Performance of LTBI Screening in Patients with Rheumatic Diseases Using Two Different Interferon-Gamma Releasing Assays.

BACKGROUND: To evaluate the concordance between QuantiFERON-TB Gold in-tube test (QFT-GIT) and T-SPOT.TB test (T-SPOT) for the screening of latent tuberculosis infection (LTBI) in patients with rheumatic diseases (RDs). METHODS: Patients diagnosed as rheumatic diseases (RDs) with clinical indications for test of interferon gamma release test (IGRA) were prospectively recruited from 2019 to 2020. The consistency of QFT-GIT and T-SPOT was assessed by Kappa analysis and the factors associated with the indeterminate results were explored by multivariable logistic analysis. RESULTS: A total of 108 patients with RDs were enrolled, including 64 patients with systemic lupus erythematosus (SLE) and 44 with inflammatory arthritis (26 with rheumatoid arthritis (RA) and 18 with ankylosing spondylitis (AS)). Poor concordance was confirmed between QFT-GIT and T-SPOT results in patients with SLE (K = 0.175, 95% confidence interval [95% CI] [-0.06, 0.40], p < 0.001), whereas concordance was moderate in patients with inflammatory arthritis (K = 0.539, 95% CI [0.11, 0.88], p < 0.001). Among SLE patients, the ratio of indeterminate results in detecting LTBI was significantly higher by QFT-GIT than by T-SPOT (18.8% vs. 4.7%, p = 0.013), while the statistical difference was not achieved in patients with inflammatory arthritis. The multivariable logistic analysis identified that the presence of lower lymphocyte counts (odds ratio [OR] = 0.81, 95% CI [0.68, 0.97], p = 0.020) was the independent predictor of an indeterminate result of the QFT-GIT in SLE patients. CONCLUSIONS: In patients with RDs, the result of screening of LTBI was more definitive by T-SPOT test than QFT, and the concordance was poor especially in the setting of SLE.

A retrospective analysis of first confirmed tubercular lymphadenitis in 129 cases / 中华传染病杂志

Objective@#To analyze and summarize the clinical characteristics of tubercular lymphadenitis, and to improve the ability of diagnosis. @*Methods@#Clinical records of 129 patients first confirmed with tubercular lymphadenitis were collected retrospectively from Nanfang Hospital of Southern Medical University between January 2012 and December 2016. The categorical variables were described with the percentage (%) and compared with the chi-squaue test. Non-normal distribution data were described with M(P25, P75) and compared with rank sum test.@*Results@#The disease courses were different in all cases, mostly of 1-3 months (45.7%). Among the cases, 83 cases (73.6%) complained of lymph node enlargement. The predominant involved lymph node site was cervical (56.6%) with main presentation of single lymph node (61.2%). Only a few cases presented with fever (34.1%). The positive rate of histological examinations was 94.3%, while the positive rate of T cell spot test of tuberculosis infection (T-SPOT.TB) test was 93.3% and purified protein derivative (PPD) test was 69.6%. In the diagnosis of tubercular lymphadenitis, 100 cases (77.5%) were confirmed by histological examinations, 27 cases (20.9%) were given diagnostic treatment, and only 2 case (1.6%) was confirmed by culture. The average period of diagnosis was (10.4±6.5) days. The median age of patients with fever was 50.5 years old with a median disease course of 2.5 months, while the median age of patients fever was 35(24, 49) years old with a median disease course of 1.2(0.5, 6.0) months. The differences between two groups were statistically significant (Z=-3.118 and -2.982, respectively, both P<0.05). Patients with fever had higher proportion of swollen deep lymph nodes (54.5% vs 11.8%), elevated white blood cell counts (34.1% vs 7.1%) and neutrophils (31.8% vs 1.8%), elevated erythrocyte sedimentation rate (97.1% vs 56.1%), elevated C-reactive protein (95.0% vs 40.0%) and received diagnostic treatment (47.7% vs 7.1%) than patients with no fever (χ2=27.337, 15.545, 13.567, 19.347, 25.410 and 28.974, respectively, all P<0.05). @*Conclusions@#Most patients of tubercular lymphadenitis do not present with typical symptoms which might lead to misdiagnose in early stage. The histological examinations and T-SPOT.TB test are especially essential, and histological examinations is the most important diagnostic method. Patients without symptoms of tuberculous poisoning are more common in young people, and the confirmation of diagnosis are mainly based on histological examinations. Patients with symptoms of tuberculous poisoning are more common in middle-aged, with longer duration and deep lymph node involved, which is more serious and nearly half of which are confirmed with diagnostic treatment.

The value of T cell spot test of tuberculosis infection and inflammatory indicators for diagnosis of active tuberculosis in patients with fever of unknown origin / 中华传染病杂志

Objective@#To evaluate the value of T cell spot test of tuberculosis infection(T-SPOT.TB) and inflammatory indicators for diagnosis of active tuberculosis in patients with fever of unknown origin (FUO). @*Methods@#Patients with FUO in Tongji Hospital from Jan 1st 2014 to Feb 28th 2015 were retrospectively enrolled, and general condition, laboratory examination including T-SPOT.TB, blood routine test, procalcitonin (PCT), high sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), lactate dehydrogenase (LDH), serum ferritin (SF) and final diagnosis were collected and analyzed. @*Results@#A total of 395 hospitalized patients with FUO were retrospectively enrolled into this study, among which there were 36 (9.11%) confirmed active tuberculosis (including 7 pulmonary cases and 29 extra-pulmonary cases), 189 (47.85%) bacterial infections, 50 (12.66%) viral infections, 4 (6.32%) fungal infections, 20 (5.06%) neoplastic diseases, 51(12.91%) autoimmune diseases, 25 (6.32%) other diseases. While 20 (5.06%) patients remained un-diagnosed. The sensitivity of T-SPOT.TB for the diagnosis of active TB in patients with FUO was 80.56% (95%CI: 63.43%-91.20%), and the specificity was 83.57% (95%CI: 79.23%-87.16%). The positive predictive value was 32.95% (95%CI: 23.52%-43.89%), and the negative predictive value was 97.72% (95%CI: 95.16%-99.00%). There were significant differences in positive LDH levels (187[141, 255] U/L vs 209[160, 343] U/L) and SF levels (296.2[191.3, 494.8] g/L vs 528.1[281.1, 1 022.0] μg/L) between active tuberculosis group and bacterial infection group (χ2=77.692, H=13.442, H=16.142, all P<0.05). The combination of T-SPOT.TB and multiple inflammatory indicators obtained most valuable efficiency (AUC=0.866) for TB diagnosis. Similarly, there were significant differences in positive ESR (31[15, 78] mm/1 h vs 10[6, 19] mm/1 h), ratio of neutrophil granulocytes ([71.17±12.59]% vs [57.08±20.38]%) between active tuberculosis group and viral infection group (H=32.797, F=6.171, all P<0.05). The combination acquired most valuable efficiency (AUC=0.929). @*Conclusions@#For patients with FUO, T-SPOT.TB combined with inflammatory indicators are valuable for the diagnosis of active tuberculosis.

Role of T?SPOT.TB test in diagnosis of active tuberculosis / 实用医学杂志

Objective To assess the value of T?SPOT.TB test in the diagnosis of active tuberculosis. Methods The clinical data of 975 hospitalized patients receiving T?SPOT.TB test were collected in our hospital. The clinical information and testing results were analyzed. The receiver operating curve (ROC) was used to determine the optimal threshold of T?SPOT.TB test for differentiating active tuberculosis. Results T?SPOT.TB test results showed that the positive rate was 29.26%for the non?active tuberculosis group(n=793),but was 91.21%for active tuberculosis patients group (n = 182),which indicated that the test had a significant value in active tuberculosis detection(P<0.001). The sensitivity of T?SPOT.TB test was 0.912 and the specificity was 0.707. The detection threshold of T?SPOT.TB was optimized. As the spot?forming count(sfc)of ESAT?6 antigen threshold was 11.5 and that of the CEP?10 threshold was 9.5,the efficiency of T?SPOT.TB test for detection of active pulmonary tuberculosis was the highest. Conclusions T?SPOT.TB test has a good diagnostic performance for active tuberculosis, and it can be further optimized to better serve the clinical practice.

Clinical Value of Tuberculosis Infection T Cell ELISPOT and TB Antibody Test in Experimental Tuberculosis of Bones and Joints / 现代检验医学杂志

Objective To analyze and discuss the clinical value of tuberculosis infection T cell ELISPOT test and tuberculosis antibody test used in bone and joint tuberculosis.Methods The patients with suspected bone and joint TB diagnosed and treated in Xishan people's Hospital of Wuxi City from 2012 to 2014 were selected as the objects of this study.They were taken randomly,which divided into T-SPOT.TB test group and tuberculosis antibody test groups.Each group had 162 per-sons.The patients of T-SPOT.TB test group were tested by tuberculosis infection T cell enzyme-linked immunosorbent spot test,tuberculosis antibody test group were taken tuberculosis antibody test,comparative analysis of the sensitivity and speci-ficity of two diagnostic methods were contrastively analyzed.Results The sensitivity and specificity of T-SPOT.TB test group were 93.43% and 84.00%.The sensitivity and specificity of tuberculosis antibody in the experimental group were 40.44% and 53.85%.There was statistical difference between two groups (χ2 =184.62,7.86,all P <0.05).The false posi-tive rate and the false negative rate of T-SPOT.TB test group were 16.00% and 6.57%.The false positive rate and the false negative rate of tuberculosis antibodies in the experimental group were 26.92% and 59.56%,respectively.There was statis-tical difference between two groups (χ2 =7.86,156.18,all P <0.05).In addition,the positive and negative predictive values of T-SPOT.TB test group were 96.97% and 70.00%.Positive and negative predictive values of tuberculosis antibody in the experimental group were 88.71% and 14.74%.There was statistical difference between two groups (χ2 = 20.27,73.06,all P <0.01).Conclusion Compared to experimental tuberculosis antibody,TB infection of T cells ELISPOT test had high sen-sitivity and specificity in the diagnosis of bone and joint tuberculosis.It’s worthy of spreading.

Concordance of the tuberculin skin test and T-SPOT(®).TB test results in kidney transplant candidates.

BACKGROUND: Detection of latent tuberculosis infection (LTBI) in transplant candidates is very important. The tuberculin skin test (TST) and interferon-gamma release assays (IGRAs) are standard immunologic tools for LTBI detection. The aim of this study was to compare the TST results and T-SPOT(®).TB test (a type of IGRAs) in kidney transplant candidates for the screening of LTBI and follow the patients with positive test for an activation of tuberculosis (TB) after transplantation and using anti-TB prophylaxis. MATERIALS AND METHODS: This study was a prospective study and carried out in 44 renal transplant candidates from March 2010 to February 2011 in the teaching hospitals of Isfahan University of Medical Sciences, Iran. TST and T-SPOT(®).TB test were performed and their results evaluated. Patients with a positive skin test and/or T-SPOT(®).TB test were started on anti-TB prophylaxis and followed after transplantation for an activation of their LTBI for 1 year. RESULTS: Overall, 8 (18.2%) patients were positive for TST and 6 (13.6%) patients for T-SPOT(®).TB test. The agreement between TST and T-SPOT(®).TB test was moderate (κ = 0.49, 95% confidence interval 0.145-0.839). The overall agreement between TST and T-SPOT(®).TB test was 86%. No relation was found between the underlying diseases and TST or T-SPOT(®).TB test positivity. Although isoniazid prophylaxis was used for patients with positive TST and/or T-SPOT(®).TB test, one patient had reactivation of TB. CONCLUSION: In kidney transplant candidates both TST and T-SPOT(®).TB test were comparable for the diagnosis of LTBI with reasonable agreement between the tests. However, further studies are needed to determine the ability of T-SPOT(®).TB test to detect LTBI and to evaluate the need for prophylaxis in these patients.