Tuberculosis (TB) is a leading cause of mortality due to infectious disease, but the factors determining disease progression are unclear. Transcriptional signatures associated with type I IFN signalling and neutrophilic inflammation were shown to correlate with disease severity in mouse models of TB. Here we show that similar transcriptional signatures correlate with increased bacterial loads and exacerbate pathology during Mycobacterium tuberculosis infection upon GM-CSF blockade. Loss of GM-CSF signalling or genetic susceptibility to TB (C3HeB/FeJ mice) result in type I IFN-induced neutrophil extracellular trap (NET) formation that promotes bacterial growth and promotes disease severity. Consistently, NETs are present in necrotic lung lesions of TB patients responding poorly to antibiotic therapy, supporting the role of NETs in a late stage of TB pathogenesis. Our findings reveal an important cytokine-based innate immune effector network with a central role in determining the outcome of M. tuberculosis infection.

The TB Portals program is an international consortium of physicians, radiologists, and microbiologists from countries with a heavy burden of drug-resistant tuberculosis working with data scientists and information technology professionals. Together, we have built the TB Portals, a repository of socioeconomic/geographic, clinical, laboratory, radiological, and genomic data from patient cases of drug-resistant tuberculosis backed by shareable, physical samples. Currently, there are 1,299 total cases from five country sites (Azerbaijan, Belarus, Moldova, Georgia, and Romania), 976 (75.1%) of which are multidrug or extensively drug resistant and 38.2%, 51.9%, and 36.3% of which contain X-ray, computed tomography (CT) scan, and genomic data, respectively. The top Mycobacterium tuberculosis lineages represented among collected samples are Beijing, T1, and H3, and single nucleotide polymorphisms (SNPs) that confer resistance to isoniazid, rifampin, ofloxacin, and moxifloxacin occur the most frequently. These data and samples have promoted drug discovery efforts and research into genomics and quantitative image analysis to improve diagnostics while also serving as a valuable resource for researchers and clinical providers. The TB Portals database and associated projects are continually growing, and we invite new partners and collaborations to our initiative. The TB Portals data and their associated analytical and statistical tools are freely available at https://tbportals.niaid.nih.gov/.KEYWORDS tuberculosis, digital health, interactive portals, MDR-TB, Mycobacterium tuberculosis, query, XDR-TB, drug-resistant TB T uberculosis (TB) continues to represent a major health problem worldwide. An estimated one-third of the world's population is living with latent TB (1). In 2015, there were an estimated 10.4 million new (incident) TB cases worldwide, of which 5.9 million (56%) were among men, 3.5 million (34%) were among women, and 1.0 million (10%) were among children. People living with HIV accounted for 1.2 million (11%) of

The global emergence and spread of multidrug resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) has led to the reexamination of surgical therapy as a possible adjunctive therapy for the treatment of drug-resistant TB. We present a case of a 26-year-old HIV-seronegative patient with pulmonary XDR-TB refractory to medical therapy. Surgical resection of the patient’s solitary cavitary lesion was performed as adjunctive treatment and a successful outcome with a combination of surgery and medical therapy was achieved. We review the history of surgical therapy for TB and the literature published on the role of surgical therapy in the treatment of MDR- and XDR-TB. A total of 26 case series and cohort studies were reviewed demonstrating surgical resection is beneficial in the treatment of drug-resistant TB; however, the results may not be applicable to all settings as all studies were observational, tended to select “healthier” TB patients, and all surgeries were performed at specialized thoracic surgery centers. Additional well-designed studies are needed to determine the efficacy of surgery in the treatment of drug-resistant TB.

BackgroundThe country of Georgia has a high prevalence of tuberculosis (TB) and hepatitis C virus (HCV) infection. PurposeTo determine whether HCV co-infection increases the risk of incident drug-induced hepatitis among patients on first-line anti-TB drug therapy.MethodsProspective cohort study; HCV serology was obtained on all study subjects at the time of TB diagnosis; hepatic enzyme tests (serum alanine aminotransferase [ALT] activity) were obtained at baseline and monthly during treatment. ResultsAmong 326 study patients with culture-confirmed TB, 68 (21%) were HCV co-infected, 14 (4.3%) had chronic hepatitis B virus (HBV) infection (hepatitis B virus surface antigen positive [HBsAg+]), and 6 (1.8%) were HIV co-infected. Overall, 19% of TB patients developed mild to moderate incident hepatotoxicity. In multi-variable analysis, HCV co-infection (adjusted Hazards Ratio [aHR]=3.2, 95% CI=1.6-6.5) was found to be an independent risk factor for incident anti-TB drug-induced hepatotoxicity. Survival analysis showed that HCV co-infected patients developed hepatitis more quickly compared to HCV seronegative patients with TB.ConclusionA high prevalence of HCV co-infection was found among patients with TB in Georgia. Drug-induced hepatotoxicity was significantly associated with HCV co-infection but severe drug-induced hepatotoxicity (WHO grade III or IV) was rare.

The pathogenesis of increasing drug resistance among patients with multidrug-resistant or extensively drug-resistant tuberculosis undergoing treatment is poorly understood. Increasing drug resistance found among Mycobacterium tuberculosis recovered from cavitary isolates compared with paired sputum isolates suggests pulmonary cavities may play a role in the development of worsening tuberculosis drug resistance.

Improved knowledge regarding the tissue penetration of antituberculosis drugs may help optimize drug management. Patients with drug-resistant pulmonary tuberculosis undergoing adjunctive surgery were enrolled. Serial serum samples were collected, and microdialysis was performed using ex vivo lung tissue to measure pyrazinamide concentrations. Among 10 patients, the median pyrazinamide dose was 24.7 mg/kg of body weight. Imaging revealed predominant lung lesions as cavitary (n ϭ 6 patients), mass-like (n ϭ 3 patients), or consolidative (n ϭ 1 patient). On histopathology examination, all tissue samples had necrosis; eight had a pH of Յ5.5. Tissue samples from two patients were positive for Mycobacterium tuberculosis by culture (pH 5.5 and 7.2). All 10 patients had maximal serum pyrazinamide concentrations within the recommended range of 20 to 60 g/ml. The median lung tissue free pyrazinamide concentration was 20.96 g/ml. The median tissue-to-serum pyrazinamide concentration ratio was 0.77 (range, 0.54 to 0.93). There was a significant inverse correlation between tissue pyrazinamide concentrations and the amounts of necrosis (R ϭ Ϫ0.66, P ϭ 0.04) and acid-fast bacilli (R ϭ Ϫ0.75, P ϭ 0.01) identified by histopathology. We found good penetration of pyrazinamide into lung tissue among patients with pulmonary tuberculosis with a variety of radiological lesion types. Our tissue pH results revealed that most lesions had a pH conducive to pyrazinamide activity. The tissue penetration of pyrazinamide highlights its importance in both drug-susceptible and drug-resistant antituberculosis treatment regimens.

A better understanding of second-line drug (SLD) pharmacokinetics, including cavitary penetration, may help optimize SLD dosing. Patients with pulmonary multidrug-resistant tuberculosis (MDR-TB) undergoing adjunctive surgery were enrolled in Tbilisi, Georgia. Serum was obtained at 0, 1, 4, and 8 h and at the time of cavitary removal to measure levofloxacin concentrations. After surgery, microdialysis was performed using the ex vivo cavity, and levofloxacin concentrations in the collected dialysate fluid were measured. Noncompartmental analysis was performed, and a cavitary-to-serum levofloxacin concentration ratio was calculated. Twelve patients received levofloxacin for a median of 373 days before surgery (median dose, 11.8 mg/kg). The median levofloxacin concentration in serum (C max ) was 6.5 g/ml, and it was <2 g/ml in 3 (25%) patients. Among 11 patients with complete data, the median cavitary concentration of levofloxacin was 4.36 g/ml (range, 0.46 to 8.82). The median cavitary/ serum levofloxacin ratio was 1.33 (range, 0.63 to 2.36), and 7 patients (64%) had a ratio of >1. There was a significant correlation between serum and cavitary concentrations (r ‫؍‬ 0.71; P ‫؍‬ 0.01). Levofloxacin had excellent penetration into chronic cavitary TB lesions, and there was a good correlation between serum and cavitary concentrations. Optimizing serum concentrations will help ensure optimal cavitary concentrations of levofloxacin, which may enhance treatment outcomes.T he emergence of multidrug-resistant tuberculosis (MDR-TB) remains a major barrier to global TB control (1). The treatment course for MDR-TB (with resistance to isoniazid and rifampin) consists of 18 to 24 months of second-line antituberculosis drugs (SLDs), including a fluoroquinolone and an injectable agent (amikacin, kanamycin, or capreomycin). A 2009 meta-analysis of MDR-TB treatment outcomes found an overall success rate of 62% with a range of 36 to 79% (2). The most recent World Health Organization (WHO) global TB report reported an overall successful outcome rate of 48%, again with a wide range (3). These data show that we are far from the goal of a Ͼ75% successful outcome treatment rate among MDR-TB patients; however, the broad range of successful outcomes suggests that we may be able to more effectively maximize existing SLD regimens. A better knowledge of how to optimize available SLD regimens could improve outcomes and provide important principles for the efficacious use of new drugs.The clinical pharmacology of SLDs has been a neglected area of research (4). Pharmacokinetic studies among patients with drugsusceptible TB demonstrate that low concentrations of first-line drugs are associated with poor clinical outcomes, and simulation studies have found that even with perfect adherence up to 1% of patients would develop further drug resistance during treatment due to variability in drug concentrations (5-7). A recent report on 25 patients with MDR-TB found that plasma SLD concentrations were frequently low and were associated with decreased drug ...

Background New approaches are needed in the treatment of multi- and extensively drug resistant pulmonary tuberculosis (M/XDR-PTB). We evaluated the role of adjunctive surgical therapy in the treatment of M/XDR-PTB in the setting of DOTS-Plus implementation. Methods We conducted an observational cohort study consisting of M/XDR-PTB patients who underwent thoracic surgery at the National Tuberculosis Center in Tbilisi, Georgia between October 2008 and February 2011. Indications for surgery included presence of M/XDR-PTB, localized pulmonary disease, fit to undergo surgery, and either medical treatment failure or such extensive drug-resistance that failure was likely. Second-line anti-tuberculosis medical therapy was administered per WHO recommendations. Results 80 patients (55 MDR, 25 XDR) with PTB underwent adjunctive thoracic surgery. Median age was 30 years and average duration of preoperative M/XDR-PTB medical therapy was 350 days. The following surgical procedures were performed: pneumonectomy (10%), lobectomy (51%), segmentectomy (33%), and thoracoplasty (6%). Mean postoperative follow up time was 372 days. Of 77 patients with evaluable outcomes, 64 (83%) had favorable outcomes including 90% of MDR and 68% of XDR-TB patients. There was no postoperative mortality; postoperative complications occurred in 7 patients (9%). Risk factors for poor treatment outcomes in univariate analysis included cavitary disease, XDR, increasing effective drugs received, positive preoperative sputum culture, and major postoperative surgical complication. Conclusions Patients with M/XDR-PTB undergoing adjunctive thoracic surgery had high rates of favorable outcomes, no surgical related mortality, and low rates of complications. Adjunctive surgery appears to play an important role in the treatment of select patients with M/XDR-PTB.