Chest Radiograph Screening for Detecting Subclinical Tuberculosis in Asymptomatic Household Contacts, Peru.

The World Health Organization's end TB strategy promotes the use of symptom and chest radiograph screening for tuberculosis (TB) disease. However, asymptomatic early states of TB beyond latent TB infection and active disease can go unrecognized using current screening criteria. We conducted a longitudinal cohort study enrolling household contacts initially free of TB disease and followed them for the occurrence of incident TB over 1 year. Among 1,747 screened contacts, 27 (52%) of the 52 persons in whom TB subsequently developed during follow-up had a baseline abnormal radiograph. Of contacts without TB symptoms, persons with an abnormal radiograph were at higher risk for subsequent TB than persons with an unremarkable radiograph (adjusted hazard ratio 15.62 [95% CI 7.74-31.54]). In young adults, we found a strong linear relationship between radiograph severity and time to TB diagnosis. Our findings suggest chest radiograph screening can extend to detecting early TB states, thereby enabling timely intervention.

Sex-Specific Associations Between Susceptibility to Mycobacterium avium Complex Lung Disease and Programmed Cell Death 1 Gene Polymorphisms.

BACKGROUND: Mycobacterium avium complex lung disease (MAC-LD) preferentially occurs in postmenopausal women and may have immune exhaustion involving the programmed cell death 1 (PD-1) pathway. It is still unknown whether sex-specific associations between susceptibility to MAC-LD and programmed cell death 1 gene (PDCD1) polymorphisms exist. METHODS: Adult patients with MAC-LD (n = 152) and controls (n = 167) were included at 2 medical centers in Taiwan. Five single-nucleotide polymorphisms in PDCD1 genes were genotyped, and their associations with MAC-LD and soluble PD-1 protein were analyzed, especially in sex subgroups. RESULTS: PDCD1 rs2227982 polymorphism was associated with increased risk of MAC-LD in women (adjusted odds ratio for AA vs AG vs GG, 2.205 [95% confidence interval, 1.108-4.389]; P = .02), and the rs10204525 TT genotype was associated with low risk in men (TT vs TC and CC, 0.396 [.176-.890]; P = .02). Compared with men with rs10204525 TT, women with rs2227982 AG and with AA had 2.7- and 5.0-fold increased risks, respectively. Soluble PD-1 levels were lower in the female subgroup with rs2227982 AG and AA than in the remainder (median level [interquartile range], 46.7 [33.7-71.5] pg/mL vs 66.2 [48.6-101.5] pg/mL; P < .001). CONCLUSIONS: PDCD1 genetic polymorphisms were associated with the risk of MAC-LD in a sex-specific pattern, possibly through regulation of PD-1 expression.

Comparative cardiovascular safety of LABA/LAMA FDC versus LABA/ICS FDC in patients with chronic obstructive pulmonary disease: a population-based cohort study with a target trial emulation framework.

BACKGROUND: Use of combinations of long-acting ß2 agonists/long-acting muscarinic antagonists (LABA/LAMA) in patients with chronic obstructive pulmonary disease (COPD) is increasing. Nevertheless, existing evidence on cardiovascular risk associated with LABA/LAMA versus another dual combination, LABA/inhaled corticosteroids (ICS), was limited and discrepant. AIM: The present cohort study aimed to examine comparative cardiovascular safety of LABA/LAMA and LABA/ICS with a target trial emulation framework, focusing on dual fixed-dose combination (FDC) therapies. METHODS: We identified patients with COPD who initiated LABA/LAMA FDC or LABA/ICS FDC from a nationwide Taiwanese database during 2017-2020. The outcome of interest was a hospitalized composite cardiovascular events of acute myocardial infarction, unstable angina, heart failure, cardiac dysrhythmia, and ischemic stroke. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for composite and individual cardiovascular events after matching up to five LABA/LAMA FDC initiators to one LABA/ICS FDC initiator using propensity scores (PS). RESULTS: Among 75,926 PS-matched patients, use of LABA/LAMA FDC did not show a higher cardiovascular risk compared to use of LABA/ICS FDC, with a HR of 0.89 (95% CI, 0.78-1.01) for the composite events, 0.80 (95% CI, 0.61-1.05) for acute myocardial infarction, 1.48 (95% CI, 0.68-3.25) for unstable angina, 1.00 (95% CI, 0.80-1.24) for congestive heart failure, 0.62 (95% CI, 0.37-1.05) for cardiac dysrhythmia, and 0.82 (95% CI, 0.66-1.02) for ischemic stroke. The results did not vary substantially in several pre-specified sensitivity and subgroup analyses. CONCLUSION: Our findings provide important reassurance about comparative cardiovascular safety of LABA/LAMA FDC treatment among patients with COPD.

Disease Progression in Patients With Nontuberculous Mycobacterial Lung Disease of Nodular Bronchiectatic (NB) Pattern: The Roles of Cavitary NB and Soluble Programmed Death Protein-1.

BACKGROUND: In patients with nodular bronchiectatic (NB) nontuberculous mycobacterial lung disease (NTM-LD), risk factors for disease progression have not been clearly investigated. The roles of cavitary NB and soluble programmed death protein-1 (sPD-1), an immune-related biomarker, in the disease course of NB NTM-LD remain unknown. METHODS: Patients with NB NTM-LD were enrolled from 2 medical centers in 2014-2020. We identified cavitary NB, measured sPD-1 levels, and analyzed factors associated with cavitary NB and predictors for disease progression of NB NTM-LD. RESULTS: Of 120 cases of NB NTM-LD, 87 (72.5%) were caused by Mycobacterium avium complex. sPD-1 levels were lower in 13 (10.8%) patients with cavitary NB than in noncavitary patients (P = .020). Over 1.41 ± 1.43 years of follow-up, 12 (92.3%) patients in the cavitary and 66 (61.7%) in the noncavitary group developed disease progression (P = .032). In multivariable analysis, body mass index (BMI [kg/m2]; adjusted hazard ratio [aHR], .895 [95% confidence interval, .811-.988]), sputum smear grade (aHR, 1.247 [1.014-1.534]), cavitary NB (aHR, 2.008 [1.052-3.834]), and sPD-1 (per 10-pg/mL increase; aHR, .889 [.816-.967]) were predictive for disease progression. Notably, sPD-1 showed a dose-dependent association with disease progression (sPD-1 ≤23.5 pg/mL; aHR, 3.306 [1.664-6.567]; sPD-1: 23.6-53.7 pg/mL; aHR, 2.496 [1.390-4.483]) compared with the reference (sPD-1 >53.7 pg/mL). CONCLUSIONS: Patients with NB NTM-LD and low sPD-1, low BMI, high smear grade, and cavitary NB were at high risk for disease progression. sPD-1 was low in patients with cavitary NB phenotype and dose-responsively associated with disease progression.

Using an ATR-FTIR Technique to Detect Pathogens in Patients with Urinary Tract Infections: A Pilot Study.

Urinary tract infections (UTIs) are a leading hospital-acquired infection. Although timely detection of causative pathogens of UTIs is important, rapid and accurate measures assisting UTI diagnosis and bacterial determination are poorly developed. By reading infrared spectra of urine samples, Fourier-transform infrared spectroscopy (FTIR) may help detect urine compounds, but its role in UTI diagnosis remains uncertain. In this pilot study, we proposed a characterization method in attenuated total reflection (ATR)-FTIR spectra to evaluate urine samples and assessed the correlation between ATR-FTIR patterns, UTI diagnosis, and causative pathogens. We enrolled patients with a catheter-associated UTI in a subacute-care unit and non-UTI controls (total n = 18), and used urine culture to confirm the causative pathogens of the UTIs. In the ATR-FTIR analysis, the spectral variation between the UTI group and non-UTI, as well as that between various pathogens, was found in a range of 1800-900 cm-1, referring to the presence of specific constituents of the bacterial cell wall. The results indicated that the relative ratios between different area zones of vibration, as well as multivariate analysis, can be used as a clue to discriminate between UTI and non-UTI, as well as different causative pathogens of UTIs. This warrants a further large-scale study to validate the findings of this pilot research.

PD-L1 Expression in Monocytes Correlates with Bacterial Burden and Treatment Outcomes in Active Pulmonary Tuberculosis.

The PD-1/PD-L1 pathway is critical in T cell biology; however, the role of the PD-1/PD-L1 pathway in clinical characteristics and treatment outcomes in pulmonary tuberculosis (PTB) patients is unclear. We prospectively enrolled PTB, latent TB infection (LTBI), and non-TB, non-LTBI subjects. The expression of PD-1/PD-L1 on peripheral blood mononuclear cells (PBMCs) was measured and correlated with clinical characteristics and treatment outcomes in PTB patients. Immunohistochemistry and immunofluorescence were used to visualize PD-1/PD-L1-expressing cells in lung tissues from PTB patients and from murine with heat-killed MTB (HK-MTB) treatment. A total of 76 PTB, 40 LTBI, and 28 non-TB, non-LTBI subjects were enrolled. The expression of PD-1 on CD4+ T cells and PD-L1 on CD14+ monocytes was significantly higher in PTB cases than non-TB subjects. PTB patients with sputum smear/culture unconversion displayed higher PD-L1 expression on monocytes. PD-L1-expressing macrophages were identified in lung tissue from PTB patients, and co-localized with macrophages in murine lung tissues. Mycobacterium tuberculosis (MTB) whole cell lysate/EsxA stimulation of human and mouse macrophages demonstrated increased PD-L1 expression. In conclusion, increased expression of PD-L1 on monocytes in PTB patients correlated with higher bacterial burden and worse treatment outcomes. The findings suggest the involvement of the PD-1/PD-L1 pathway in MTB-related immune responses.

Depression and recovery of IL-17A secretion in mitogen responses in patients with active tuberculosis-a prospective observational study.

BACKGROUND/PURPOSE: T-helper cell 17 (Th17) is a distinct subset of CD4+ T lymphocytes that is important in the pathogenesis of Mycobacterium tuberculosis infection. This study aims to investigate the characteristics of interleukin (IL)-17A and Th17-related cytokines after stimulation with phytohemagglutinin in patients with active tuberculosis (TB). METHODS: This prospective cohort study enrolled patients with culture-confirmed active TB. QuantiFERON-TB Gold In-Tube (QFT-GIT) assay was performed upon TB diagnosis and at 2 months after TB treatment. Their non-TB-specific secretion of IL-17A and Th17-related cytokines were measured in supernatants of mitogen tubes in QFT-GIT and compared to those of active TB contacts with or without latent TB infection. We analyzed the association between IL-17A secretions and TB presentation and treatment outcomes. RESULTS: A total of 108 patients with TB and 64 non-TB cases were enrolled. The secretion of IL-17A, IL-21, IL-23, and IL-6 were lower in active TB patients upon TB diagnosis. In active TB patients, lower IL-17A secretions were associated with higher grades of sputum smear. In the multivariate analysis, lower IL-17A secretions served as an independent factor associated with 2-month culture non-conversion (odds ratio 23.04, 95% confidence interval [CI] 1.69-84.78) and on-treatment mortality (hazard ratio 28.54, 95% CI 1.30-99.25). The levels of IL-23, and IL-6 significantly increased after 2 months of anti-TB treatment. CONCLUSION: The non-TB-specific IL-17A secretions were lower in active TB patients upon TB diagnosis and associated with higher disease severity and worse treatment outcomes. Trend of recovery of the depressed Th17-related cytokines was noted after effective anti-TB treatment.

Opposite effects of statins on the risk of tuberculosis and herpes zoster in patients with diabetes: A population-based cohort study.

It remains uncertain whether statin use is associated with the risks of tuberculosis (TB) and herpes zoster in patients with type 2 diabetes. This study aims to assess the effects of statins vs nonstatin lipid-lowering agents on the risk of these infectious diseases in patients with diabetes. METHODS: Participants in the Taiwan National Health Insurance Research Database diagnosed with type 2 diabetes in 2001-2013 were classified as statin users, nonstatin users and lipid-lowering drug-free groups. Participants were observed for incident TB and herpes zoster from diabetes diagnosis until treatment crossover or December 2013. Statin user and nonstatin user were the time-dependent variables in Cox regression analysis. RESULTS: Over 240 782 person-years of observation, statin users (n = 17 696) were associated with a lower TB risk than nonstatin users (n = 5327) and the drug-free group (n = 22 316) (adjusted hazard ratio [aHR]: 0.66; 95% confidence interval [CI]: 0.44-0.99 and aHR: 0.57; 95% CI: 0.44-0.73). Compared with nonstatin users, statin users showed a dose-dependent association with TB risk (low-potency statin users, aHR: 0.692; 95% CI: 0.455-1.053; high-potency users, aHR: 0.491; 95% CI: 0.241-0.999). Statin users presented with a higher risk of herpes zoster than nonstatin users and the drug-free group (aHR: 1.23; 95% CI: 1.01-1.50 and aHR: 1.20; 95% CI: 1.09-1.33). The risks of TB and herpes zoster were not statistically different between nonstatin users and the drug-free group. CONCLUSION: Compared with nonstatin drugs, statin use was specifically associated with a decreased risk of TB but a moderately increased risk of herpes zoster in this cohort study.

Treatment for Mycobacterium avium complex lung disease.

Mycobacterium avium complex (MAC) is the major pathologic nontuberculous mycobacteria causing lung disease (LD) in humans worldwide. Although the burden of MAC-LD has increased over the past two decades, treatment remains difficult because of intolerance of long-term antibiotics, lack of adherence to guidelines, and disease recurrence. The current guidelines recommend antibiotic initiation for patients with MAC-LD and severe disease and in those with disease progression. Thus, physicians should consider antibiotic treatment for patients with MAC-LD and cavitary pulmonary lesions or symptomatic non-cavitary nodular bronchiectasis pattern at initial visits and also for those with clinical deterioration during follow-up. The standard three-drug regimen should be macrolide, rifamycin, and ethambutol. Physicians should monitor side effects in patients and maintain the regimen for 12 months, beginning from when sputum conversion has been obtained. With adherence to guideline-based therapy, treatment is successful in two thirds of treatment-naïve patients without macrolide resistance. Without adherence, macrolide resistance can occur, which leads to poor outcomes in patients with MAC-LD. Although the discovery of new treatment options is warranted, adherence to guidelines remains most crucial in treating patients with MAC-LD. It is worth mentioning that the majority of current recommendations are based on observational studies or small-scale clinical trials.

Host immune response against environmental nontuberculous mycobacteria and the risk populations of nontuberculous mycobacterial lung disease.

Nontuberculous mycobacterial lung disease (NTM-LD) prevalence has been increasing over the recent decades. Numerous host factors are associated with NTM-LD development, including susceptible phenotypes such as ciliary defect and lung structural change, pulmonary clearance defect with poor clearance of secretions, and immune suppression. Specifically, regarding the susceptible host phenotypes without clear pathogenesis, a slender body, pectus excavatum, and postmenopausal female status are common. Also, decreased host immunity to NTM, especially T helper 1 cell responses is frequently observed. Even so, the underlying mechanisms remain unclear and relevant large-scale studies are lacking. Infections due to host genetics associated defects are mostly untreatable but rare in Asia, particularly Taiwan. Nevertheless, some risks for NTM-LD are controllable over disease progression. We suggest that clinicians first manage host factors and deal with the controllable characteristics of NTM-LD, followed by optimizing anti-NTM treatment. Further researches focusing on NTM-LD pathogenesis, especially the host-NTM interaction may advance understanding the nature of the disease and develop efficient therapeutic regimens.

Influenza Vaccination and Incident Tuberculosis among Elderly Persons, Taiwan1.

Experimental studies have demonstrated that influenza vaccination may protect against tuberculosis (TB) through a Th17 response. This nationwide cohort study aimed to evaluate the association of influenza vaccination with incident TB among elderly persons in Taiwan. This 2005-2012 study included 99,982 elderly persons (64,290 vaccinated and 35,692 unvaccinated) from the Taiwan National Health Insurance Research Database. During the 738,367 person-years of follow-up, 1,141 (1.14%) persons had incident TB. The cumulative incidences of TB were 145.2 cases/100,000 person-years among vaccinated elderly persons and 175.5 cases/100,000 person-years among unvaccinated elderly persons (p = 0.002). The time-dependent Cox proportional hazards model revealed that influenza vaccination was an independent protective factor for incident TB. Our results suggest that influenza vaccination is associated with a lower risk of incident TB among elderly persons in Taiwan. Further investigation of biologic mechanisms is warranted.

Depressed Gamma Interferon Responses and Treatment Outcomes in Tuberculosis Patients: a Prospective Cohort Study.

Immunosuppression induced by Mycobacterium tuberculosis is important in the pathogenesis of active tuberculosis (TB). However, the impact of depressed TB-specific and non-TB-specific gamma interferon (IFN-γ) response on the treatment outcomes of TB patients remains uncertain. In this prospective cohort study, culture- or pathology-proven active TB patients were enrolled and QuantiFERON-TB Gold In-Tube (QFT-GIT) assays were performed before the initiation of anti-TB treatment. TB-specific IFN-γ responses (TB antigen tube subtracted from the nil tube) and non-TB-specific IFN-γ responses (mitogen tube subtracted from the nil tube) were measured and associated with treatment outcomes, including 2-month culture conversion and on-treatment mortality. A total of 212 active TB patients were included in the analysis. We observed a close correlation between decreased lymphocyte count and lower non-TB-specific IFN-γ responses but not TB-specific IFN-γ responses. Patients with lower non-TB-specific IFN-γ responses had lower 2-month culture conversion rate (71.1% versus 84.7%, respectively; P = 0.033) and higher on-treatment mortality (22.6% versus 5.7%, respectively; P = 0.001) than those with higher non-TB-specific IFN-γ responses. In multivariate analysis, depressed non-TB-specific IFN-γ response was an independent factor associated with 2-month sputum culture nonconversion (odds ratio [OR], 2.49; 95% CI [95% confidence interval], 1.05 to 5.90) and on-treatment mortality (hazard ratio [HR], 2.76; 95% CI, 1.15 to 6.62). In contrast, depressed TB-specific IFN-γ responses were significantly associated with higher on-treatment mortality in univariate analysis but not in multivariate analysis. Our findings suggest that depressed non-TB-specific responses, but not TB-specific IFN-γ responses, as measured by QFT-GIT before the initiation of anti-TB treatment, were significantly associated with worse treatment outcomes in TB patients.

Microbiological Persistence in Patients With Mycobacterium avium Complex Lung Disease: The Predictors and the Impact on Radiographic Progression.

BACKGROUND: Persistent growth of Mycobacterium avium complex (MAC) in the lungs indicates continuous infection in MAC lung disease (MAC-LD), but its clinical significance has not been investigated. We aimed to evaluate the predictors of persistent culture-positivity for MAC (MAC-PP) and its impact on radiographic deterioration in MAC-LD. METHODS: Patients with MAC-LD at multiple medical centers from 2011 to 2016 were enrolled retrospectively. Microbiological persistence of MAC-LD was defined as MAC-PP exceeding 1 year, in contrast with the negative-conversion group. The outcome was radiographic progression, namely, increased number of involved lung areas or cavitary formation. RESULTS: Among 126 patients with MAC-LD, 75 (60%) were in the MAC-PP group; these patients had a higher proportion of radiographic progression (54%) than patients in the negative-conversion group (odds ratio [OR], 3.318; 95% confidence interval, 1.146-9.612). Independent predictors of MAC-PP were low body mass index (BMI), radiographic nodular-bronchiectatic (NB) pattern, and increase in the highest grade of acid-fast bacilli smear (AFS). Patients with BMI <21 kg/m2, NB pattern, and positive AFS had an OR of 17.7 for MAC-PP, and those with ≥2 of the factors had a 4.5-fold increased OR for MAC-PP relative to the comparison group. Other than MAC-PP, the highest AFS grade and no anti-MAC treatment were correlated with radiographic progression. CONCLUSION: Microbiological persistence in patients with MAC-LD is not uncommon and leads to an increased risk of radiographic progression. The predictors of MAC-PP are low BMI, NB pattern, and high AFS grade; if these risk factors are present, anti-MAC treatment should be seriously considered.

Detecting circulating microbial cell-free DNA by next-generation sequencing in patients with Mycobacterium avium complex-lung disease: A pilot study.

Objectives: Determining a diagnosis for non-Tuberculous mycobacterium (NTM)-lung disease (LD) remains difficult. The value of circulating cell-free DNA (cfDNA) secreted from microbes has been established in the detection of pathogens in septic patients. However, it is unknown whether NTM-derived cfDNA is detectable in plasma from patients with NTM-LD and whether this is associated with the disease status of NTM-LD, especially in patients with Mycobacterium avium complex (MAC)-LD. Materials and Methods: In this pilot study, from 2018 to 2019, we enrolled adult patients with MAC-LD at Taipei Veterans General Hospital in Taiwan for the detection of circulating cfDNA. We performed cfDNA extraction from plasma, next-generation sequencing (NGS) for nonhuman cfDNA, and sequence matching to a microbial database and then assessed the association between pathogen cfDNA and MAC-LD. Results: Two (40%) plasma samples from MAC-LD patients had detectable MAC-specific cfDNA, namely one instance of DNA polymerase III alpha subunit and one instance of ATP-binding cassette transporters permease. The plasma samples from the three other MAC-LD cases and the one tuberculosis control were negative for either NTM-derived cfDNA or tuberculosis-related cfDNA. In addition to MAC-specific cfDNA, Ralstonia solanacearum, Staphylococcus aureus, and Pasteurella multocida were the most observed bacteria in our patients. The two patients with MAC-cfDNA positivity yielded higher radiographic scores (P = 0.076) and presented a higher number of nonhuman reads than those without MAC-cfDNA positivity (P = 0.083). Conclusion: Using NGS method, we demonstrated MAC-cfDNA was detectable in patients with MAC-LD. Further large-scale research is warranted to assess the clinical value of detecting MAC-specific cfDNA in MAC-LD patients.

Prescription Patterns of New Use of Fixed-Dose Combination Inhalers in Patients with Chronic Obstructive Pulmonary Disease: Long-Acting ß2 Agonists Plus Long-Acting Muscarinic Antagonists versus Long-Acting ß2 Agonists Plus Inhaled Corticosteroids.

Background: The clinical guideline recommends use of long-acting ß2 agonists/long-acting muscarinic antagonists (LABA/LAMA) or long-acting ß2 agonists/inhaled corticosteroids (LABA/ICS) combination therapies for patients with severe chronic obstructive pulmonary disease (COPD). The fixed-dose combination (FDC) inhalers of LABA/LAMA and LABA/ICS were reimbursed in Taiwan in 2015 and in 2002, respectively. This study aimed to examine prescription patterns of new use of either FDC therapy in real-world practice. Methods: We identified COPD patients who initiated LABA/LAMA FDC or LABA/ICS FDC between 2015 and 2018 from a population-based Taiwanese database with 2 million, randomly sampled beneficiaries enrolled in a single-payer health insurance system. We compared number of LABA/LAMA FDC and LABA/ICS FDC initiators in each calendar year, from different hospital accreditation levels, and cared for by different physician specialties. We also compared baseline patient characteristics between LABA/LAMA FDC and LABA/ICS FDC initiators. Results: A total of 12,455 COPD patients who initiated LABA/LAMA FDC (n=4019) or LABA/ICS FDC (n=8436) were included. Number of LABA/LAMA FDC initiators increased apparently (n=336 in 2015 versus n=1436 in 2018), but number of LABA/ICS FDC initiators decreased obviously (n=2416 in 2015 versus n=1793 in 2018) over time. The preference of use of LABA/LAMA FDC varied across clinical environments. The proportions of LABA/LAMA FDC initiators were more than 30% in the setting of non-primary care clinics (eg, medical centers) and in the services of chest physicians; but were only less than 10% in primary care clinics and non-chest physicians' services (eg, family medicine physicians). LABA/LAMA FDC initiators appeared to be older, male, to have more comorbidities, and to utilize resources more frequently compared to LABA/ICS FDC initiators. Conclusion: This real-world study found evident temporal trends, variations in healthcare provider, and differences in patient characteristics among COPD patients who initiated LABA/LAMA FDC or LABA/ICS FDC.

Role of nebulized colistin as a substitutive strategy against nosocomial pneumonia caused by CR-GNB in intensive care units: a retrospective cohort study.

BACKGROUND: Adverse reactions, especially nephrotoxicity, are great concerns of intravenous colistin treatment. The role of substitutive nebulized colistin in treating nosocomial pneumonia caused by carbapenem-resistant Gram-negative bacterial (CR-GNB) in critically ill patients remains unknown. METHODS: This retrospective study enrolled patients with nosocomial pneumonia caused by colistin-susceptible CRGNB in the intensive care unit (ICU) without intravenous colistin treatment. Patients were categorized based on whether substitutive nebulized colistin was used alongside other intravenous antibiotics. Clinical responses and mortality rates were compared between the two groups in the original and propensity score (PS)-matched cohorts. This study aimed to investigate the clinical effectiveness of substitutive nebulized colistin in treatment outcomes of nosocomial pneumonia caused by CR-GNB. The impact of dosing strategy of nebulized colistin was also explored. RESULTS: In total, 343 and 214 patients with and without substitutive nebulized colistin, respectively, were enrolled for analysis. In the PS-matched cohort, clinical failure rates on day 7 (22.6 vs. 42.6%, p = 0.001), day 14 (27.0 vs. 42.6%, p = 0.013), and day 28 (27.8 vs. 41.7%, p = 0.027) were significantly lower in patients with nebulized colistin. In multivariate analysis, nebulized colistin was an independent factor associated with lower day 14 clinical failure (Original cohort: adjusted odds ratio (aOR) 0.45, 95% confidence interval (CI) 0.30-0.67; PS-matched cohort: aOR 0.48, 95% CI 0.27-0.87). There were no differences in clinical failure rate and mortality rate between patients receiving high (> 6 MIU/day) and low (≤ 6 MIU/day) dose nebulized colistin in the PS-matched cohort. CONCLUSIONS: In ICU-admitted patients with nosocomial pneumonia caused by colistin-susceptible CRGNB, substitutive nebulized colistin was associated with better clinical outcomes.

Predicting stringent QuantiFERON-TB Gold Plus conversions in contacts of tuberculosis patients.

OBJECTIVES: To assess associations between disease severity in index TB patients and QuantiFERON-TB Gold Plus (QFT-Plus) results in contacts, and predictors for QFT-Plus conversion in contacts over 6-12 months. METHODS: TB patients (n = 295) and the contacts (n = 1051) were enrolled during 2018-2021 with QFT-Plus performed at baseline and months 6 and 12. A strong CD8 response was defined as TB2 interferon gamma (IFN-γ) response minus TB1 >0.6 IU/ml and stringent conversion as change from QFT-plus negative to high-positive QFT-Plus (TB1 or TB2 IFN-γ responses >0.7 IU/ml). RESULTS: Contacts with index TB patients with sputum smear >1+ was associated with positive QFT-Plus compared to those without (p < 0.001). Contacts with index TB patients with bilateral lung disease were more likely to have strong CD8 responses than those without (p = 0.038). QFT-Plus stringent conversion occurred in 9.7% of contacts over 6-12 months. A TB1 IFN-γ response ≥0.03 IU/ml combined with a TB2 ≥0.06 IU/ml was predictive of a 19-fold increased risk for QFT-Plus stringent conversion in contacts (odd ratio 19.565 [8.484-45.116], p < 0.001). CONCLUSION: Bacterial burden and bilateral lung disease of index TB patients were associated with positive QFT-Plus and strong CD8 responses in contacts. TB1 and TB2 IFN-γ responses were synergistically predictive of stringent conversion in contacts.

The Impact of Nontuberculous Mycobacteria Species on Mortality in Patients With Nontuberculous Mycobacterial Lung Disease.

Patients with nontuberculous mycobacterial lung disease (NTM-LD) have increased mortality. The impact of NTM species on the risk of mortality remains unclear, especially that of death by non-cancer causes. We conducted a retrospective cohort study from 2006 to 2018 in a tertiary-care hospital in Taiwan. We enrolled patients who fulfilled the microbiological diagnostic criteria of NTM-LD. The mortality causes within 8 years after diagnosis were identified, and the Cox proportional hazard regression was performed for risk factors of mortality. A total of 1,652 subjects with NTM-LD were included. Among them, 723 (43.8%) were infected by Mycobacterium avium complex (MAC), 408 (24.7%) by M. abscessus complex (MABC), 120 (7.3%) by Mycobacterium kansasii (MK), 304 (18.4%) by other rapid-growing mycobacteria (RGM), and 97 (5.9%) by other slow-growing mycobacteria (SGM) groups. The 8-year all-cause mortality was 45.2% for all and the highest in the MK-LD group (59.2%), followed by the MABC-LD and MAC-LD groups. The adjusted hazard ratios were 2.20 (95% confidence interval: 1.40-3.46) in the MK-LD, 1.85 (1.54-2.22) in the MABC-LD, and 1.65 (1.12-2.41) in the MAC-LD groups for all-cause mortality, compared with the SGM group. Kaplan-Meier survival curves showed that all-cause mortality, non-cancer mortality, and mortality due to chronic airway diseases were significantly correlated with NTM species (log-rank p = 0.0031, < 0.001, and 0.001, respectively). High 8-year mortality rates were found in patients with NTM-LDs according to different NTM species. Notably, the difference was significant in non-cancer mortality causes, especially in chronic airway diseases.