients with Psoriasis or Inflammatory Musculoskeletal Diseases

Abstract

The performance of the interferon gamma release assays (IGRAs) and tuberculin skin test (TST) was reviewed retrospectively in patients with psoriasis, inflammatory musculoskeletal diseases, or miscellaneous inflammatory conditions. The study was carried out over a 22-month period using 109 records of patients with psoriasis (n = 21), musculoskeletal disease (n = 74), or other inflammatory conditions (n = 14). Forty-four (48%) of 109 patients were on immunosuppressive therapy and 38/109 (35%) on systemic glucocorticoid therapy. The agreement between the IGRAs was substantial (κ = 0.71) whilst that between the IGRAs and TST was low (κ = 0.32). Logistic regression models revealed that IGRAs associated with risk factors for latent tuberculosis infection better than TST. TST was influenced by age, BCG vaccination, sex, and glucocorticoid therapy. We found that IGRAs performed equally well with low level of indeterminate results (1-2%). IGRAs were superior to TST because the latter was influenced by BCG-vaccination status and immunosuppressive therapy.

Interferon-γ release assay for tuberculosis in patients with psoriasis treated with tumour necrosis factor antagonists:in vivoandin vitroanalysis

“…The lack of a gold‐standard method for LTBI diagnosis requires careful clinical management, including not only TST, but also evidence of a history of untreated or partially treated TB, exposure to cases of active TB, presence of residual abnormalities on chest radiograph indicative of prior TB infection, and residence in endemic areas. Recently, new data have emerged regarding the clinical use of IGRA for LTBI screening in patients with psoriasis requiring anti‐TNF therapy . Differently from TSTs, IGRAs may be repeated any number of times with no risk of boosting or sensitization, and this supports their usefulness, when serially applied, in monitoring TB infection during long‐term systemic treatment with anti‐TNF agents.…”

“…Recently, new data have emerged on the clinical use of the interferon‐γ release assay (IGRA) for detection of LTBI in patients with psoriasis requiring anti‐TNF therapy, but prospective studies on the monitoring of TB reactivation in this risk group are scarce …”

“…8 Novel screening tools, which measure the release of interferon (IFN)-c following stimulation of T cells with Mycobacterium tuberculosis antigens, have been introduced for diagnosis of LTBI and show superior diagnostic accuracy in comparison with TST. 9,10 Recently, new data have emerged on the clinical use of the interferon-c release assay (IGRA) for detection of LTBI in patients with psoriasis requiring anti-TNF therapy, [11][12][13][14][15][16] but prospective studies on the monitoring of TB reactivation in this risk group are scarce. 13,16 The aim of this study was to investigate the performance of serial QuantiFERON-TB Gold In-Tube (QFT-GIT; Cellestis), one of the commercially available IGRA tests, in LTBI screening and monitoring of patients with psoriasis undergoing anti-TNF treatment.…”

Challenges in screening for latent tuberculosis in inflammatory bowel disease prior to biologic treatment: a UK cohort study

“…TST can be falsely negative in immunosuppressed patients17; therefore, we may have underestimated the overall prevalence of LTBI. In practice, patients who come from a high TB prevalence country are considered for LTBI prophylaxis regardless of their TST or IGRA result.…”

Nodular scleritis and granulomatous polyangiitis (Wegener) mimicking tuberculosis

“…As widely reported in the literature, immunosuppressed patients can have a negative PPD test even in the presence of active pulmonary tuberculosis, e.g. when prednisone is used [19][20][21] . Recent international studies suggest that even if the PPD test is normal, pulmonary tuberculosis should be diagnosed and treated in symptomatic elderly patients or when imaging studies are altered [22][23][24][25] .…”