Diagnostic Utility of Interferon-Gamma Release Assay in Tuberculous Lymphadenitis.

Objective The aim of this study was to evaluate the diagnostic performance of T-SPOT.TB for tuberculous lymphadenitis. Methods Suspected tuberculous lymphadenitis patients between September 2010 and September 2018 who had both peripheral blood T-SPOT.TB test and lymph node biopsy were retrospectively enrolled in this study. The cutoff value of T-SPOT.TB test for peripheral blood was set as 24 spot forming cell (SFC)/10 6 periphreral blood monocyte cell (PBMC) according to the instruction of testing kits. The gold standard for diagnosis of TBL was the combination of microbiology results, histopathology results and patient's response to anti-TB treatment. Diagnostic efficacy of T-SPOT.TB was evaluated, including sensitivity, specificity, accuracy, predictive values, and likelihood ratio. Results Among 91 patients who met the inclusion criteria, we excluded 8 cases with incomplete clinical information and 6 cases who lost to follow-up. According to the gold standard, there were 37 cases of true TBL (9 confirmed TBL and 28 probable TBL), 30 cases of non-TBL, and 10 cases of clinically indeterminate diagnosis who were excluded from the final analyses. The T-SPOT.TB tests yielded 43 cases of positive response and 24 cases of negative response. The sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR) and negative likelihood ratio (NLR) of peripheral blood T-SPOT.TB for diagnosing TBL were 89.2%, 66.7%, 79.1%, 76.7%, 83.3%, 2.68 and 0.16, respectively. The number of SFCs of T-SPOT.TB in TBL patients [432(134-1264)/10 6 PBMCs] was higher than that in non-TBL patients [0 (0-30) /10 6PBMCs] with a significant difference (Z=-5.306, P <0.001).Conclusion T-SPOT.TB is a rapid and simple diagnostic test for TBL with a high sensitivity and negative predictive value.

Clinical and Laboratory Characteristics of Patients with Nontuberculous Mycobacterium Bloodstream Infection in a Tertiary Referral Hospital in Beijing, China.

BACKGROUND: Nontuberculous Mycobacterium (NTM) bloodstream infection (BSI) is relatively rare. We aimed in this study to evaluate the clinical characteristics, laboratory evaluation, and outcomes of patients with NTM BSI. METHODS: We retrospectively reviewed the clinical records of inpatients with NTM BSI at our institution between January 2008 and January 2015 and recorded clinical parameters including age, gender, underlying disease, clinical manifestation, organs involved with NTM disease, species of NTM, laboratory data, treatment and outcome of these patients. We also reviewed the reported cases and case series of NTM BSI by searching PubMed, EMBASE, and Wanfang databases. Data of normal distribution were expressed by mean ± standard deviation (SD). Data of nonnormal distribution were expressed by median and interquartile range (IQR). RESULTS: Among the ten patients with NTM BSI, the median age was 51 years (IQR 29-57 years) and three patients were males. Eight patients were immunocompromised, with underlying diseases including human immunodeficiency virus (HIV) infection (one patient), rheumatic diseases (two patients), breast cancer (one patient), myelodysplastic syndrome (two patients), and aplastic anemia (two patients). Other organ(s) involved were lung (two patients), endocardium (two patients), brain, spinal cord, and soft tissue (one each patient). The median lymphocyte was 0.66 × 109/L (IQR 0.24-1.93 × 109/L). The median cluster of differentiation 4 (CD4) cell count was 179/mm3 (IQR 82-619/mm3). Five patients died (three with hematological diseases, one with breast cancer, and one with rheumatic disease), three recovered, and two were lost to follow-up. CONCLUSIONS: We reported all cases in our hospital diagnosed with bloodstream NTM infection that was rarely reported. In this group of patients, patients usually had a high fever and could have multiple organ involvements. All patients with poor prognosis had underlying diseases.

Clinical and Laboratory Diagnosis of Intestinal Tuberculosis.

BACKGROUND: Tuberculosis (TB) remains a worldwide problem. Intestinal TB (ITB) constitutes a major public health problem in developing countries and has been associated with significant morbidity and mortality. The aim of this study was to characterize the clinical, radiological, endoscopic, and pathological features of ITB and to define the strategy for establishing the diagnosis. METHODS: A retrospective study (from January 2000 to June 2015) was carried out in Peking Union Medical College Hospital and all hospitalized cases were diagnosed as ITB during the study period were included. The relevant clinical information, laboratory results, microbiological, and radiological investigations were recorded. RESULTS: Of the 85 cases, 61 cases (71.8%) were ranged from 20 to 50 years. The ileocecal region was involved in about 83.5% (71/85) of patients. About 41.2% (35/85) of patients had co-existing extra ITB, especially active pulmonary TB. Abdominal pain (82.4%) was the most common presenting symptom followed by weight loss (72.9%) and fever (64.7%). Both T-cell spot of TB test (T-SPOT.TB) and purified protein derivatives (PPD) tests were performed in 26 patients: 20 (76.9%) positive T-SPOT.TB and 13 (50.0%) positive PPD were detected, with a statistical significant difference (P = 0.046). Twenty cases (23.5%) were histopathology and/or pathogen confirmed TB; 27 cases (31.8%) were diagnosed by clinical manifestation consistent with ITB and evidence of active extra ITB; 38 cases (44.7%) were diagnosed by good response to diagnostic anti-TB therapy. CONCLUSIONS: ITB is difficult to diagnose even with modern medical techniques due to its nonspecific clinical and laboratory features. At present, combination of clinical, endoscopic, radiological, and pathological features continues to be the key to the diagnosis of ITB.

Diagnostic Value of T-cell Interferon-γ Release Assays on Synovial Fluid for Articular Tuberculosis: A Pilot Study.

BACKGROUND: Tuberculosis (TB) remains a major global public health challenge. Articular TB is an important form of extrapulmonary tuberculosis, and its diagnosis is difficult because of the low sensitivity of traditional methods. The aim of this study was to analyze the diagnostic value of T-SPOT.TB on synovial fluid for the diagnosis of articular TB. METHODS: Patients with suspected articular TB were enrolled consecutively between August 2011 and December 2015. T-SPOT.TB was performed on both synovial fluid mononuclear cells (SFMCs) and peripheral blood mononuclear cells (PBMCs). The final diagnosis of articular TB was independent of the T-SPOT.TB result. The diagnostic sensitivity, specificity, predictive value, and likelihood ratio of T-SPOT.TB on SFMCs and PBMCs were analyzed. RESULTS: Twenty patients with suspected articular TB were enrolled. Six were diagnosed with articular TB, and 14 patients were diagnosed with other diseases. Sensitivity and specificity were 83% and 86% for T-SPOT.TB on SFMCs, and 67% and 69% for T-SPOT.TB on PBMCs, respectively. The positive predictive value (PPV) and negative predictive value (NPV) of T-SPOT.TB on SFMCs were 71% and 92%, respectively. The PPV and NPV were 50% and 82% for T-SPOT.TB on PBMCs. CONCLUSION: Sensitivity, specificity, and NPV of T-SPOT.TB on SFMCs appeared higher than that on PBMCs, indicating that T-SPOT.TB on SFMCs might be a rapid and accurate diagnostic test for articular TB.