Reduced neutrophil granular proteins and post-treatment modulation in tuberculous lymphadenitis.

BACKGROUND: Neutrophils are important for host innate immune defense and mediate inflammatory responses. Pulmonary tuberculosis (PTB) is associated with increased neutrophil granular protein (NGP) levels in the circulation. However, the systemic levels of neutrophil granular proteins were not examined in tuberculous lymphadenitis (TBL) disease. METHODS: We measured the systemic levels of NGP (myeloperoxidase [MPO], elastase and proteinase 3 [PRTN3]) in TBL and compared them to latent tuberculosis (LTB) and healthy control (HC) individuals. We also measured the pre-treatment (Pre-T) and post-treatment (Post-T) systemic levels of neutrophil granular proteins in TBL individuals upon anti-tuberculosis treatment (ATT) completion. In addition, we studied the correlation and discriminatory ability of NGPs using receiver operating characteristic (ROC) analysis. RESULTS: Our data suggests that systemic levels of NGPs (MPO, PRTN3, elastase) were significantly reduced in TBL individuals compared to LTB and HC individuals. Similarly, after ATT, the plasma levels of MPO and elastase but not PRTN3 were significantly elevated compared to pre-treatment levels. NGPs (except PRTN3) were positively correlated with absolute neutrophil count of TBL, LTB and HC individuals. Further, NGPs were able to significantly discriminate TBL from LTB and HC individuals. CONCLUSION: Hence, we conclude reduced neutrophil granular protein levels might be associated with disease pathogenesis in TBL.

Altered plasma levels of ßC and γC chain cytokines and post-treatment modulation in tuberculous lymphadenitis.

BACKGROUND: Alterations in ß common (ßC) and γ common (γC) chain cytokines have been described in pulmonary tuberculosis. However, their role in tuberculous lymphadenitis (TBL) disease has not been assessed. METHODS: Thus, in the present study, we have examined the systemic levels of ßC and γC chain cytokines in TBL, latent tuberculosis (LTB) and healthy control (HC) individuals. We have examined the discriminatory potential of both family of cytokines using ROC analysis. Finally, we measured the pre and post-treatment responses of these cytokines after anti-tuberculosis treatment. RESULTS: TBL individuals exhibit significantly increased (IL-3) and diminished systemic levels of (IL-5, GM-CSF) ßC cytokines compared to LTB and HC individuals. TBL individuals also exhibit significantly diminished (IL-2, IL-7) and elevated (IL-4, IL-9) levels of γC cytokines compared to LTB and/or HC. ROC analysis shows a clear discriminatory capacity of both ßC (IL-5) and γC (IL-2) chain cytokines to distinguish TBL from LTB and HCs. The systemic levels of ßC chain cytokines were not significantly altered, but in contrast γC (IL-2 and IL-7) cytokines were significantly modulated after treatment. Finally, no significant correlation was observed for ßC and γC chain cytokines with their respective lymphocyte count of TBL individuals. CONCLUSIONS: Hence, we conclude that altered plasma levels of ßC and γC cytokines are the characteristics of immune alteration in TBL disease and certain cytokines were modulated after treatment.

Diminished Frequencies of Cytotoxic Marker Expressing T- and NK Cells at the Site of Mycobacterium tuberculosis Infection.

Tuberculous lymphadenitis (TBL) individuals exhibit reduced frequencies of CD8+ T cells expressing cytotoxic markers in peripheral blood. However, the frequencies of cytotoxic marker expressing CD4+, CD8+ T cells, and NK cells at the site of infection is not known. Therefore, we measured the baseline and mycobacterial antigen specific frequencies of cytotoxic markers expressing CD4+, CD8+ T cells, and NK cells in the LN (n = 18) and whole blood (n = 10) of TBL individuals. TBL LN is associated with lower frequencies of CD4+ T cells expressing cytotoxic markers (Granzyme B, CD107a) compared to peripheral blood at baseline and in response to PPD, ESAT-6, and CFP-10 antigen stimulation. Similarly, lower frequencies of CD8+ T cells expressing cytotoxic markers (Perforin, Granzyme B, and CD107a) were also present in the TBL LN at baseline and following (except perforin) antigen stimulation. Finally, at baseline and after antigen (PPD, ESAT-6, and CFP-10) stimulation, frequencies of NK cells expressing cytotoxic markers were also significantly lower in TBL LN compared to whole blood. Hence, TBL is characterized by diminished frequencies of cytotoxic marker expressing CD4+, CD8+ T cells, and NK cells at the site of infection, which might reflect the lack of protective immune responses at the site of Mycobacterium tuberculosis infection.

Prevalence of p-glycoprotein (PGP) expression, function and its effect on efficacy of rifampicin in patients with lymph node tuberculosis.

OBJECTIVE: P-glycoprotein (PGP) overexpression may be one of the operating mechanisms of suboptimal responses to antitubercular treatment (ATT) in patients with lymph node tuberculosis. This might become responsible for the development of drug resistance later due to exposure of subtherapeutic concentrations to the mycobacteria. In this study we aim to study the prevalence of PGP expression and function and its relationship with serum concentrations of Rifampicin in consecutive patients with lymph node tuberculosis. METHODS: All newly diagnosed treatment naïve subjects with a confirmed diagnosis of tubercular lymphadenopathy were included in the study and the expression and function of PGP in blood was determined by flowcytometry at baseline and after two months of treatment. Serum levels of Rifampicin was measured at 2 months by high performance liquid chromatography (HPLC). The mean net PGP expression expressed as percent and relative fluorescence indices (RFI) of PGP expression and function respectively was compared at baseline at 2 months and was also correlated with serum rifampicin levels. RESULTS: The mean net PGP expression, RFI of PGP expression and RFI of PGP function were significantly higher in patients with lymph node tuberculosis as compared to healthy controls and the mean net PGP expression and RFI of PGP expression were significantly higher at 2 months as compared to baseline (25.64 ± 5.18% vs. 27.68 ± 4.89%, 4.34 ± 1.09% vs. 4.95 ± 1.55). There was no significant difference in RFI of PGP expression and RFI of PGP function between the poor-responders and responders at baseline and 2 months however there was a trend towards significantly higher net PGP expression amongst poor responders at baseline. The mean serum rifampicin levels were 10.74 ± 2.36 µg/ml in the responder group and 7.86 ± 1.21 µg/ml in the non-responder group and the difference between the two was statistically significant (p = 0.004). CONCLUSIONS: Overexpression of PGP is common in patients with lymph node tuberculosis and leads to lower concentrations of Rifampicin in blood which subsequently may give rise to development of drug resistance. This is also responsible for poor therapeutic responses in these patients. Nonspecific inhibitors of PGP may be used in conjunction with ATT to augment therapeutic response in such cases.

Filarial Coinfection Is Associated With Higher Bacterial Burdens and Altered Plasma Cytokine and Chemokine Responses in Tuberculous Lymphadenitis.

Filarial infections are known to modulate cytokine responses in pulmonary tuberculosis by their propensity to induce Type 2 and regulatory cytokines. However, very little is known about the effect of filarial infections on extra-pulmonary forms of tuberculosis. Thus, we have examined the effect of filarial infections on the plasma levels of various families of (IL-1, IL-12, γC, and regulatory) cytokines and (CC and CXC) chemokines in tuberculous lymphadenitis coinfection. We also measured lymph node culture grades in order to assess the burden of Mycobacterium tuberculosis in the two study groups [Fil+ (n = 67) and Fil- (n = 109)]. Our data reveal that bacterial burden was significantly higher in Fil+ compared to Fil- individuals. Plasma levels of IL-1 family (IL-1α, IL-ß, IL-18) cytokines were significantly lower with the exception of IL-33 in Fil+ compared to Fil- individuals. Similarly, plasma levels of IL-12 family cytokines -IL-12 and IL-23 were significantly reduced, while IL-35 was significantly elevated in Fil+ compared to Fil- individuals. Filarial infection was also associated with diminished levels of IL-2, IL-9 and enhanced levels of IL-4, IL-10, and IL-1Ra. Similarly, the Fil+ individuals were linked to elevated levels of different CC (CCL-1, CCL-2, CCL-3, CCL-11) and CXC (CXCL-2, CXCL-8, CXCL-9, CXCL-11) chemokines. Therefore, we conclude that filarial infections exert powerful bystander effects on tuberculous lymphadenitis, effects including modulation of protective cytokines and chemokines with a direct impact on bacterial burdens.

Altered systemic levels of acute phase proteins in tuberculous lymphadenitis and modulation after treatment.

BACKGROUND: Pulmonary tuberculosis (PTB) is characterized by elevated levels of acute phase proteins (APPs), but their association with tuberculous lymphadenitis (TBL) is poorly studied. METHODS: We examined the systemic levels of APPs (alpha-2-macroglobulin [⍺-2MG], serum amyloid A [SAA], C-reactive protein [CRP] and haptoglobin [Hp]) in TBL, PTB, latent tuberculosis (LTB) and healthy controls (HC) at baseline and in TBL after the completion of anti-tuberculosis treatment (ATT). We have also examined the association of these proteins with lymph node (LN) size, culture grade and multiple versus single LN involvement. RESULTS: TBL individuals exhibited increased systemic levels of ⍺-2MG, SAA, CRP and Hp in comparison to HCs and increased CRP levels in comparison to LTB individuals. TBL individuals also exhibited decreased systemic levels of Hp compared to PTB individuals. APPs were not significantly associated with LN size, LN involvement and culture grade, indicating a lack of association with disease severity. Following ATT, post-treatment levels of ⍺-2MG, CRP and Hp were significantly diminished compared to pre-treatment levels. CONCLUSION: TBL disease is characterized by altered levels of APPs at baseline and modulated following treatment, indicating the presence of systemic inflammation.

Diminished systemic levels of antimicrobial peptides in tuberculous lymphadenitis and their reversal after anti-tuberculosis treatment.

Pulmonary tuberculosis is associated with higher plasma levels of antimicrobial peptides (AMPs) and lower granulysin levels. However, the association of AMPs with tuberculous lymphadenitis (TBL) is not well studied. Hence, we measured the plasma levels of human beta defensin-2 (HBD2), granulysin, human neutrophil peptides 1-3 (HNP1-3) and cathelicidin (LL37) in TBL compared to latent tuberculosis (LTB) and healthy controls (HC) and in TBL individuals upon completion of anti-tuberculosis treatment (ATT). We examined the association of AMPs with TBL lymph node culture grade or lymph node involvement. Finally, the discriminatory potential of these proteins was assessed using receiver operating characteristic (ROC) analysis. TBL individuals display significantly diminished circulating levels of AMPs (granulysin and HNP1-3) but not HBD-2 and LL-37 in comparison to LTB and HCs. Similarly, after ATT, both HBD-2 and HNP1-3 were significantly elevated and LL-37 was significantly reduced in TBL individuals. Granulysin and HNP1-3 discriminates TBL from LTB and HC individuals upon ROC analysis. AMPs did not exhibit significant correlation either with lymph node culture grades or lymph node involvement. Overall, TBL individuals show decreased AMPs and their reversal after ATT suggesting their association with underlying immune alteration in this poorly studied form of TB disease.

Persistent Anemia Combined Increased Serum Sedimentation (ESR) for More Than Two Years Firstly Misdiagnosed as Lymphoma Ultimately Confirmed Systemic Lymph Nodes Tuberculosis by Endobronchial Ultrasound-guided Transbronchial Needle Aspiration Pathology: a Case Report and Literature Review.

BACKGROUND: Anemia combined with increased serum sedimentation (ESR) can be secondary to many diseases and may be ignored when the patient had few clinical symptoms. We report a case of persistent anemia combined with ESR for more than 2 years firstly misdiagnosed as lymphoma. When she received a chest CT scan multiple enlarged lymph nodes were found. METHODS: The chest contrast-enhanced CT scan and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the right hilum enlarged lymph nodes were performed for diagnosis. RESULTS: The chest CT scan and EBUS showed multiple enlarged right hilum and mediastinum lymph nodes without calcification. Pathology of EBUS-TBNA showed multiple granulomas; Zeihl-Neelsen acid-fast stain was positive. CONCLUSIONS: Systemic lymph node tuberculosis is rarely seen in adult patients. In a young patient who has anemia combined with increased ESR should be excluded if those changes are secondary to tuberculosis.

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.

Altered circulating levels of B cell growth factors and their modulation upon anti-tuberculosis treatment in pulmonary tuberculosis and tuberculous lymphadenitis.

B cell activating factor/a proliferation-inducing ligand (BAFF/APRIL) are members of the tumor necrosis factor alpha (TNF) α family of ligands, which are essential for B cell survival, development, and modulation of the immune system. To examine the association of circulating levels of BAFF and APRIL with pulmonary tuberculosis (PTB) and tuberculous lymphadenitis (TBL), we measured the systemic levels of APRIL and BAFF in individuals with PTB, TBL, latent tuberculosis (LTB) and healthy controls (HC). Further, we also examined the pre and post-treatment plasma levels of above-mentioned parameters in PTB and TBL individuals upon completion of anti-TB chemotherapy. Next, the association of these cytokines either with extent of disease, disease severity, bacterial burden in PTB and lymph node culture grade or the lymph node size in TBL was also assessed. Finally, ROC analysis was performed to examine the discrimination capacity of APRIL and BAFF between PTB or TBL with LTB. Our study revealed significantly diminished plasma levels of APRIL in PTB and higher plasma levels of BAFF in both PTB and TBL individuals compared to LTB and HC. Furthermore, we observed a significant increase in APRIL levels in TBL and significantly decreased plasma levels of BAFF in both PTB and TBL after the completion of successful anti-TB treatment. There was no statistically positive relationship between BAFF and APRIL levels and the extent of disease, disease severity and bacterial burden in PTB. In TBL, there was a significant correlation between APRIL (but not BAFF) levels with lymph node culture grades. In contrast, APRIL in PTB and BAFF in TBL were able to clearly discriminate from LTB in ROC analysis. In summary, our results showed altered levels of BAFF/APRIL and their modulation upon chemotherapy, suggesting that these cytokines might be involved in the immune-modulation of TB infection.

The utility of RDW in discrimination of sarcoidosis and tuberculous lymphadenitis diagnosed by ebus.

INTRODUCTION: Erythrocyte distribution width (RDW) is an important indicator of anisocytosis, which is used in the differential diagnosis of anemia and is easily accessible in the complete blood count results. Increased RDW values in coronary artery diseases, pulmonary hypertension and malignancies were detected in the studies. We aimed to demonstrate the usefulness of blood RDW level for the differential diagnosis of granulomatous lymphadenitis associated with tuberculosis and sarcoidosis in our study. MATERIALS AND METHODS: A total of 331 patients, 229 with sarcoidosis (stage I and stage II) and 102 with TB-LA and 50 healthy control group were included in the study. The biopsies were obtained via EBUS-TBNA from 705 lymph nodes of 331 patients. Of tissue diagnosis was non-erosive granulomatous inflammation patients with tuberculosis negative proved by microbiological tests were accepted as sarcoidosis after other causes of granulomatous disease were excluded. RESULT: Of the sarcoidosis patients, 169 (73.7%) were in stage I, and 60 (26.3%) were in stage II. The mean RDW was 14.31 (± 1.6) in the stage I group, 14.99 (± 2.3) in the stage II group, 14.11 (± 2.0) in the TB-LA group, and 13.89 (± 1.3) in the control group. There was a significant difference between the stage II group and the stage I, TB-LA, and control groups (p< 0.05 for all). There was a significant difference in the C-reactive protein levels between the TB-LA and stage I groups (p< 0.01). The eritrocyte sedimentation rate values were higher in the TB-LA group than in both the stage I and stage II groups (p< 0.05). CONCLUSIONS: This is the first study to demonstrate the diagnostic value of RDW in patients with TB-LA and sarcoidosis (Stage I-II) patients diagnosed by EBUS-TBNA. Higher RDW in stage II sarcoidosis than in stage I, TB-LA and control group is related with parenchymal involvement and indicates active inflammation.

Vitamin D3 Status and the Association with Human Cathelicidin Expression in Patients with Different Clinical Forms of Active Tuberculosis.

Low vitamin D (vitD3) is one of the most common nutritional deficiencies in the world known to be associated with numerous medical conditions including infections such as tuberculosis (TB). In this study, vitD3 status and its association with the antimicrobial peptide, human cathelicidin (LL-37), was investigated in Ethiopian patients with different clinical forms of TB. Patients with active TB (n = 77) and non-TB controls (n = 78) were enrolled in Ethiopia, while another group of non-TB controls (n = 62) was from Sweden. Active TB included pulmonary TB (n = 32), pleural TB (n = 20), and lymph node TB (n = 25). Concentrations of 25-hydroxyvitamin D3 (25(OH)D3) were assessed in plasma, while LL-37 mRNA was measured in peripheral blood and in samples obtained from the site of infection. Median 25(OH)D3 plasma levels in active TB patients were similar to Ethiopian non-TB controls (38.5 versus 35.0 nmol/L) and vitD3 deficiency (.

Diminished circulating plasma and elevated lymph node culture supernatant levels of IL-10 family cytokines in tuberculous lymphadenitis.

BACKGROUND: IL-10 family cytokines are associated with the host immune response to pulmonary tuberculosis (PTB), but their association with host response in tuberculous lymphadenitis (TBL) is not known. METHODS: Hence, we examined the circulating levels of the whole panel of IL-10 family cytokines in TBL (n = 44) and compared them to the levels in PTB (n = 44) and healthy control (HC, n = 44) individuals. We also assessed the pre and post-treatment cytokine levels in TBL individuals following the completion of anti-tuberculosis treatment (ATT). Next, we also compared the levels of IL-10 family cytokine in circulation versus lymph node (LN) culture supernatants in a subset of TBL individuals (n = 22). Finally, we also measured the levels of IL-10 family cytokines in tuberculosis antigen (purified protein derivative, PPD) stimulated and unstimulated LN culture supernatants. RESULTS: TBL individuals exhibit significantly decreased levels of IL-10, IL-19, IL-20, IL-24, IL-28B and IL-29 in the circulation when compared to PTB (except IL-10) and HC (except IL-20 and IL-28B) and significantly increased levels of IL-22 when compared to PTB individuals. Following ATT, TBL individuals exhibit significantly elevated levels of IL-10, IL-19, IL-20, IL-24, IL-28B and IL-29 and significantly diminished levels of IL-26. Similarly, TBL individuals also exhibited significantly increased levels of IL-10, IL-19, IL-20, IL-24, IL-28A and IL-29 in LN culture supernatants compared to plasma and significantly decreased levels of IL-22. This was associated with enhanced levels of IL-19, IL-20, IL-24, IL-28B and IL-29 upon PPD stimulation of LN cultures. CONCLUSIONS: Therefore, we demonstrate that TBL is associated with significantly diminished plasma and elevated LN culture supernatant levels of most of the IL-10 family cytokines. This to our knowledge is the first comprehensive examination of IL-10 family cytokines in TBL.

Tuberculous lymphadenitis is associated with altered levels of circulating angiogenic factors.

BACKGROUND: Angiogenic factors are important in granuloma formation and serve as biomarkers in pulmonary tuberculosis (PTB). The relationship between these markers and tuberculous lymphadenitis (TBL) is not known. OBJECTIVE AND DESIGN: To examine the association of vascular endothelial growth factor (VEGF) and angiopoietin (Ang) family molecules in TBL, we measured systemic levels of VEGF-A, C, D, R1 (VEGF-receptor 1), R2, R3, Ang-1, Ang-2 and TIE2 (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) levels in TBL, latent tuberculous infection (LTBI) and lymph node culture supernatants (VEGF-A, C and Ang-2) of the same TBL patients. RESULTS: Circulating levels of VEGF-A and VEGF-C were significantly diminished, whereas VEGF-R2, R3, Ang-2 and TIE2 levels were significantly increased, in TBL. Likewise, VEGF-A, C and Ang-2 levels were significantly increased in lymph node supernatants compared with plasma in individuals with TBL. Receiver operating characteristic curve analysis showed that VEGF-C and VEGF-R2 markers clearly distinguished TBL from LTBI. Following treatment, VEGF-C and Ang-1 levels were significantly altered. No association was observed between angiogenic factors and culture grade or lymph node size, except for VEGF-A. VEGF-A was also significantly decreased in multiple lymph nodes compared with single lymph nodes. CONCLUSIONS: Our data suggest that altered levels of circulating angiogenic factors in TBL might reflect underlying vasculo-endothelial dysfunction. Reversal of angiogenic markers after anti-tuberculosis treatment suggests that these angiogenic markers may serve as biomarkers of disease severity or response to treatment in TBL.

Establishment of Elevated Serum Levels of IL-10, IL-8 and TNF-ß as Potential Peripheral Blood Biomarkers in Tubercular Lymphadenitis: A Prospective Observational Cohort Study.

BACKGROUND: Tubercular lymphadenitis (TL) is the most common form of extra-pulmonary tuberculosis (TB) consisting about 15-20% of all TB cases. The currently available diagnostic modalities for (TL), are invasive and involve a high index of suspicion, having limited accuracy. We hypothesized that TL would have a distinct cytokine signature that would distinguish it from pulmonary TB (PTB), peripheral tubercular lymphadenopathy (LNTB), healthy controls (HC), other lymphadenopathies (LAP) and cancerous LAP. To assess this twelve cytokines (Tumor Necrosis Factor (TNF)-α, Interferon (IFN) -γ, Interleukin (IL)-2, IL-12, IL-18, IL-1ß, IL-10, IL-6, IL-4, IL-1Receptor antagonist (IL-1Ra), IL-8 and TNF-ß, which have a role in pathogenesis of tuberculosis, were tested as potential peripheral blood biomarkers to aid the diagnosis of TL when routine investigations prove to be of limited value. METHODS AND FINDINGS: A prospective observational cohort study carried out during 2010-2013. This was a multi-center study with three participating hospitals in Delhi, India where through random sampling cohorts were established. The subjects were above 15 years of age, HIV-negative with no predisposing ailments to TB (n = 338). The discovery cohort (n = 218) had LNTB (n = 50), PTB (n = 84) and HC (n = 84). The independent validation cohort (n = 120) composed of patients with cancerous LAP (n = 35), other LAP (n = 20) as well as with independent PTB (n = 30), LNTB (n = 15) and HC (n = 20). Eight out of twelve cytokines achieved statistical relevance upon evaluation by pairwise and ROC analysis. Further, variable selection using random forest backward elimination revealed six serum biosignatures including IL-12, IL-4, IL-6, IL-10, IL-8 and TNF-ß as optimal for classifying the LNTB status of an individual. For the sake of clinical applicability we further selected a three analyte panel (IL-8, IL-10 and TNF-ß) which was subjected to multinomial modeling in the independent validation cohort which was randomised into training and test cohorts, achieving an overwhelming 95.9% overall classifying accuracy for correctly classifying LNTB cases with a minimal (7%) misclassification error rate in the test cohort. CONCLUSIONS: In our study, a three analyte serum biosignatures and probability equations were established which can guide the physician in their clinical decision making and step wise management of LNTB patients. This set of biomarkers has the potential to be a valuable adjunct to the diagnosis of TL in cases where AFB positivity and granulomatous findings elude the clinician.

Blood levels of isoniazid in Indian children with tuberculosis.

BACKGROUND: Under the Revised National Tuberculosis Control Program (RNTCP) in India children are receiving antituberculosis treatment (ATT) as per a weight band system. In this children may be receiving antituberculosis drugs in doses which may be more or less than that recommended in mg/kg body weight doses. The recommended dose of isoniazid (INH) for intermittent therapy under the RNTCP is 8-12 mg/kg body weight and by the World Health Organization (WHO) for daily therapy is 10-15 mg/kg body weight. AIMS: To evaluate the blood levels and pharmacokinetics of INH, in children suffering from tuberculosis, at doses administered under the weight band system of the Revised National Tuberculosis Control Program (RNTCP) 2009 of India. DESIGN: Prospective, open label, non-randomized single-dose study conducted in 20 children in the age group 5-12 years attending the outpatient, chest clinic of a tertiary care hospital. RESULTS: Group I (n = 8) included children who received INH in a dose of 10 mg/kg body weight or more and Group II (n = 12) included those who received INH in a dose less than 10 mg/kg body weight. The mean peak INH concentration (Cmax) was 6.03 ± 1.4 µg/mL and this was achieved in 2 hours (Tmax). The mean serum INH concentration was significantly higher in children who received INH in dose more than 10 mg/kg (Group I) as compared to those who received INH in doses lesser than 10 mg/kg body weight (Group II) at all-time points except at 2 hours (P < 0.05). The Cmax was also lower in Group II patients in comparison to Group I patients. Area under the concentration time curve (AUC) was significantly lower in Group II patients (P value 0.002). The elimination half-life of INH was 4.3 ± 0.4 h, elimination rate constant 0.16 ± 0.01/h, the volume of distribution 44.05 ± 5.3 L and clearance 7.1 ± 0.8 L/h. CONCLUSIONS: Lower blood levels and AUC of INH were achieved in children receiving doses of INH lesser than 10 mg/kg body weight. Long elimination half-life of INH is indicative of a slower rate of metabolism. Lower INH levels despite a slower rate of drug metabolism indicate caution with the INH doses being administered to children for intermittent therapy under the RNTCP.

Altered CD8(+) T cell frequency and function in tuberculous lymphadenitis.

CD8(+) T cells secreting Type1 and Type 17 cytokines and cytotoxic molecules play a major role in immunity and protection against pulmonary tuberculosis (PTB), although their role in tuberculous lymphadenitis (TBL) is not well known. To identify the distribution and function of CD8(+) T cells expressing Type1, Type 2 and Type 17 cytokines and cytotoxic molecules in TBL, we examined baseline and mycobacterial-antigen specific immune responses in the whole blood of individuals with PTB and compared them with TBL. TBL is characterized by elevated frequencies of baseline and mycobacterial-antigen stimulated CD8(+) T cells expressing Type 1 (IL-2 and TNFα) and Type 17 (IL-17A and IL-17F) cytokines in comparison to PTB individuals. In contrast, TBL individuals exhibited diminished frequency of CD8(+) T cells expressing perforin, granzyme B and CD107a. The blockade of IL-1R and IL-6R during antigenic stimulation resulted in significantly diminished frequencies of CD8(+) T cells expressing Type 1 and Type 17 cytokines in TBL. Therefore, our data suggest that TBL is characterized by an IL-1 and IL-6 dependent expansion of CD8(+) T cells expressing Type 1 and Type 17 cytokines as well as altered frequencies of cytotoxic molecules, reflecting an important association of these cells with the pathogenesis of TBL.

Whole-blood interferon-gamma release assay for diagnosis of tuberculous lymphadenitis.

Tuberculosis remains a major problem for much of the world. Tuberculous lymphadenitis is the most common type of extrapulmonary tuberculosis, although a difficult invasive procedure is required for its diagnosis. We evaluated the usefulness of the whole-blood interferon-gamma release assay (IGRA) for diagnosis of tuberculous lymphadenitis. From January 2008 to October 2010, 108 patients underwent lymph node biopsy and the IGRA concurrently in Wonju Christian Hospital, Yonsei University Wonju College of Medicine. Among the patients, 27 were diagnosed with tuberculous lymphadenitis and 81 were diagnosed with non-tuberculous lymphadenitis. The diagnostic performances of the IGRA were evaluated. The median patient age was 33 years (interquartile range [IQR] 23.5 to 48 years), and 28 (25.9%) patients were male. No patient was administered immunosuppressive agents such as high-dose steroids or underwent chemotherapy within 90 days before the IGRA test. The IGRA was positive in 25 of 27 patients with tuberculous lymphadenitis and in 13 of 81 patients with non-tuberculous lymphadenopathy. Therefore, the sensitivity of IGRA was 92.6% (95% CI, 82.0 to 100), and the specificity was 80.2% (95% CI, 71.4 to 89.1). In the patients with positive IGRA results, the INF-γ concentration was significantly higher in the patients with tuberculous lymphadenitis compared to that in the patients without tuberculous lymphadenitis (15.58 [IQR 6.87 to 45.10] IU/mL versus 0.97 [IQR 0.65 to 2.41] IU/mL, p < 0.001). In conclusion, the IGRA is helpful for the diagnosis of tuberculous lymphadenitis.

Clinical profile of abdominal tuberculosis in children.

AIM: A retrospective study was conducted in children, suffering from abdominal TB, attending Pediatric TB clinic from 2007 to 2009. MATERIALS AND METHODS: Age-wise distribution and type of abdominal TB were analyzed with clinical features. RESULTS: Out of 285 children with TB, 32 (11.2%) had abdominal tuberculosis. Male: Female ratio was 2.1:1. 7 (21.9%) children were < 5 years of age, 15 (46.9%) children were 5 - 10 years of age, and 10 (31.2%) children were > 10 years of age. The most common clinical features were fever in 24 (75%), pain in abdomen in 17 (53.1%), loss of weight in 15 (46.9%), raised ESR in 14 (43.8%), and loss of appetite in 13 (40.6%) children. TB contact was present in 10 (31.2%), and 7 (21.9%) children had tuberculosis in the past. 28 (87.5%) children had received BCG vaccine, and 17 (53.1%) had a positive Mantoux test. Extra-abdominal tuberculosis was found in 17 patients (53.1%). Duration of fever was more in children less than 5 years of age (127 ± 66 days) than that in children between 5 -10 years (37 ± 30 days) and in > 10 years of age (73 ± 66 days), which is statistically significant (P = 0.0228). Lymph node TB (17 patients, 53.1%) was found to be the commonest, followed by intestinal (10 patients, 31.2%) and peritoneal TB (4 patients, 12.5%). 18 (56.2%) of the total patients had recovered, 7 (21.9%) of all patients failed first line therapy and had to be started on second line drugs, of which 4 (12.5%) were proven to have drug-resistant TB. CONCLUSION: Abdominal TB is seen in 11.2% of children affected with TB, of which over 53% will have extra-abdominal manifestations. Common clinical and laboratory features include fever, pain in abdomen, loss of weight, loss of appetite, and raised ESR. The duration of fever is more in children of younger age group. Lymph node TB is the most common type of abdominal TB. Drug-resistant TB is seen in at least 12.5% of the patients.