Use of Quantiferon-TB-Gold in Tube(®) test for detecting latent tuberculosis in patients considered as candidates for anti-TNF therapy in routine clinical practice.

BACKGROUND/METHODS: Quantiferon-TB-Gold in Tube(®) test (QFT-G-IT) may have advantages if combined with TST when screening for Latent Tuberculosis Infection (LTBI) prior to initiating anti-TNF therapy in an area of intermediate tuberculosis incidence such as Spain. In a small-scale prospective study, we evaluate the use of QFT-G-IT in combination with the screening recommended in Spain (Tuberculin-Skin Test, TST retest, clinical data, and Chest X-Ray (CXR)) for LTBI in patients considered as candidates for anti-TNFα treatment. RESULTS: From June 2008 to October 2010, 123 patients from a 300-bed hospital in Palma de Mallorca (Spain) were included in the study. The majority of patients were under immunosuppressive therapy. A positive TST and TST booster were found in 22 and 17 patients, respectively. Thus 39 (31.7%) of the 123 patients had a positive TST. QFT-G-IT was positive in 16 patients (13.6%), indeterminate in 4 (3.2%), and negative in 103 (83.7%). One of the two tests was positive and LTBI was diagnosed in 34.1% of patients. The agreement between TST and QFT-G-IT among vaccinated patients was low and not statistically significant (Kappa=0.15) and was almost perfect among non-BCG vaccinated patients (K=0.81). TST positive responses were significantly related to BCG-vaccination (p<0.05) and QFT-G-IT positive response rates were related to older age (p<0.05). CONCLUSION: QFT-G-IT may have advantages when combined with TST in immunosuppressed patients especially in older patients with a negative TST; in BCG vaccinated patients with a positive TST, QFT-G-IT could avoid unnecessary treatments and toxicities related to a false-positive TST result.

Experience of a monographic tuberculosis unit: the first 500 cases.

INTRODUCTION: Tuberculosis (TB) remains a highly prevalent and potentially severe disease. However, since 2002 the annual incidence has been decreasing both worldwide and in Spain, where the incidence varies widely between regions. The main objective of this study is to describe the experience of a monographic TB unit in a second level hospital. PATIENTS AND METHODS: A descriptive study was carried out which included all cases of TB diagnosed in a monographic unit of a secondary hospital between 2003 and 2011. Demographic, clinical, epidemiological and microbiological data were recorded. RESULTS: We analyzed 500 TB cases and found an increasing annual incidence in all subgroups, including native and immigrant populations. Most cases (63.8%) were male, with a median age of 36 years (range 8 months-90 years). In total, 39.8% of patients were foreign born. Coinfection with human immunodeficiency virus was found in 11% of cases. The pulmonary form was most frequently diagnosed (63.8%). Overall mortality was 5.8% with no significant differences between groups (including foreign born and human immunodeficiency virus positive patients). CONCLUSIONS: Although TB incidence is globally decreasing, in our study we found an increasing number of cases in recent years in all subgroups, which can be explained by this being a monographic unit with an intensive contact tracing program.